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Sedbergh
26th Jul 2006, 11:53
Hi all

The CAA "consultation" period on the compulsory fitting of Mode S to all flying machines in 2008 ends on 29th August.

There are comments on the PFA and BGA websites on the subject, also a long document on

www.caa.co.uk/dapconsultations

Which seeks to justify the proposal. Also a response questionnaire which I think we ALL should fill in (no matter which side of the spectrum you fall on)

PS personally I think this should be a sticky until end of August, it's important

gpn01
3rd Aug 2006, 22:58
Has everybody filled in their response to the CAA's proposal about amending The Air Navigation Order 2005 "For The Purpose Of Improving The Technical Interoperability Of All Aircraft In UK Airspace"....which translates into mandatory fitting of Mode-S transponders to ALL aircraft ?

I'd urge anybody who flies light aircraft, helicopters, gliders, hang gliders, paragliders, microlights, balloons, etc. to respond before the CAA removes all open airspace in the UK. The PFA and BGA have both published arguments against the proposal:

PFA: http://www.pfa.org.uk/mode_s.asp
BGA: http://www.gliding.co.uk/bgainfo/airspace/transponders.htm

Not sure if the BHPA and BMAA have produced a response yet (as this proposal could affect them as well).

The CAA proposal is available at:

http://www.caa.co.uk/default.aspx?categoryid=7&pagetype=90&pageid=6476

This includes an online facility to respond. Replies are needed by 29th August.

Imagine the future - you'll need an approved, servicible Mode-S transponder before you'll be allowed to fly any civilian light aircraft in UK airspace (both controlled and 'uncontrolled').

Sedbergh
4th Aug 2006, 07:12
And don't forget it'll probably cost you at least 2 grand to fit, and £200 a year to run, irrespective of hours flown - even in gliders/microlights worth a total of 2 grand!

The parallels with the government ID card scheme are fascinating - unknown technology (well for battery powered Mode S), very dubious benefits (if any) and undefined but rapidly rising costs - but the hapless taxpayer (GA pilots in this case) will pick up the tab

- oh and total "gold plating" compared with anything Europe may propose. :{

Try writing to your MP and draw his attention to the similarities (unless your MP is named T Blair of course (or you work for an avionica manufacturer)

IO540
4th Aug 2006, 07:22
£200 a year to run

Do you have a reference for the above?

Sedbergh
4th Aug 2006, 07:50
See Page 28 of the CAA Regulatory Impact Document

Annual check £80 to £140
Biennial check £45 - £67.50 (Don't forget the 50 pence!)
Annual licence £20


So the CAA's low end estimate for annual operation is £122.50
Their high end estimate is £193.75

Do you ever recall a government estimate for electronic equipment that didn't finally cost at least double (cf any military equipment, passports and identity cards!):{

So based on the CAA's "estimates" I reckon £200 annually will be optimistic

pistongone
5th Aug 2006, 11:33
I dont have exact figures available unfortunately, maybe one of you knows where to find them? for the number of mid air collisions in uncontrolled airspace, over the last ten years:confused: . I can only remember a few. So if you consider the cost of upgrading the entire GA fleet to include gliders ballons etc, to stop what is virtually a non-problem, you must come to the conclusion that the benefit DOES NOT WARRANT THE COST, a consideration the FAA has to bear very much in such situations. If you look deeper into the information provided by :cool: euro-CON-trol:cool: , it would appear the main reason for implementing mode s is to get more commercial traffic into european airspace and increase revenues for the airlines and governments via tax reciepts. Guess who is paying for this? US:= !! The airlines moan that they were subsiding us with regards to the CAA funding, well i think we will be subsidising them to a much higher degree with this mode s con of the century!! Also notice that Spain and Italy, two of the more bureaucratic European union menbers, are not implementing mode s at this time even though the object of the exercise it to improve the SAFETY in the core euro area. Come to think of it, the only time i can remember commercial traffic hitting each other in european airspace is on the ground in fog. This whole thing stinks of european-un-elected-beaurocrats pushing through proposals for an objective that is not entirely clear, and maybe some pockets of said beaurocrats will be substancially heavier after the succesfull fleecing of the GA population! I am off to the pub to cool down now! Cheers:ugh: :ugh:

NorthSouth
5th Aug 2006, 17:11
Can anyone refute any of the following?

1. The new NATS En Route Raytheon radars (which have Mode S SSR) remain capable of detecting Mode A/C transponders

2. There are currently no terminal/approach radar systems in the UK (except Heathrow?) which have Mode S, so making Mode S mandatory in terminal and uncontrolled airspace is pointless until all those units have bought new radars or junked their SSRs and bought a feed from NATS instead.

3. Current approved ACAS systems in airliners etc can detect Mode A/C transponders just as well as Mode S transponders.

If my assumptions are correct there seems to me to be no case for requiring aircraft which have a perfectly serviceable Mode C transponder to bin it and buy a new Mode S one.

NS

robin
6th Aug 2006, 07:30
So if you consider the cost of upgrading the entire GA fleet to include gliders ballons etc, to stop what is virtually a non-problem, you must come to the conclusion that the benefit DOES NOT WARRANT THE COST, :

You might say that but actually the CAA are counting the value of a life as being £1.4m. So they would deny your view

bookworm
6th Aug 2006, 08:00
If my assumptions are correct there seems to me to be no case for requiring aircraft which have a perfectly serviceable Mode C transponder to bin it and buy a new Mode S one.

I agree. On a point of detail, it's Terminal Control rather than Heathrow, I think, that has Mode S user-interface capability, but even there the downlink parameters of ELS are not used (i.e. they can't display your registration, even though you're sending it to them).

The argument for requiring Mode S for airways flights was stronger, even though the analysis was flawed, because of the need to track aircraft in high traffic density areas and the shortage of Mode A codes. But the case for throwing out a perfectly good Mode A/C transponder and replacing it with Mode S is paper-thin.

IO540
6th Aug 2006, 08:46
I agree with bookworm in that Mode C is just about every bit as good as Mode S.

However I don't think Mode A is much good because

a) ATC gets no FL readout to confirm what you told them so level busts are much less likely to be detected;
b) TCAS systems in airliners (and who-ever else has them fitted) don't work;
c) there are spurious TCAS warnings;
d) unverified (i.e. non-radio) traffic emitting Mode A and busting CAS whose base is above ground level is necessarily assumed by ATC to be below the CAS, which so far has been OK (no GAT-CAT midairs) due to luck and nothing else, plus of course any airproxes will be undetected unless the pilot gets a visual

As I has said here before many times, if Mode C had been made compulsory in the "obvious" terminal areas (like they do in the USA), many years ago, the fuss would have died down long ago, pilots would be routinely trained by the PPL training sausage machine to fly with Mode C (why? - because they have to :ugh: ), any plane not fitted with Mode C from day 1 would be useless for all except the most local bimbles, and due to the widespread usage of Mode C there would be a lot less pressure for "all" of GA to install Mode S. We would be muchless likely to have the present situation where a lot of traffic which usually flies very locally (e.g. gliding) is having to look at it.

In my view, the use of Mode C is a reasonable quid pro quo for

a) being able to get CAS transits,
b) being able to use the hugely error-prone map+compass navigation techniques anywhere, close to CAS and within CAS, in the absence of UK-style formal Mode C veils

Widespread Mode C usage also happens to make a radar information service (RIS) considerably better than the present RIS which, due to the majority of targets being non-C, is close to useless. OTOH one could argue that the sky is big so why use a radar service at all?

One problem is that GA (not just UK but all over Europe; remember Mode S is a European initiative) digs itself into the deepest possible hole over the smallest thing, so that when a battle is lost it results in the loser getting decimated, Roman-style. It is a reasonable strategy when fighting a local planning issue which will otherwise result in an airfield closure, but in this case one needs to be more subtle about it. The environment here is dictated from Europe, where airline interests rule the committees.

HEATHROW DIRECTOR
6th Aug 2006, 09:14
<<There are currently no terminal/approach radar systems in the UK (except Heathrow?) which have Mode S>>

Heathrow Approach Control uses the same radar facilities as the London TMA and the Approach Controls for Luton, Gatwick and Stansted. Heathrow Approach also controls a great deal of Northolt Traffic. These control functions are located in Terminal Control, West Drayton. Thames Radar (Approach Control for London City and Biggin Hill) and the Heathrow Special VFR Director are also located there and use the same radar equipment.

Speaking as a retired controller who spent many years working light aircraft on 119.9 I would say that any system which provides accurate information to ATC has to be worthwhile for all users.

SkyHawk-N
6th Aug 2006, 11:03
Widespread Mode C usage also happens to make a radar information service (RIS) considerably better than the present RIS which, due to the majority of targets being non-C, is close to useless.

"Close to useless"? a bit of an extreme view IMHO. I'd rather be told there was traffic in my vicinity even if in reality there is no factor due to it's altitude. I usually fly in a glider and military 'rich' environment, types which climb and descend very quickly and I would imagine that ATC would have a very hard time informing us of the exact situation at a moment in time. To be informed there is traffic in my area with a half decent range accuracy is good enough for me.

Why is this "Close to useless"?

'any plane not fitted with Mode C from day 1 would be useless for all except the most local bimbles'? Define a 'most Local Bimble'?

IO540
6th Aug 2006, 12:17
On a given 150nm flight in the south of England I might get 50 traffic reports (from say Farnborough/Brize/Shawbury) of which I guess 80% are "unknown level". How useful that is is a matter of opinion but it's an awful lot of resource wasted, on both the ATC and the pilot end of things.

From those that I do spot, and from the fact that I usually fly as high as I can without getting an IFR clearance into Class A (which complicates matters unnecessarily) I "know" most of them are way below me.

By "local bimble" I meant flight within a narrow range of one's airfield. With most UK airfields, one cannot venture very far in any one direction without reaching CAS. If Mode C was mandatory, you can bet that almost every plane that has a normal electrical system would have a Mode C fitted - simply because it would otherwise be all but useless for training or for self fly hire. If one had the US-style Mode C veils, while it would still be possible to fly a long way without needing a transponder, in practice one would choose to not restrict the utility of the plane to such a degree.

It's curious to observe that in America, often described as the land of aviation freedom, they have mandatory Mode C in the "obvious" places, while in Europe everybody has been fighting it.

SkyHawk-N
6th Aug 2006, 12:32
So you should have said 'close to useless where I regularly fly'. :}
I fly mostly around East Anglia and across to the Midlands. I find RIS very helpful and guess that the majority of the traffic reports are of traffic NOT being controlled by any ATC unit, gliders being the main 'culprits'. I never rely on RIS but to have someone else looking out for me as well is very welcome.

Sedbergh
7th Aug 2006, 11:47
I find it interesting that the CAA RIA quoted the 1999 Tornado/Cessna midair as their example of what Mode S could avoid (4 deaths @ £1.4 million each) - plus the cost of a new Tornado of course.

Is this actually a valid example?

The Cessna is said to have had a transponder, but it was switched off.
The collision occurred at 650 feet AGL in open airspace. IF the Cessna had been fitted with Mode S, would an FIS controller have been able to see it (by radar) at that level? Would an FIS controller have had time to warn the Cessna pilot of an impending collision?

Would the FIS controller have been able to see and contact the Tornado?
The Tornado did not have TACAS and as far as I understand, the RAF are not about to fit it.

The accident investigation report made six recommendations as to how the accident could have been avoided. The sixth (and last) recommendation covered improved technology (strobe recognition and Mod S).

So at that time the CAA were not hanging their hat on Mode S as the wonder cure. Now it seems they are.

Views please?

gasax
7th Aug 2006, 12:17
For one reaqson or another the CAA seem smitten with the idea of Mode S. you only have to glance at the material on their site to see have the arguement for it is spun to make it all things to all people.

Will it improve the lot of GA - of course not - we will either be filtered out or as now occurs ignored out in the FIR.

However none of that matters - this group of people have identified their next project and if a few things have to be bent to make the argument fit - who cares - they apparently don't.

The arguments against are all main based on cost and practicality which does n't seem to much bother the CAA. At its heart I suspect their is a desire to be seen to be doing 'something', to do 'something' that might be seen to lead Europe, to do 'something' which will stop them looking like a branch office for EASA. Oh and it might open the way for charging by the hour for the use of the air and other innovative uses of technology.

Will it make GA any safer - highly unlikely unless the military also have to fit ACAS and there are real improvements to air traffic services for ATC - which of course would cost money...........................

NorthSouth
7th Aug 2006, 12:45
The Cessna is said to have had a transponder, but it was switched off. The collision occurred at 650 feet AGL in open airspace. IF the Cessna had been fitted with Mode S, would an FIS controller have been able to see it (by radar) at that level?Probably not, because as the report states:
"Analysis of the recordings of local military and civil radars failed to show traces of the tracks of either aircraft. It is considered that this was because both aircraft were below the base of primary radar cover and neither aircraft appeared to be using its secondary radar transponder." (SSR has a base level too and they'd have to have been above that)

Would an FIS controller have had time to warn the Cessna pilot of an impending collision?Probably not because (a) on a FIS the controller could only have guessed which radar contact (if he could see one) was the Cessna, (b) both the Cessna and the Tornado would have been unverified, (c) traffic on a FIS unlikely to be given traffic info except in very general terms, and (d) in circumstances where a light aircraft and fast jet are on a collision course, giving traffic info to the light aircraft is highly unlikely to resolve the conflict since the conflicting FJ could be anywhere in the light a/c's 360 degrees and the light a/c can't move quick enough to get out of the way. Give tfc info to the FJ and you have a chance of resolving - except when the pilot's heads-down changing frequency as I believe he was thought to be in this case.

Would the FIS controller have been able to see and contact the Tornado?Only if the Tornado pilot was in contact with that particular controller. Otherwise it would have required a phone call to the controller whose squawk the Tornado was wearing or, more likely, a feeling of helplessness at an observed squawk of 7001 which indicated that the Tornado was in the low flying system and therefore almost certainly talking to no-one.

Well done for spotting a debatable case in the CAA's RIA. Is someone doing a thorough analysis of all the quoted cases to see how many others there are?

Another factor in this case is that it implies that in future Mode S will allow LARS controllers to provide a RIS to everyone previously getting a FIS - or that TCAS will sort everyone out. On the first, what do all you LARS controllers think about the workload implications? On the second, NB this is not an argument for Mode S, it's an argument for current ACAS and Mode C.
NS

chevvron
7th Aug 2006, 12:59
Firstly as LARS controller, I don't want my radar display swamped with unnecessary SSR labels. We already have problems with label overlap and one only has to watch the gliders out of Lasham on their competitions this week to see how close together they are and how close the labels will be, rendering the SSR returns useless.
Secondly, has everyone seen the reports in todays papers about all road vehicles being fitted with tracking devices ostensibly for taxation purposes? Well it strikes me a Mode S transponder could be used by an unscrupulous government (if we ever had one) to monitor and thereby impose taxation on all airspace users. Course it could be argued that they are necessary for security reasons, but then you only have to read reports about people using false number plates to get round Red Ken's congestion charge to realise that someone somewhere will eventually invent a 'false identity' attachment for mode S transponders.

englishal
7th Aug 2006, 13:39
Well I don't mind Mode S if I get something in return. If I could be provided with traffic info services similar to what you get in terminal airspace in the USA by virtue of myself having a mode S transponder, then I think it is a good investment.

As for costs, and portability, have a look at:

this (http://www.hamradio.co.uk/kinetic-last.shtml)

http://www.hamradio.co.uk/images/kinetic/last/lastscreen.gif

I personally think it is a good thing for all traffic to transpond, though I tend to agree that rather than force Mode S down everyones neck, I think the sensible option would be to implement Mode C vales around commercial airports.

IO540
7th Aug 2006, 13:59
Anybody can reconfigure a Mode S transponder, to show any identification.

Getting into the factory config is just a matter of holding down a button while the unit powers up, and the maintenance manuals are freely available.

I don't think this would be a lot of use for revenue collection, not because a lot of people would fly with "fake number plates" but because the radar coverage isn't there (not by a very long way) and nobody will even dream of paying for any enhancement to it just to collect enroute revenue from UK's barely significant GA population.

robin
7th Aug 2006, 14:05
Counsel of perfection, I'm afraid

I think we are all just too cynical about what we will get from Mode S expenditure when the infrastructure is just not there and the ATCOs themselves are getting nervous about the way their screens will work in future with everyone transponding

Flying a PFA machine I have no option but to plan my routes so I don't overfly congested areas and rarely get any service from the Mon-Fri only LARS service

At weekends I talk to the air-ground operators at (say) Compton Abbas, Old Sarum, Popham or Wycombe and give traffic information. They are just not equipped (or permitted) to give meaningful information, except to watch out for local traffic. Mode S just won't make any difference

gpn01
8th Aug 2006, 12:41
I find it strange that the rest of Europe isn't mandating a change to Mode-S.

If there's a demonstrable benefit (e.g. cost saving or improvement in safety) then why isn't Europe driving this 'initiative' ? The drive is not by EASA (= European Aviation SAFETYAgency) but by the CAA who probably see their existing role diminishing as EASA takes on more responsiblities.

Could Mode-S, and its regiulation, provide the CAA with a purpose to exist post-European harmonisation ?

NorthSouth
8th Aug 2006, 13:53
I find it strange that the rest of Europe isn't mandating a change to Mode-S.It is. There's an ECAC mandate for Mode S, leading ultimately to ADS-B. In addition there's an ICAO Standard that all aeroplanes and helicopters should carry a transponder. The UK's filed a difference from that for years but the CAA has now committed itself to following ICAO SARPs wherever possible.
NS

gpn01
8th Aug 2006, 21:45
It is. There's an ECAC mandate for Mode S, leading ultimately to ADS-B. In addition there's an ICAO Standard that all aeroplanes and helicopters should carry a transponder. NS

The existing ECAC mandate is for aircraft above 5700kg/19 pax though isn't it ? (http://www.eurocontrol.int/msa/gallery/content/public/documents/acas/TF%20Final%20Report%20-%20Version%201.0.11SEP03.pdf) .

I couldn't find details online about an ICAO transponder standard (although I did find http://www.airservicesaustralia.com/pilotcentre/projects/adsb/icaomeeting/2004/WP20_Maturity%20of%20ADS-B%20Aus..pdf which is an ICAO report on the immaturity of ADS-B). In any case, I thought that the ICAO standard was for aeroplanes (which isn't necessarily the same as aircraft).

NorthSouth
9th Aug 2006, 09:03
The existing ECAC mandate is for aircraft above 5700kg/19 pax though isn't it ?Yes you're probably right - what are other ECAC states doing about extending the Mode S requirement to all aircraft/all airspace?
I couldn't find details online about an ICAO transponder standard...In any case, I thought that the ICAO standard was for aeroplanes (which isn't necessarily the same as aircraft).The Danish SLV has helpfully put all ICAO annexes on their website at http://dcaa.slv.dk:8000/icaodocs/
The generic transponder requirement is in all three parts of Annex 6, so applies to air transport and GA aeroplanes and to helicopters - "All aeroplanes/helicopters shall be equipped with a pressure-altitude reporting transponder". UK has filed a difference to this, stating that they'll apply it when Mode S comes in. My only question is, since ICAO Annex 6 only applies to International Commercial Air Transport - Aeroplanes, International General Aviation - Aeroplanes and International Operations - Helicopters, does this mean ICAO SARPs don't apply to any aircraft which is not flown internationally?
NS

bookworm
9th Aug 2006, 15:29
My only question is, since ICAO Annex 6 only applies to International Commercial Air Transport - Aeroplanes, International General Aviation - Aeroplanes and International Operations - Helicopters, does this mean ICAO SARPs don't apply to any aircraft which is not flown internationally?

ICAO SARPs only apply as adopted by local law. The deal is that if you're equipped according to the ICAO SARPs, you should be permitted to fly internationally without having to jump through hoops related to every state you want to fly over. But the local law can exempt anything from ICAO rules for flight within its sovereign airspace as it sees fit.

gpn01
9th Aug 2006, 22:49
Iif you're equipped according to the ICAO SARPs, you should be permitted to fly internationally without having to jump through hoops related to every state you want to fly over. But the local law can exempt anything from ICAO rules for flight within its sovereign airspace as it sees fit.

So, if the future scenario is that the whole of UK aviation (that's EVERY glider, light aircraft, microlight, balloon, hang glider, UAV, helicopter and ultralight) is entirely controlled, as the CAA would like it, by Mode-S equipped facilities then a German Cessna 172 decides that he wants to fly to the UK will he/she need a Mode-S tranponder fitting ?

IO540
10th Aug 2006, 07:27
Yes, he will upon entering UK CAA airspace, unless a temporary visitation exemption is available.

This is already the case for loads of other equipment, especially for IFR. Take the old ADF thingy. The CAA requires it for IFR in CAS, but few other countries require it. Germany requires an ADF for some night flight IIRC.

ELT is another. Some countries need it, some don't. All N-reg planes have to carry it, worldwide.

The equipment carriage rules across Europe are an absolute nightmare, and are "obviously" widely flouted without anybody (the pilot in particular) realising.

To date, anybody flying IFR will have been generally aware of the need to carry various bits of variously expensive kit if they want to fly around Europe. Now, with Mode S, attention of VFR pilots is being drawn to it.

One would have thought that JAA would have unified the rules but they haven't. The nature of politics is that local exemptions have to be allowed in order to get anything agreed. EASA, taking over from JAA, is likely to simply force a lot of stuff through.

N-reg owners tend to be more aware of this than most, not least because the rules are more clearly stated.

bookworm
10th Aug 2006, 10:04
So, if the future scenario is that the whole of UK aviation (that's EVERY glider, light aircraft, microlight, balloon, hang glider, UAV, helicopter and ultralight) is entirely controlled, as the CAA would like it, by Mode-S equipped facilities then a German Cessna 172 decides that he wants to fly to the UK will he/she need a Mode-S tranponder fitting ?

I think it extremely unlikely that he/she would need one "fitting" as I would be very surprised if German requirements were less onerous than our own.

Note that according to ICAO SARPs, as NS suggested, altitude-reporting transponders have been required for all flying machines for at least 5 years.

By the time the Mode S requirement comes in, I imagine this will all be within EASA's remit.

Sedbergh
10th Aug 2006, 12:44
From reading the PFA and BGA responses to the Mode S proposal it appears that the French and the Germans are NOT proposing to make transponders compulsory in open airspace, but only in CONTROLLED airspace (which makes sense because all concerned will be in touch with ATC anyway)

The CAA seem to be alone in the folly of wanting everything that flies to have transponders in uncontrolled airspace.

I wonder what would happen if every light a/c, glider, microlight, VLA etc had a transponder and then asked for RIS in open airspace. How long before the system collapsed? 5 minutes??

robin
10th Aug 2006, 13:43
.
I wonder what would happen if every light a/c, glider, microlight, VLA etc had a transponder and then asked for RIS in open airspace. How long before the system collapsed? 5 minutes??

It is becoming clear that we are not to get any additional service or access to CAS just through carrying Mode S. ATC will 'dial us out' unless we get close to bothering them.

Even ATCOs are saying that they are going to have real trouble with this one, and don't want it, except in the areas that concern them ie close to their airfields or commercial traffic

Parapunter
14th Aug 2006, 08:20
I agree that this is important Mr Sedbergh. I'm a member of the hang & paragliding communities, just one of around eight thousand in the UK & half a million or so Europe wide. This proposal from the CAA could very well represent the end of competitive cross country flying in the UK for us since the kit represents a severe weight & cost penalty for our ultra light aircraft.

Whilst we only fly for leisure, it's estimated that 2,000 jobs will be at risk from this proposal & the end of a thirty year sporting heritage could be made reality. Naturally, we seek exemption from the proposal & the associated costs of implementing it. Thus far, we have seen price proposals of 1000-1500 GBP per unit with a 3-400 GBP annual oncost for servicing of the transponder units. To put it in context, that represents over 50% of the purchase price of our gliders!

Instead, we would prefer to illustrate our discipline in the light of our well established controlling body, the BHPA & our strict & thorough pilot rating scheme which gives those pilots flying beyond our soaring ridges the skills & awareness to mix safely with our powered brethren.


Say no to mode s Transponders!


Edited to add: I should point out that I speak only for myself & represent no part of our sport other than my own bimbling around the sky.

robin
14th Aug 2006, 09:14
Just seen Max Seaman's response in Loop. I have great respect for him in my dealings with him.

However, here is what he says about the price of kit:

"You state that a transponder is going to cost £2000, but make no mention of the Low Powered SSR Transponder (LPST) that the CAA would like to see marketed at £500-£1000"

Well, where is it? and what are the CAA doing to ensure that the price is at the lower end of the spectrum?

It seems the only people the CAA wish to exempt from carriage of Mode S are parachutists

jabberwok
14th Aug 2006, 14:24
I could point you to one such device but forum rules probably don't allow it.

Try an oogle search for "Lightweight Mode A/C/S Level 2 Transponder with ADS-B". That should take you straight to the page.

Choxolate
14th Aug 2006, 14:45
One of the things that worries me is the format of the "consultation" document.

Basically it is divided into sections with a series of questions and multiple choice answers, e.g. one question is "Need to improve collison avoidance measures" - Strongly Agree to Strongly Disagree with this as an aim.

Is there anybody who thinks we should not try to improve collision avoidance?

So a tick in the agree box.

Now all the boxes will be added up and the CAA will say that over xx% agree that Mode-S will improve collision avoidance - OH NO THEY DIDN'T - they agreed it should be improved but not HOW.

This method of consultation applies through the whole document and will give the answer they want.

Yes there is space to write comments but I am sure these will not be used for any quantitative analysis.

robin
14th Aug 2006, 14:54
I could point you to one such device but forum rules probably don't allow it.
Try an oogle search for "Lightweight Mode A/C/S Level 2 Transponder with ADS-B". That should take you straight to the page.

If you are talking about the first entry - they would find it hard to get below £1500

VP959
14th Aug 2006, 16:00
Indeed, the one referred to is £1500 plus VAT, which makes it closer to £1800, rather than the "£500 to £1000" referred to by the CAA in the RIA. As it looks like being the only one on the market, why should they reduce the price? It certainly wouldn't make economic sense when they have a captive market that absolutely have to buy the things under a provision of the law. In fact, my inclination if I were this company would be to put the price up, as people will still have to buy them if they wan't to keep flying................

VP

IO540
14th Aug 2006, 16:41
The "confidential" end user list price of a GTX330 is about £2000+VAT. Installation is on top and will range from £300 to replace some existing transponder, to a lot more for a complete brand new setup.

A cheap transponder won't help with the installation cost.

The only way to make this whole business "cheap" is to have a portable transponder, which can be strapped somewhere or installed by the pilot.

The moment an avionics shop is involved, nothing much happens under a grand if it involves drilling holes, fitting aerials, and running wires.

I still can't believe they are going to mandate Mode S for everything that flies. Quite bizzare.

Lucy Lastic
14th Aug 2006, 18:47
The "confidential" end user list price of a GTX330 is about £2000+VAT. Installation is on top and will range from £300 to replace some existing transponder, to a lot more for a complete brand new setup.

A cheap transponder won't help with the installation cost.

The only way to make this whole business "cheap" is to have a portable transponder, which can be strapped somewhere or installed by the pilot.



I've been told that the LPST mentioned needs a chip installed in the aircraft circuitry to uniquely identify the aircraft (for charging purposes??). Although the LPST is portable, the chip isn't, and will need installation, maintenance and calibration - all at a price.

On the RIA is says that if all aircraft (gliders, microlights and fixed wing) get Mode S, 13000 aircraft will need to be fitted, have annual checks, and get fixed when it goes wrong.

Do we actually have enough avionics engineers willing to do this?

VP959
14th Aug 2006, 20:57
My previous price was wrong, it's £1500 including VAT, not plus VAT.

The number of aircraft affected is a lot more than 13,000. According to the CAA's own GA review figures there are more than 27,000 affected aircraft in the UK fleet. 26% of these are un-registered, deregulated types (hang gliders, paragliders, powered hang gliders and paramotors), 21% are SEPs, 15% are microlights, 10% are gliders, 7% are balloons/airships, 6% are PFA types, 6% are helicopters and gyroplanes, 4% are commercial air transport, 2% are private multi engined, 2% are vintage or historic and 1% are private turbine.

The recreational aircraft sector is about 75% of the UK fleet, perhaps a little more, and is composed mainly of very light aircraft with little or no capability to carry a transponder.

With an assumed unit cost of £1500 (as this is what the only unit available is priced at), then the cost of fitting all 27,000 aircraft will be over £40M, excluding installation, inspection, approval and licencing costs. Even allowing for perhaps 10% of the fleet that already have Mode S, the cost still greatly exceeds the £20M figure beyond which regulatory impact statements have to be submitted to the Prime Ministers Office.

The CAA are pulling a fast one here, as they seem to have deliberately set the assumed unit price of a transponder, plus the affected aircraft fleet size, at figures that come in below the magic £20M.................

VP

Lucy Lastic
14th Aug 2006, 21:15
So why doesn't that surprise me?

IO540
14th Aug 2006, 21:42
I've been told that the LPST mentioned needs a chip installed in the aircraft circuitry to uniquely identify the aircraft (for charging purposes??).

A Mode S transponder is indeed programmed with a unique number which decodes to your tail number.

However, Mode S cannot be used for enroute charges because of unsufficient radar coverage (in the context of normal low-level VFR flight). This is a common myth going around this business.

There is no "chip" as such; a transponder is full of chips :) The programming of the Mode S code is trivial; you can do it yourself (although you aren't supposed to ;) ).

Myndflyer
15th Aug 2006, 15:24
Also buried deep in the consultation document is the idea that these ModeS Transponder units they are mandating we fit WILL ONLY BE CERTIFIED FOR VMC USE.

Maybe I've read it incorrectly, but I presume this will mean NO MORE of the following:
Gliding in wave / climbing to the top of a thermal ie within 1000' of cloud (ie IMC) / no more flying on an even slightly hazy day. Am not sure of the effects on IMC flight / night flight.

Yes there's the cost issue, but surely THIS is an even more important issue that could stop virtually all recreational non-powered flying as we know it? :mad: :ugh:

Parapunter
15th Aug 2006, 15:36
Indeed & I can't imagine the usefulness of transponders under the conditions below. I guess it would wear them out in a matter of hours - I think perhaps this hasn't been thought through from a free flight perspective...

http://i7.tinypic.com/24o9ag2.jpg

Aunt Rimmer
15th Aug 2006, 16:20
I work as an ATCO on several airspace sectors at Scottish Centre.

Believe me, the screens are cluttered enough at the moment especially when trying to distinguish 'your own' traffic at say FL100+ from low level VFRs or helicopters.

On a 16 inch monitor on 250 mile sector, it does not take a rocket scientist to work out that the SSR labels on each aircraft can be 15 miles across.

Well seen the dire state of the UK Air and Space Industry as there are obviously no rocket scientists within the CAA.

<rant on>
IMHO there are too many deskbound pen pushers who have never tried to..

a)separate aircraft for a living using the rules THEY create :8
b)operate an aircraft in the crazy overtaxed and over-regulated UK environment :{
c)use the crap equipment at Scottish Centre :mad:
d)understand that not everyone actually needs to be 'controlled' - (we don't all have to be identified VFR actually works quite well.) :ugh:
e)understand the needs and rightful freedoms of GA :mad:
f)think how badly cluttered radars will become if EVERYONE puts up a Mode S response. :=
g)think that while Mode S is a good idea in a Class A TMA environment, it is not appropriate to burden users in Class G airpspace. :=
h)think that it won't work below radar/radio cover in mountains and valleys :hmm:
i)won't solve the real 'collision' issue of military aircraft without TCAS :D

Just my £5 worth :*

<rant off>

Rod1
15th Aug 2006, 16:35
If mode S had been fitted how many lives do you think would have been saved in GA aircraft in a three year period. NONE!

Remind me again why we are doing this?

Rod1

Pitts2112
15th Aug 2006, 16:56
Folks,

I think we're really all missing the point in this. We're having the wrong argument. Most of the discussion I've seen here and in other places is about the practicality and cost of installing this in our light aircraft, with the implication that everyone has accepted that it is a done deal. I haven't seen the most fundamental question really addressed in any kind of robust manner, which is:

Where is the sound, data-driven, and solid business case which justifies the requirement of Mode S in light aircraft?

So far I haven't read anything (and, admittedly, my research is very superficial) which shows data, charts, graphs, UK accident history, and a whole shedload of facts to support this requirement at all. Until the CAA makes its case for it, I think dicussions of technical problems, cost and practicality are premature and give the CAA the impression that we're accepting we need it, we're just arguing over the cost.

The UK does not have a history of aircraft mid-airs, near-missses, or even serious separation problems which would make this an undeniable case. I simply fail to see how Mode S in a Tigermoth or PA28 addresses any safety problem because there doesn't appear to actually be one.

Am I missing something here? Are we, in fact, having the right argument and I'm just not clued in?

Pitts2112

robin
15th Aug 2006, 18:24
I'm afraid the issue is that the pressures are on the CAA and NATS to allow routings through the open FIR by commercial jets who still want radar separation on the grounds of 'efficient use of airspace'. They also want to move towards a charging regime for the use of airspace which is another reason why the lo-cost operators are choosing not to use airways

Remember that the CAA has no brief for GA and a notorious lack of understanding of the effects of their decisions.

The RIA is based on an assumption that all traffic in Class G is talking to someone - well, we're not. Partly because we may choose to use the nearest A/G station as LARS isn't working, or because we are simply non-radio (not illegal, yet)

Read the article by Max Seaman in this month's LOOP and see the line the CAA want to go

VP959
15th Aug 2006, 19:58
Max Seaman is a reasonable chap, but I have to say that his portrayal of the party line from the CAA, complete with gross innaccuracies on things like unit cost, did really make me wonder a bit.

It's clear from the contents of the proposal in the RIA that the CAA consider this a done deal, and that we should all just bow down and accept it.

They really seriously need to get their head around the biggest growth sector in UK recreational aviation and try to see how the heck they are going to implement this regulation. 26% of the UK aircraft fleet is unregistered, unregulated and flown by pilots with no CAA issued licence. I'd just love to hear how they are even going to know of the existence of these aircraft, let alone try to track them down to ensure compliance. I've got a couple like Parapunter, does this mean I need to buy two transponders?

It's plain barking. The class G airprox statistics simply don't support the argument for transponders in any way, shape or form. The CAA are being driven to do this by the argument being put forward by budget carriers like Ryanair and Easy Jet, who wish to avoid airspace charging by operating in "controlled" class G for approaches to cheap out-of town airports.

VP

PPRuNe Radar
15th Aug 2006, 20:22
The CAA are being driven to do this by the argument being put forward by budget carriers like Ryanair and Easy Jet, who wish to avoid airspace charging by operating in "controlled" class G for approaches to cheap out-of town airports.

VP959

Both yourself and Robin misunderstand how charging works outside controlled airspace. If you are IFR above 5700Kg, then you are charged regardless by way of the en route charge. The UK unit charge rate is the same whether in Controlled Airspace or not, and whether or not you receive an ATC service.

Whether you interpolate that Mode S might be used to charge VFR flights, or those under 5700Kg, is a different argument.

VP959
15th Aug 2006, 20:57
Good point about airspace charging, my error.

The issue is still the same though, in that the low cost carriers are applying pressure to the CAA to increase safety when making "VFR" approaches through class G. Even the CAA admit that this is one of the reasons they want to see Mode S mandated for all flying machines.

VP

bookworm
15th Aug 2006, 22:27
Both yourself and Robin misunderstand how charging works outside controlled airspace. If you are IFR above 5700Kg, then you are charged regardless by way of the en route charge. The UK unit charge rate is the same whether in Controlled Airspace or not, and whether or not you receive an ATC service.

Your point is a good one, but on a point of detail, charging applies to IFR traffic above 2000 kg and all traffic above 5700 kg.

Pitts2112
16th Aug 2006, 05:29
I've just finished reading the RIA and it does look like the CAA are convinced this is not only a good thing but the ONLY thing they can do and we should just accept it and start saving up for the installation bill.

The facts and data they give just do not substantiate a programme of this magnitude. The number of total airproxes in an 18 month period (Jan 04 to Jun 05) was only 299. Of those, only 200 would have benefited from some sort of TCAS or Mode S and only 100 took place in Glass G airspace, where most of us operate.

What their data does not say is who these incidents were between. How many were between GA and Commercial Air Transport (CAT), between GA and Mil, Mil to CAT, Mil to Mil, CAT to CAT, or GA to GA. In other words, we don't know what proportion are even related to our aircraft, regardless of the airspace use. Irrespective of the argument about how many incidents are relevant, we're still talking about only 200 out of how many flights took place in that 18 month period.

What I am missing right now, to make my point to the CAA that their case is negligible, is the number of movements of GA, Mil, and CAT. Let's say it's only 100,000 flights per year and let's not even add any multiplier about how many flight paths might cross on each flight (ie - creating a potential airprox but didn't). Of 100,000 flights, only 200 were relevant to Mode S/TCAS, for a total problem set of 0.2% and only 34 of those disrupted commercial operations somewhere.

The other thing is what is the expected growth rate of GA in the next 10 years? Everything I've read lately is that we're becoming a dying breed so the likelihood of incidents involving us should be diminishing over time.

The CAA makes sets no quantifiable target for improvements to safety. Will Mode S take the number from 299 to 199, 150, 0? They don't have a target, which means they don't know how effective it will or won't be. Which also means it could do absolutely sod all for these incidents and they won't be held accountable for an unnecessary and ineffective programme. If they can't quantify a target then they don't really know if it'll have any effect at all. I wouldn't sign off a business case like that in the corporate world.

Finally, Mode S for seperation implies that at least one party is talking to someone on the ground. I never talk to anyone, preferring not to use their airspace and take up their time. What percentage of GA flies like that? Would the various ATC providers be able to hande the volume of traffic that would have to talk to them for Mode S to have the intended value?

So, a question. Does anyone know where the data may exist for the total number of aviation movements in the UK per annum? Also, has anyone seen any official projections on the growth of GA in the UK?

Many thanks and please get involved and make your point to the CAA. Their case has not been made, regardless of how much it'll cost to put one of these things into your airplane. Let's have THAT argument before we talk about cost and practicality.

Pitts2112

PPRuNe Radar
16th Aug 2006, 06:36
Thanks Bookworm for the correction :ok:

Like most others, I am not convinced by the safety argument that Mode S is required everywhere.

For operations within Controlled Airspace, then I can see the point of Mode 'S', although it should not be beyond the wit of man to allow some dispensations for specific operations. The operator and the controlling authority would formulate a letter of agreement which laid down the conditions for operation without Mode 'S', one of which could be Mode A & C instead, or it could be by treating defined airspace as a Temporary Restricted Area with non Mode 'S' operations within it. This would allow things such as parachute operations or gliding.

For operations close to major Controlled Airspace or specific airfields in Class G without Controlled Airspace, then I think the 'veil' is a good idea. If it is a Mode 'S' veil, then it might not suit all operators but it's at least a bit of a compromise. The size of the veil could be pragmatic, small enough to unhinder some GA operations, but large enough to provide adequate protection from traffic operating close to the edge or infringing. 5-10 miles would be my view.

Some thought would also need to be given as to whether it is also required above a certain altitude outside Controlled Airspace, or whether we just wait for the European programme which will bring Controlled Airspace down to lower levels globally (FL195 soon, a lower level such as FL95 being mooted for later) and then have a Mode 'S' requirement by default based on my initial 'requirement' proposal. This would not affect the major proportion of powered GA, but would still need some debate as to how gliders might be accomodated.

Choxolate
16th Aug 2006, 08:39
This may be a completely stupid suggestion but the main aim is for Commercial traffic to have ATC control in what is currently "open" FIR - if this is wrong then skip to next post.

The GA, paragliding, ballooning fraternity etc. mostly use open FIR hence potential conflict, hence suggestion of Mode S.

However a huge percentage (90% - 95%?) of the above GA et al are below 10,000 ft and the majority (90-95%?) of commercials are above 10,000 feet. Why not just make all UK airspace over 10,000 feet controlled (Type B?) in which a mode C (not S) transponder is mandatory?

There must be some fault in my logic but it would seem to fit the requirements of all and would cost bugger all to implement.

Parapunter
16th Aug 2006, 08:51
Just on PG & HG, I can say that 95% of all pilots actually only ever fly on the ridge from whence they started. Only a very small number will climb high enough to enable a cross country flight & in nearly all cases not in excess of 5,000` AGL, although recently, the UK pg height gain record was broken with a climb to something like 3,400 metres followed by a 40k glide - the exception that proves the rule.

Realistically, us lot are unable to transit controlled airspace to atco's requirements & thus are effectively excluded & so yes, we fly largely in the open FIR, transiting under & over aerodromes as required by current regulations. From my viewpoint therefore, transponders are costly in both weight & financial terms & unneccesary for the regulation of our activities.

I'm watching this thread with interest & I would like to see an argument in support of these things, in order that I may understand the CAA view - doesn't seem to be many participants in favour so far?

slim_slag
16th Aug 2006, 09:15
Why not just make all UK airspace over 10,000 feet controlled (Type B?) in which a mode C (not S) transponder is mandatoryVery sensible suggestion, with the exception of airspace class, this has been succesfully implemented elsewhere using Class E (no requirement for VFR traffic to talk to ATC). If ATC sees a non-radio VFR target then they can just vector the jet out of the way. What I want to know is why do the Europeans want to try out these expensive new experiments out on their GA fleet when all they need to do is copy somebody else who has already done all the donkey work?

IO540
16th Aug 2006, 09:27
Assuming that the drive to transponders is being done to better manage the airprox situation (particularly the issue with CAS busts by non transponding GA) I don't think mandating Mode C/S above 10,000ft would help in the UK. Almost no GA traffic flies that high.

Even at 5000ft there is hardly anybody.

Adopting the US model, of Class E to 17999ft and Class A from 18000ft up, that would be something else, but nobody in the UK is going to be that bold. Even the French model, Class D above FL115, would be too much to swallow.

One would have to completely re-do the whole airspace thinking to do this.

Incidentally, referring to that paraglider picture above, is there a proposal to mandate Mode S for these? :ugh:

Parapunter
16th Aug 2006, 09:42
We are included in the proposal, yes.

robin
16th Aug 2006, 10:12
Then get your comments in soon.

Remember it is only by making a mass response that the CAA will have to take action to rethink the situation

They are planning to have the Full RIA (including the results of this one) ready during the autumn with proposed legislation by the end of the year.

So plenty of time for them to change their minds - not!

Note: there is a public consultation at Lasham Gliding Club at 19.00hrs tomorrow evening.

Pitts2112
16th Aug 2006, 10:41
Right, I've read the RIA and a few other documents to boot and come to these conclusions.

The total number of airproxes in an 18 month period (Jan 04 to Jun 05) was 299. Let's round that to 300 and take two-thirds to give us 200 per annum. Of those, only 150 or so would have benefited from Mode S/TCAS. Compare that to the CAA's own traffic statistics of total air movements of 3.8 million in 2005. Doing the sums, this means that less than .007% of movements involved a reported Airprox. This number is so small as to be negligible and certainly doesn't justify a capital investment programme of this magnitude.

The CAA have not quantified their targets for Mode S safety improvments. There is no estimate of benefit. Will Mode S reduce the 299 down to 200? 150? 0? If they can't put a number to it, it means they really don't know.

The CAA's airprox statistics do not differentiate where GA was involved. Of the 299, how many involved the GA fleet where Mode S would have been a factor? They're basing their case on a very small number which they have not completely explained. This becomes an issue when looking at the projected growth of aviation in the next 20 years. If the current problem is not with GA, then the future problem is unlikely to be with GA.

Overall, the CAA have not made a case for Mode S either substantiating the need or quantifying the benefit. This is going to be the basis of my response to them.

Pitts2112

IO540
16th Aug 2006, 11:13
Doing the sums, this means that less than .007% of movements involved a reported Airprox

The problem with that line of argument is that it is like saying that 0.007% of children left alone with an adult get sexually molested, so paedophiles do no harm.

Or, since there has never been a GAT/CAT midair, one should be able to dismantle all controlled airspace. Clearly, the evidence does not support the need for CAS at all.

One needs to approach it differently. How many MPs and Lords are involved in this sport? That is the key to everything in the UK - or anywhere else for that matter. Write to them. Write to your MP. No use complaining to the CAA.

The proposal for paragliders to carry transponders (I haven't read it myself so taking the above poster's word for it) is comparable in barmy-ness to the one from the DfT (which uses the CAA as its consultant on just about everything) to kick out foreign-reg planes out of the UK after a parking period of 90 days.

robin
16th Aug 2006, 11:35
[I]One needs to approach it differently. How many MPs and Lords are involved in this sport? That is the key to everything in the UK - or anywhere else for that matter. Write to them. Write to your MP. No use complaining to the CAA.
.

I'm copying my letter to the chair of the Transport Select Committee, Gwyneth Dunwoody. They did a good job on the CAA earlier in the year over the failure to address GA issues and they may be interested to see if they have changed their approach to GA

Unfortunately, though, there are signs that the Committee has swallowed the CAA's line that they are better placed to regulate than EASA and so are holding on to some of their old territory

Pitts2112
16th Aug 2006, 11:55
Doing the sums, this means that less than .007% of movements involved a reported Airprox
The problem with that line of argument is that it is like saying that 0.007%


One needs to approach it differently. How many MPs and Lords are involved in this sport? That is the key to everything in the UK - or anywhere else for that matter. Write to them. Write to your MP. No use complaining to the CAA.


You've got a point there on both counts. First, this is a highly emotive subject and, having worked at BA for 5 years, I know how easily people wrap the banner of safety around an issue just to get it passed and also how strongly people will defend that position from an emotional standpoint. I'm trying to get some data in my argument to take some of the emotion out of it.

The CAA need to come to the realisation that, while 0 Airproxes (even reduced) is a good goal, this proposal is not going to achieve it.

On the MP issue, that's a particularly good one. Does anyone know what stance Lembit Opik has taken? I've had no luck getting on to his website or anyone to answer the phone.

Pitts2112

Parapunter
16th Aug 2006, 12:08
Someone in our flying club has emailed Lembit Opik & he has undertaken to ask parliamentary questions.

For those who don't know, Mr Opik is a lapsed PG pilot. I believe he lapsed after flying consderably closer to the edge of the sky than is recommended, but it appears he retains an interest in gliding matters.

slim_slag
16th Aug 2006, 12:33
That document looks like it was once used to justify Mode S for airline use. Fair enough. What they appear to have done is decided it's time to force it on the rest of the world, and added a load of stuff about Airproxes (used over 60 times but not defined once).

Take out all the legitimate stuff for airlines and Mode S and there is nothing left of substance except the possible need for GA to have mode C near busy airports. They said you only needed Mode C too, not Mode S :)

Pitts2112
16th Aug 2006, 12:54
That document looks like it was once used to justify Mode S for airline use. Fair enough. What they appear to have done is decided it's time to force it on the rest of the world, and added a load of stuff about Airproxes (used over 60 times but not defined once).
Take out all the legitimate stuff for airlines and Mode S and there is nothing left of substance except the possible need for GA to have mode C near busy airports. They said you only needed Mode C too, not Mode S :)

That may all be the case, but don't count on the CAA coming to their own conclusions themselves. Help them see it.

slim_slag
16th Aug 2006, 13:13
The CAA have already come to their conclusions.

Section 2.2.2 gives the alternatives.If this technical interoperability is not put in place, the alternatives are to either segregate non-compatible users through restrictive airspace measures or to restrict traffic growth.These alternatives need to be described in greater detail and people given the ability to comment on them. The restrict traffic growth is obviously directed at the airlines, and they already have to use Mode S, so it's a stupid thing to say in this document.

What restrictive airspace measures would be required? That sounds like a threat to me, do this or else. They need to describe those changes as most GA people might not give a damn. People in the SE could install Mode C as the document suggests, the quid pro quo being a massive reduction in controlled airspace as there is no need for the ridiculous buffer zones around places like LHR and STN. Decreasing the amount of 'positively controlled' airspace would remove VFR choke points so satisfying their own objectives stated in para 1, which is to reduce airproxes.

Pitts2112
16th Aug 2006, 15:58
What restrictive airspace measures would be required? That sounds like a threat to me, do this or else. .

Agreed. It does sound like a veiled threat, but to whom is hard to figure out.

People in the SE could install Mode C as the document suggests, the quid pro quo being a massive reduction in controlled airspace as there is no need for the ridiculous buffer zones around places like LHR and STN. Decreasing the amount of 'positively controlled' airspace would remove VFR choke points so satisfying their own objectives stated in para 1, which is to reduce airproxes.

Well, that's exactly the kind of useful exploration of ideas that needs to happen. If the CAA invited the various representing bodies to join a working group to address the problems of separation and congestion, I think they might come up with better solutions than the CAA's Mode S one. I, for one, would really like to see that kind of consultation.

Pitts2112

slim_slag
16th Aug 2006, 16:11
You need to remove the forward slash from the first quote tag. Will read the document again, but the more I think about it the more I think it's a piece of well structured BS.

dublinpilot
16th Aug 2006, 17:12
With an assumed unit cost of £1500 (as this is what the only unit available is priced at), then the cost of fitting all 27,000 aircraft will be over £40M, excluding installation, inspection, approval and licencing costs. Even allowing for perhaps 10% of the fleet that already have Mode S, the cost still greatly exceeds the £20M figure beyond which regulatory impact statements have to be submitted to the Prime Ministers Office.

If this is true, then perhaps someone should explain to the Transport Minister, and to the Prime Ministers Office that the CAA are 'massaging the figures' (rather than a more confrontational term) to circumvent the Prime Ministers Office?

Annoyance coming from the Prime Ministers Office will get far more attention in the CAA offices, than annoyance coming from a load of GA pilots.

IO540
16th Aug 2006, 18:24
I don't see a problem with mandating Mode C/S in normal spamcans etc (much as this will annoy lots of people, but I've already given my reasons for this) but this business of mandating it much wider, to the "flying machines" that can barely install it or power it, suggests that the person who wrote this is the same clueless person who wrote the "Kick out N-reg" proposal.

I sometimes wonder if these people are hand picked to do a "hatchet job".

VP959
16th Aug 2006, 18:38
Precisely the point I made in my response to them a month or so ago, Dublin Pilot.

They can't argue with the 27,212 fleet size figure, as it's their own data, taken from the most recent GA review. They can't argue about the £1500 unit cost figure either, as that is the advertised price, including VAT, of the only available portable transponder, fixed units are slightly more expensive.

A quick, and extremely conservative, estimate of the absolute minimum real cost to the UK very light recreational fleet is:

Transponder purchase costs for the light recreational aircraft fleet that doesn't currently have a Mode S transponder fitted (about 60% of the total UK aircraft fleet, and includes most of the PFA fleet, all of the BMAA fleet, all foot launched aircraft, 90% of the balloon fleet and 80% of the glider fleet) = 16,260 x £1500 = £24.39M

Modification design and approval costs for approx 6,500 Permit to Fly aircraft and gliders (assuming about half the PFA fleet already have transponders of some sort fitted, around 500 gliders have them fitted and none of the BMAA fleet have them fitted) = 6,500 x £100 (a very conservative figure) = £0.65M
Initial installation, inspection and licence cost for 4,500 Permit to fly aircraft and gliders, at approximately £200 per aircraft (again, a conservative estimate) = £1.3M

Inspection and licensing costs for the 26% of the UK fleet that is deregulated, (around 7,000 aircraft, including hang gliders, paragliders, powered hang gliders and paramotors) = 7,000 x £200 = £1.4M

This gives a lowest possible cost, excluding the fitting of new wiring looms or antennas to affected aircraft, of £27.74M, just for the very light recreational fleet, excluding all the flying club SEPs, all the light twins, all rotorcraft and the historic and vintage fleet. Assuming that half of these aircraft need to have new transponders fitted will add another £7.8M to this, which increases the grand total to £35.5M.

Someone at the CAA has been unbelievably creative with the accounting on this, which either indicate incompetence on their part, or a deliberate attempt to circumvent the due process of government. If it's the latter, then, as a agency of the DfT they are in breach of their terms of reference, I suspect.
VP

robin
16th Aug 2006, 19:01
I think they are building into their calculations discounted prices, based on the fact that many owners will choose to go for the low cost version, when available

They are quite adamant that they are loking for a low cost product of between £500 and £1000, although there is no sign there is a manufacturer willing and able to do it for that sort of price

I've written to my MP on this and the chair of the Transport Select Committee, as I feel this is open to review. They already acknowledge uncertainty in costs, but still want to implement, and are bodging the figures to suit

Pitts2112
16th Aug 2006, 20:32
Folks,

Another though occurred to me today. Reading the RIA, the underlying message has nothing to do with Mode S, per se. The underlying problem is how to effectively provide safe separation of all the different types of users in the complex airspace of the UK, especially in the context of the projected growth in Commerical Air Transport demand (2-3x by 2030).

Mode S is a classic case of presentation of someone's solution rather than discussion of the problem. Anyone who's ever managed a project or tried to spec an IT system for a client will recognise the symptoms.

I think an effective alternative to Mode S for private aviation would be an open discussion with the representative bodies to address the real separation problem as a wider community so each can express their concerns and put their own ideas on the table, sort of a self-regulation approach, under the control of the DfT or CAA. It would have to be genuine debate and produce results, but my experience in doing this is you get a much stronger solution than by one organisation thinking it knows best for all. You also get much more creative solutions that the one organisation probably couldn't have achieved on their own.

I'm thinking that this proposal to MPs, the CAA, and the DfT, in concert with a robust response to the RIA, may have some mileage. Details need to be fleshed out of course, but this is my thinking so far.

Your thoughts?

Pitts2112

Aunt Rimmer
16th Aug 2006, 22:58
IO540 wrote .....I don't see a problem with mandating Mode C/S in normal spamcans etc (much as this will annoy lots of people, but I've already given my reasons for this)

Well IO540, as much as I agree with you on many issues, on this I bloody disagree. Do you have a vested interest in fitting or selling avionics ? :hmm:

By any chance is your flying, generally IFR long transits, at the 'expensive' end of single engine GA ? Are you always in and out of controlled airspace ?

IMHO
It WILL NOT improve safety, in fact, speaking as an ATCO, I am convinced it will clutter many many radar screens and potentially max out a lot of sectors.

It will NOT create a known traffic environment as it is not mandated for the military.

In areas with hills, valleys and poor radar cover (eg Scotland and Wales, which makes up 50% of the UK landmass) please explain which radar will see my mode S return. In fact please explain which RT transmitter will enable me to speak to anyone below 3000.

Do you have any idea how many aircraft operate outside controlled airspace at the moment without transponders ? It is sad, but I think many many ATCOs are really quite ignorant of how much flying actually goes on outside controlled airspace. And I speak from experience. I have detected a growing feeling (particularly since ATC privatisation) that anything other than 737s are just not important, and are only 'spamcans' or people with limited RT having 'fun', and therefore not worthy of attention. A bad bad bad attitude that ATC units do little to counter. :=

I use the example again of last months Strathallan flyin. 78 aircraft departed in 30 minutes. Most just went on their way. Now, if we all have to fit Mode S (for someone elses perceived commercial benefit) don't we then have a right to demand and expect a service for having been forced to comply .... ?

I guarantee that any radar unit would be unable to cope with 78 aircraft calling in that timescale. You couldn't even do simple RT let alone pass traffic info, and if you can't pass traffic info .. then what is the ####ing point of Mode S in the first place ? Unless it is purely to benefit the locos that want to cut corners outside controlled airspace and operate into small regional airports..... but these are often through areas of intense mil activity ... where the mil errr..... dont have to fit Mode S.

Doesn't seem logical to me.

Fitting Mode S is effectively a tax, and a bloody ineffective and expensive one too.

No tax without representation.... no there's a catchy slogan .... :D

Pitts2112
17th Aug 2006, 05:58
IO540 wrote .....
No tax without representation.... no there's a catchy slogan .... :D

A very good slogan! But be careful. The last time that one was used, Britain came out of it slightly worse for wear. :)

Pitts2112

Parapunter
17th Aug 2006, 07:45
Pitts,

My thoughts fwiw are that you've hit on the ideal course of action - I can report that our lot are lobbying for exactly that, exemption underpinned by dialogue & debate, as we have done with each and every previous issue that has threatened our continued existence - ultimately, we have a strong track record of self governance & we hope that that will prevail in our case. Nothing's guaranteed though & I'm heartened by many of the opinions I've read on here.:D

IO540
17th Aug 2006, 09:04
Well IO540, as much as I agree with you on many issues, on this I bloody disagree. Do you have a vested interest in fitting or selling avionics ?
By any chance is your flying, generally IFR long transits, at the 'expensive' end of single engine GA ? Are you always in and out of controlled airspace ?

No vested interest other than flying with an RIS (when I can get it) and I would like fewer "level unknown" traffic reports. I would imagine that you as an ATCO would also prefer to know the height of the return(s) when providing a radar service. You will know perfectly well that providing a pilot at FL50 with an RIS, and telling him - as the rules require you to - about every "level unknown" return doing about 70kt is probably a waste of his time and your time. It is highly likely that the return is much lower down.... but not certain. If everybody had Mode C/S then the most of the RIS radio traffic would go. To be fair, this won't happen because Mode S is unlikely to be mandated for many very slow or lightweight machines (simply because it's impractical) so these will still be around but I am sure your workload will still go way down.

Don't forget that a lot of people do have transponders and don't use them deliberately.

I do fly IFR across Europe too but that is generally under radar control and most of it is in CAS, where the problem doesn't arise, and anyway very few non transponding planes will be at FL100+. In fact there is close to zero GA at those levels.

I don't see a connection between having a working transponder, and working an ATC unit on the radio. It's immediately obvious that if everybody called up e.g. London Info, doing exactly what they were taught in their PPL, the service would collapse. A radar service with too many targets should not collapse; with Mode S you can turn off those that are at low level and nowhere near CAS. Those (much fewer, one hopes) that are busting CAS, or look like they are about to, you will want to turn back on :)

slim_slag
17th Aug 2006, 09:12
Well, there is so much BS in their draft document it's hard to know where to start. They are playing the safety card in their objectives, and obviously hoping nobody will notice that only a small part of the following 65 pages is relevant to this objective. Aimed at our elected representatives, and not people who might know a bit about the subject. On reading the document it is easy to lose the will to live, and I am sure they are relying on that too.

First, it's a Partial RIA, how can anybody comment on an incomplete document? so what are they hiding for the final edition? I still think the document was initially written to justify the use of Mode S for airlines, they have now stuck a bit on the front to force it onto GA under the guise of 'safety'.

SO the objective is stated in 2.1.1 The objective of this proposal is to make a significant contribution towards ensuring that the number of mid-air collisions and serious risk-bearing ‘near-miss’ incidents in UK airspace does not increase and, preferably, decreases as the level of air traffic grows and the issues they have identified are in 2.2.5 to 2.2.12 inclusive.

Issue 2 (2.2.6) is the only issue that appears to be relevant to GA. Force the airlines to carry mode S (already done) and the other important issues are solved. The other minor issues are fluff. For issue two, they are hanging their hat on reported Airprox figures. These are incredibly subjective, the vast majority are found on investigation to be no risk to fligt. We could manipulate the figures by putting a request on PPrune to either report anything or nothing for six months.

(a) Putting Mode S in spamcans will do nothing to alter GA on GA collision risk. You need some TCAS device to do this, and that is not mandated and I doubt it ever will be as the goal is simply to force all users to carry mode s. If this is forced through it will only be for the benefit of airlines who decide to enter class G so they save money, so those gaining the benefit (the airlines) should pay.

(b) Airspace infringements. Yep, worth discussing and everybody would like to see these reduced. I'd say most airspace infringements are due to complex and excessive airspace, the design of airspace in the SE is a complete mess.

They appear to accept my argument. 4.7.3 it is highly likely that the number of airspace infringements would increase above current levels if more UK airspace was converted into controlled or restricted access airspace. So a corresponding reduction in this controlled airspace should reduce the number of infringements. How to do this?

I go back to my Mode C veil. LHR is the only significantly large airport in the UK and a mode C veil would pretty much cover this and the satellite airports like LGW and LTN. Give LHR a 30 nm mode c veil, reduce surface area as aircraft would now be squaking altitude so ATC would indeed have decent knowledge of position and intentions. LGW, LTN, STN to have 5nm radius surface areas and there is a huge amount of airspace freed up for everybody. Choke points removed so airproxes down. Objective one satisfied. Draw a 30nm veil on the southern england chart and it doesn't really get in the way, people without transponders will have to fly around it, but that is a price one pays. The airlines/ATC/CAA will benefit most from reduction in infringements, so using the principle of the person who gains the most pays the most, they should pay.

It will never happen :)

(c) Regional airports. The figures tell the story, these are not very busy at all. 5 mile radius surface areas should be plenty. Works in the US with smaller surface areas. The recent airspace grab at Bristol shows the CAA have no intention of using mode S to reduce controlled airspace. They want Mode S and increased airspace, if mode S was going to introduce efficiencies they would not have done what they did at BRS.

(d) Gliders. Just another airspace user, to include them is BS fluff.

(e) TCAS in GA. Well, if we want it, let us pay for it. NO need to mandate - er it isn't, so why bring it up?

(f) MOD. Well, they aren't being made to do anything and probably wont, so why bring it up? BS.
Rest of the document is full of 'may', 'possibly', 'could'. All BS assumptions, better left out of a serious document which will cost GA tens of millions, but on speed reading it looks good and I guess that is what they are hoping will happen.

The cost part of the equation has been covered by others. Sounds like the CAA are BS there too, wouldn't surprise me reading the rest of the document.

They need to detail the alternatives they have rejected out of hand. ALso need to detail the alternatives threatened in 2.2.2

Haven't time to proof read this, just random thoughts and rantings. The CAA want to do it so they can see where we are, and not for safety reasons. The airlines may have a safety interest, but they really want to see us so they can cut corners and save money (or later charge us for using 'their' airspace), so if it goes through they should pay.

IO540
17th Aug 2006, 09:25
Presumably, replacing the LTMA with Class C airspace with Mode C type veils etc would mean a redesign of the SIDs and STARs. The LTMA shape, AIUI, is based around the present procedures.

This, I think, is why the ATC profession is dead against major airspace changes like that. They would have to change just about everything.

robin
17th Aug 2006, 09:54
Slim_slag

A fine response.

At a recent meeting BGA representatives highlighted the lack of any mention in the Partial RIA to H & S risk from a Mode S transponder in a rag and tube aircraft or when held on the person.

It now seems that the CAA are producing a separate analysis of the radiological issues, but this will be published in late Sept or Oct ie after the consultation has closed and therefore we will be unable to comment on the analysis

As you rightly mention the paper is shot full of holes, and has been cobbled together using questionable statistics. Even the response form is loaded so that the 'tick boxes' will support the CAA view

Note that if you tick the 'Do Nothing' option on Response 5, this does not mean that you support the idea of 'Do nothing' but that you support the view of the CAA in that 'Do Nothing' is unworkable.

They obviously know little about low-end aviation, and care less. Here is a classic quote from the RIA Section 5.2.5.1:

"For example, only those private pilots that use ATC would have their recreational flying directly helped by any economic benefits from more efficient ATS. However, they would benefit from ATC efficiency as members of the public when undertaking flights with commercial operators for business or pleasure."

In other words, for the financial outlay, we won't see any benefit unless we fly Chavair to Ibiza - nice one!!!

VP959
17th Aug 2006, 10:04
One thing that's clear on this thread, as elsewhere, is that a small minority of aircraft users are calling the shots.

Just for interest, here is the current % make up of the UK aircraft fleet, using the CAAs own data. Remember ALL are currently included in the Mode S proposal, unless it gets amended. I've listed them below in decreasing fleet size order:

Foot launched aircraft, powered and non-powered = 26%

Light single engine piston = 21%

Microlights = 15%

Gliders and SLMGs = 10%

Balloons and airships = 7%

Amateur built fixed wing = 6%

Helicopters and gyros = 6%

Commercial Air Transport = 4%

Light twin engine piston and larger singles = 2%

Vintage and historic = 2%

Turbine light aircraft = 1%

What is clear from this list is that a very large number of these aircraft are not using radio, are not using air traffic control facilities, are not flying anywhere except in class G airspace and are restricted to VFR flight only, yet these are the ones bearing the brunt of the financial impact of the mode S proposal.

VP

slim_slag
17th Aug 2006, 10:27
That's an excellent point robin. The CAA is also supposed to adhere to the 'user pays principle'. By their own admission, it's only the airlines who will be using the "new efficient" ATS who benefit, so the airline should pay. If the cost to equip the GA fleet is as little as the CAA claim, it shouldn't be too much of a problem for the airlines to pay for it. And they can look at it as a deductible investment towards future money saving efficiencies.

Of course why mention ATS efficiencies when the stated objectives are only safety based? It's a BS way to sneak through a financial burden on GA using a BS safety argument, the financial benefit of which accrues to the airlines. We can see who regulates the CAA.

zkdli
17th Aug 2006, 16:08
This is an interesting thread. SLim_slag when you talk about no TCAS for GA you seem to have forgotten SKYWATCH equipment that is in the SR22 etc. That is a traffic avoidance system that anyone lucky enough to be in a SR22 can use and that is based on SSR (mode s or c) I personally think that when ssr has been around for over 60 years in one form or another, perhaps we should be looking at it as away of enhancing safety. After all you wouldn't fly without using a seat belt, why would you want to fly with out something that could stop you being swallowed by a turbine engine or chopped by someones prop?
Stands back and watch the flames:O

IO540
17th Aug 2006, 16:27
Fair point; however the system you refer to costs about £10,000 to install, so few UK GA pilots will go for it.

Also there are very few GA-GA mid-airs, zero in IMC I believe (in the UK, so far), so the case for this is not strong. The traditional viewpoint in traditional UK GA is that you are supposed to keep a lookout (what the traditionalists call the "Mk 1 eyeball") in VMC, and those who are concerned about a mid-air in IMC can fly around in the knowledge that they are far more likely to hit a hill, so actually they would be better off spending similar money on GPWS.

Debating this, one just goes round and round. One could make a case for mandatory Mode C in the vicinity of busy controlled airspace (as they have in the USA), for reasons of traffic separation, i.e. to get a better grip on the numerous and rising CAS infringements. But at the same time PPLs are taught the same old dead reckoning navigation techniques and absolutely nobody (who is in a position to change anything) wants to do anything about that, so infringements will continue, regardless of what transponder equipment planes are carrying. If I was in charge of reducing infringements, I would first tear all my hair out, and then make Mode C mandatory around CAS, US-style.

Unfortunately the last thing Europe is going to do is what America does, on the principle that Europe always does it better....

ProfChrisReed
17th Aug 2006, 17:46
If this is true, then perhaps someone should explain to the Transport Minister, and to the Prime Ministers Office that the CAA are 'massaging the figures' (rather than a more confrontational term) to circumvent the Prime Ministers Office?

Annoyance coming from the Prime Ministers Office will get far more attention in the CAA offices, than annoyance coming from a load of GA pilots.

I have emailed the Cabinet Office, pointing them to this thread.

B Fraser
17th Aug 2006, 18:01
Say no to mode s Transponders!

I don't seriously believe that anyone in the CAA gives a toss about paragliders although the BHPA may have you think otherwise ;) Perhaps I should call up the local ATC for Radar information next time I go ridge soaring at 50 feet AGL with my buddies and stop looking over my shoulder.

slim_slag
18th Aug 2006, 08:00
zkdli, hope you don't think telling you "I never actually said that" is a flame :)

I am sure the number of reported airproxes would drop if all GA craft had some sort of optional TCAS connected to their mandated mode S transponder, but it would not drop to zero as Table 13 shows.

When the US was mandating Mode S for commercial operations, it looked at mandating mode S in GA flights, but decided not to do it. One of the concerns was 'saturation' of the 1090MHz frequency and swarms of GA planes filling all the displays on the ground and in the air. Any possible frequency saturation must be made considerably worse if GA planes are actively transmitting, which is what happens when you have TCAS on board.

Anyway, this issue is brought up in the Partial RIA, section 3.2.3 (e) The GA community has raised concerns that widespread equipage of SSR transponders on aircraft that routinely operate in large ‘clusters’ could saturate radars, ATC systems and ACAS.How has the CAA responded to what sounds like a genuine concern?The CAA has investigated this issue and conducted modelling for the period up to 2012, which indicates that there should be no significant problems in this regard2012? As far as 2012? WTF. That's four years after this is all due to start! What happens in 2013? Are they saying they don't know whether the system will be overloaded in 2013? Looks like it to me. What happens then? They say "Further modelling will be conducted", so publish the model and the results and let us comment on that too BEFORE they implement what appears to be an expensive experiment which if it works will only benefit the airlines and ATC.

This partial RIA is a joke, but seems like their mind is made up.

BEagle
18th Aug 2006, 08:38
Well, I think we should have a rethink about all the factors involved - and also take the opportunity to harmonise/simplify things generally. We'll have to give way to some extent, but Mode S transponders on paramotors would be just plan madness.

What about:

Class A to C airspace - Mode S compulsory.
Class D - Mode S compulsory under IFR if > 2000kg. Mode C compulsory under IFR and < 2000 kg, Mode A compulsory if under VFR and < 2000 kg.
Class E to G - Mode C compulsory under IFR. No transponder required under VFR.

And how about a 6000ft UK-wide TA whilst we're at it?

Tin hat on.....

IO540
18th Aug 2006, 08:47
I thought Mode S was already mandatory for all IFR.

Or it is just IFR in CAS?

People also forget that this is a Euro-wide thing. All very well to get an exemption in the UK but what is going to happen to popping over to France?

Rod1
18th Aug 2006, 09:50
IO540 is quite right about the Europe wide bit, 8000 French micros are already except and the home built sector are pushing hard for the same treatment. Agreements allow all the French aircraft into UK airspace for a certain number of days (60?) a year.

If you force non radio Aircraft to fit mode S how are you going to know if it is accurate in the air? My only airprox in many years and 800 hours was in IMC. I was tracking via a VOR on a RIS in the open FIR. I was warned of unknown traffic indicating 2000 feet. I was 1000 feet above so carried on. I was in and out of cloud but above a solid layer, I came out of one bank just in time to see an aircraft flash under me left to right very close indeed. RIS indicated it was the unknown traffic so his encoder must have been out by at least 800ft. In this case both aircraft had mode C, but only one was talking to the local LARS. My examiner (it was an IMC renewal) did not report the incident. Mode S would not have helped in this case, which is also the case in all the fatal mid air collisions that have happened in recent years.

Rod1

BEagle
18th Aug 2006, 10:05
Don't forget that much of Europe doesn't permit flight under IFR outside CAS in the first place!

We Brits do have some traditional rules which we must fight to hold on to in the face of mounting Eurocracy!

IO540
18th Aug 2006, 10:44
Don't forget that much of Europe doesn't permit flight under IFR outside CAS in the first place

The essential thing here is that by allowing IFR OCAS the UK acknowledges what is a fait accompli anyway i.e. nobody knows whether you are VMC or IMC when en-route, so no enforcement of any of the VFR rules (clear of cloud, a specified distance from cloud, a specified visibility, in sight of the surface, etc) is possible anyway.

Look at the huge growth of the high-end ultralight and permit categories. A lot of them very well equipped for what is obviously IFR operations. But of course none of these people ever go into a cloud ;)

Not being able to fly IFR OCAS simply means that one cannot request an instrument approach without drawing attention to oneself, in the "not having the JAA IR" department. And one gets stuck at towered airports if the cloudbase is below the VFR departure minima. Other than that, I am sure there is just as much "IFR OCAS" in the rest of Europe as here.

The UK rules go hand in hand with the IMC Rating, which as far as I can tell is close to unique in Europe. Also fairly unique is the anally retentive manner with which Class D is dealt with, being treated as Class B or C, so I think the present situation is just handy for the CAA which really doesn't want to change the airspace management.

tmmorris
18th Aug 2006, 10:53
Beags,

Seems eminently sensible, but I anticipate that ATCOs will want mode C in classes E-G where it underlies classes A-C (which is basically everywhere), to avoid having to call traffic (and spurious TCAS activations) on low-level VFR. Of course, one solution would be to mandate mode C for IFR and prohibit mode A only squawks for VFR - mode C or nothing...

Tim

BEagle
18th Aug 2006, 16:10
So that would be:

Class A to C airspace - Mode S compulsory.

Class D - Mode S compulsory under IFR if > 2000kg. Mode C compulsory under VFR or under IFR if < 2000 kg.

Class E to G - Mode C compulsory under IFR. No transponder required under VFR.

tmmorris
18th Aug 2006, 16:23
Yes, but it would be undermined if lots of VFR traffic squawked mode A only underneath CAS - would cause TCAS warnings (as far as I understand, TCAS being rather outside my experience...!)

Tim

IO540
18th Aug 2006, 17:57
Mode A is pretty useless. Especially if one takes the charitable view that the driver behind all this is CAS busts; Mode A doesn't help with busts from underneath.

In fact, if there was the slightest possibility of Mode C being acceptable (rather than S) upgrading a Mode A installation to Mode C is relatively cheap. One can pick up a Mode C on U.S. Ebay (or from various secondhand avionics shops) for a few hundred quid, and currently there are plenty around due to IFR pilots having to put in Mode S.

BEagle
18th Aug 2006, 19:07
OK then:

Class A to C airspace - Mode S compulsory.

Class D - Mode S compulsory under IFR if > 2000kg. Mode C compulsory under VFR or under IFR if < 2000 kg.

Class E to G - Mode C compulsory under IFR. Mode C optional under VFR, Mode A not permitted.

Would that be OK? - I'm meeting the CAA next week.

bar shaker
18th Aug 2006, 19:26
I thought Mode S was already mandatory for all IFR.
Or it is just IFR in CAS?
People also forget that this is a Euro-wide thing. All very well to get an exemption in the UK but what is going to happen to popping over to France?


Just tell them you are a Eurostar. The DGAC have exempted all 8500 French microlights.

tmmorris
18th Aug 2006, 19:45
Yes, that seems a good compromise, though I was happy with the status quo ante...

Good luck.

Tim

---

[per pretiosissima ad astra, these days]

Aunt Rimmer
18th Aug 2006, 22:09
Well, I still don't see why VFR in Class D should require Mode A, S or C.
At the moment Mode A/C is not mandated unless you are above FL100 and in Class A+B ( I think).
I operate out of a Class D airport, generally on VFR standard entry/exit lanes .... wait for it ..... WITHOUT A TRANSPONDER. :eek: The aircraft is placarded as VFR only anyway as it only has a Class 2 VOR.
Now, I know most of the ATCOs, I even trained some of them in a past life ;) , and despite the banter (ooh the banter :E ), I don't think my transponderlessness (copyright that one I think ;) ) has caused any problems whatsoever.
I still need ATC clearance, but sounding (and acting) like a sensible chap :8 and having a good relationship with my friendly ATC provider, they know I ain't going to :mad: them about.
Why should I have to have Mode S when for eg. French Eurostars or RAF Tornadoes apparently don't have to? The only difference in ops is that I'm a bit faster and carry 4 pob.:ugh:
Where is the logic ? :confused: Likewise, how is anyone going to know if the height readout is actually correct ? At the moment I have to verify the mode C of EVERY aircraft that I ident. How will anyone know if I have switched it off, or if it is u/s ? Particularly if I am operating out of a field outside CAS when I won't be speaking to anyone. Or even ... flying amongst the hills below radar and radio cover. Who will even see me ? or hear me ?
Once again it would seem that the over-crowded situation in the London area leads to faceless bureaucrats dictating kneejerk measures that are inappropriate outside the flatlands of the SouthEast. :=
I could go on .... and I will .....but the FM Immune farce was another case. Somebody elses commercial gain (radio stations), paid for by GA having to shelve out £2000 per radio for an upgrade. Same really as GA being squeezed out of regional airports for precious runway slots. Someone elses (RYR, EZY, FlyBe, BAW) commercial gain, GA gets the heave ho.
I thought part of the CAA Pension Funds remit was to support GA, not continually :mad: it over with extra costs and diktats. Oh silly me. :D
Anyway, Beagle, I respectfully amend your suggestion to <edit> also exempt VFR traffic operating in Class D from carrying Mode S, especially if they have a nice paintjob <end.edit>. :p
:E
PS Anyone planning on going to Barton next week for the CAA 'Open Consultation' ?

BEagle
18th Aug 2006, 22:47
You mean you don't want to fly under VFR in Class D? That seems a bit daft to me.

We need to give something, otherwise Mode S will be mandatory even under VFR in Class G.

Hence my suggestion.

I agree about the FM immunity nonsense - it cost us £17500 to sort out 4 x PA28s.... Yet in the USA with squillions of FM broadcasting stations, there is no such requirement.

Aunt Rimmer
18th Aug 2006, 23:08
Now, I am wading my way through the RIA document, with all it's shpeel about safety safety safety .....

Couple of things spring to mind. ....

CAA continually bang on about increased safety and wanting to reduce regulated airspace ..

So here's a couple of scenarios ....

Scenario 1
OK, I fit Mode S.

Johnny Tornado is exempt and doesn't have to - Johnny Tornado hammers around low-level, then zoom climbs through an advisory route from low level (pops up from below radar cover) causing men, women and children to be flung about in the back of an EZY737 (mode S and ACAS equipped) dropping into Inversneckie. Johnny Tornado (oblivious to the mayhem) then descends low level hammers round a couple of valleys and smacks into me (below radio and radar cover) just as I take off from Loch Tay.

Did Mode S make my flight safer ?
Did it make the 737s flight safer ?
Did it make the Tornadoes flight safer ?
Am I pissed off ?

Scenario 2
OK, I fit mode S. Johnny Tornado fits mode S and ACAS.
Same sortie - perhaps Johnny Tornado is now aware of the EZY737 ?
Perhaps JT is now aware of me coming round the corner ?
Perhaps we don't die, and save the £6m cost of loss of planes and life.
Then I can begin to see a benefit.

Scenario 3
Regional Airport near Glasgow with a large Class D Zone extending from surface all the way up to FL245. But IFR traffic into said airport cannit be descended under radar below 3000' unless within the final approach area. So, why not release that huge chunk of airspace below say 2500' outside of the final approach to VFR aircraft with Mode S ?

Scenario 4
The Highlands Restricted Area. Some of the most stunning landscape, (comprising about 50% of the area of the highlands), prohibited to light aircraft from 3pm, 4 days a week, because of military low flying (despite the fact that more low-flying actually goes on outside the HRA). This holds back any development of aircraft touring round Scotland.

But, if all military were to carry ACAS and Mode S, and if I was to too .... then why not open it up and allow free access .... ?

If I genuinely believed that this was not just some one way process to over control and over regulate for the sake of it, I would say yes.

But if the benefits are what the CAA say, then they should be willing to fund this for those benefits alone. The cost of a mid-air might be saved instantly.

Flying Lawyer
18th Aug 2006, 23:19
Report on a meeting held by the CAA on 15 August concerning the
“Proposal to amend the Air Navigation Order 2005 for the purpose of improving the technical interoperability of all aircraft in UK airspace”.

By Peter Saundby, Vice President, Royal Aero Club.
With advice from Tom Hardie, Peter Hearne and Ian Strachan.

This meeting was held in the Civil Aviation Authority, Kingsway, London, on Tuesday 15 August 2006. It was attended by some 28 persons, all the major Associations and AOPA being represented.

Tom Hardie who is tasked with the GA Alliance response was present together with Peter Hearne and Ian Strachan representing the BGA but equally concerned with other recreational aviation interests.

The meeting was chaired by Andy Knill, the CAA Manager for ‘Surveillance and Spectrum Management’ he has had a distinguished career in the development of secondary radar. He was supported by Andy Greenwood and Sqn Ldr Max Seaman, both of whom have professional backgrounds as fighter controllers in the RAF. The initial presentation was given by Gp Cpt Wragg RAF, but he then excused himself and left the meeting. His professional background is in air traffic control.
Therefore a problem was that none of this CAA ‘expert’ team has had any serious flying experience and, as I have written elsewhere, the sky looks different when seen from a cockpit rather than the radar room of a control centre.

From the BHPA and BGA points of view, it became apparent that the CAA team knew little about soaring operations. There is a need for the CAA to accept data that will be needed for the relevant modelling that yet has to take place.

An outstanding feature of the day was the repeated exposure of internal contradictions. On the CAA web site the meeting was described as “a workshop in support of the proposal to amend the ANO”. It was certainly not a workshop because nothing was produced and not one of the visiting attendees ever spoke in support of the proposal.

We opened with a presentation by Gp Cpt Wragg, in which he stated that this proposal was the culmination of fourteen years work, that the objective was flight safety and that the intention was to listen. It was a proposal and open to consultation. However the ‘experts’ had considered and rejected other options and this became only too clear later in the meeting. He also assured the meeting that there was no intention of using the information on traffic for other purposes, presumably referring to past suspicions of charges for airspace use. He was keen for responses although time will tell whether his team will actually take any notice of these.

Andy Greenwood then showed some initial responses to the consultation document, there had been 850 individual responses, 28 small businesses and 1 large business. 80% supported voluntary equipage and 77% did not believe that there would be any safety benefit. Of the replies from small businesses, 75% expected losses and 25% would cease trading. His argument was that the case for universal transponders was a safety case and even implied that those who opposed were against safety!
From the audience it was repeatedly put that the safety case was for electronic visibility and not mode ‘S’ transponders, these being merely one potential solution and also not the one being progressed by the Federal Aviation Administration in the USA.

Most of the CAA presentation was in support of the concept of electronic visibility, that this would reduce the risk of collisions, facilitate traffic management, enable traffic growth and replace current obsolete systems. All this is uncontroversial and agreed by those present. However the only technical solution ordained by the CAA is the carriage of mode ‘S’ transponders. Therefore the real debate as to whether this is the optimum or the only technical solution never took place, indeed the Chairman ruled discussion out of order saying “that it would take three days of meetings to address this issue”.

It is apparent, and was even admitted by the CAA team, that ADS-B [broadcasting of position by the aircraft] will become the system for the future and therefore the CAA advocates the purchase of transponders with extended squitter. Consequently the purchase of any other transponder can only be an interim measure. There appears to be a determination by the CAA to avoid any expenditure involved in the immediate modification of infrastructure to accept ADS-B information while appearing to discount expenditure imposed upon others.

In what discussion did take place, it was pointed out that TCAS suffers limitations when used for pilot controlled collision avoidance because there is no vector information and this had been the subject of a warning by Eurocontrol. A transponder needs to be illuminated by radar before responding and this may not always be the case at low level. The possibility that a very large increase in airborne mode ‘S’ transponders might result in spurious TCAS warnings was discounted by the CAA team. However it was pointed out that in the development of military systems it had been found unwise to rely solely on modelling and that flight test verification is essential before final decisions are taken.

Discussion of international issues exposed further contradictions. It was stated that ICAO had mandated transponders although this is not true for those un-powered aircraft included in the CAA proposal. At one moment we were being told that ICAO was mandatory, the second that the CAA were encouraging the development of low output transponders that did not meet the ICAO specification. Accounts of developments in France and Germany did not match with information from elsewhere. This CAA proposal runs counter to the declared aims of the EASA Board to encourage technical innovation and the development of light aviation in Europe.

A reference to UAVs was equally inconclusive. The CAA envisages widespread civil and military use and the electronic visibility of all other airspace users could enable an avoidance system. However the same arguments exist as to how that visibility could be created. An important point made was that questions power supply and weight are as equally critical for UAVs as for recreational aviation. The question of radiological protection was only raised at the end. This is related to output power, but thermal considerations alone were considered. Interference with cardiac pacemakers and non-approved aircraft electronic equipment has not been explored. Indeed a delusion exists in the CAA that with EASA airworthiness approval, all instrumentation in gliders will become certified.

Much faith is being put by the CAA in the development of low powered low cost transponders, LAST and LPST. Prices were cited as low as under £1000. However these items, despite past efforts, have not yet been developed and we now have a chicken and egg situation. A representative from the company implied that they could not justify ‘bringing to market’ costs unless that market was assured. That leads to the position that future legislation may ‘require’ the fitting of equipment that does not yet exist. The Chairman ignored strong pleas from those representing organisations that no specification should be issued without consultation with those who would be compelled to use the equipment in the air.

There was limited discussion on possible hybrid systems, squitter transmissions passing information on aircraft position and vector based on internal GPS navigational systems. This was rejected by the Chairman who clearly did not believe the integrity and accuracy of current commercial [off the shelf] GPS systems despite evidence being offered to the contrary.

The BHPA protested that the CAA had not consulted on actual air space usage and that must be taken into account by the CAA. This case was supported by the BGA because the same point has been made at earlier GACC meetings. The CAA team agreed that they would now be prepared to examine such material. The BGA made the further point that the proposed change in the regulations would involve a prohibition on the ability of gliders to fly IMC in unregulated airspace. This change would be resisted because it had no sensible connection with transponder carriage and was entirely contrary to the concept of electronic visibility.

Individual exemptions from the ANO will be permitted on various grounds, and blanket exemptions will be permitted for certain in-service military aircraft. However these exemptions must detract from the concept of universal visibility and may prove difficult for the CAA to administer.

In summary this was most unsatisfactory meeting, although that was not unexpected. It is not obvious what motives are driving our CAA. The overt reasons do not appear adequate to explain what will become a major political and perhaps legal battle. Maybe the adverse financial and economic implications for general aviation are not appreciated. Certainly the meeting exposed a lack of knowledge by these CAA ‘experts’ of how recreational aviation operates and this ignorance cannot be dispelled by a few visits to Clubs, but needs honest and open cooperation between the CAA and the relevant associations.

They must understand our operations and we need to know the pressures driving their policies. The major reason cited was flight safety and the collision risk, yet few fatalities arise from this cause and the same expenditure on other measures would save far more lives. Even the majority of respondents have not accepted this particular flight safety case. Is our CAA concerned that that their responsibility for airspace management entails legal liabilities? It was stated that the increase of controlled air traffic drove their proposal, but this increase is in controlled air space while the proposal relates to unregulated airspace.
Another reason given was that the CAA has already spent fourteen years and it was time to move on, but the logic of this is not obvious. International considerations were treated selectively and only those that supported the CAA case were cited. Despite statements to the contrary, the decision to amend ANO has apparently been made and will be driven through. Actions speak louder than words.

While all agree that electronic visibility is desirable, there are obvious alternative and much better technical solutions to those advocated by the CAA. The FAA is leading with ADS-B and in aviation the Americans force the pace. At best the CAA proposals can only be an expensive interim solution. Adoption of ADS-B could solve the CAA problems of costs, radio spectrum congestion and windmills. The statement by the Chairman that there would always be civil radar for air traffic control was without supporting evidence. As was demonstrated at the meeting, ADS-B can be small light and low powered. A complete navigational pack for para-gliders weighing only 180 gms was exhibited and this could feed a low power transmitter.

The reason for this impasse between general aviation and the CAA is difficult to discern. Their attachment to obsolescent systems is inexplicable because the CAA employs well qualified individuals who must be aware of modern developments. However a point not addressed at this meeting is that there are pressures on the CAA for the use of small regional airfields by commercial air traffic. As reported by GASCO, the Guild of Air Traffic Control Officers recently expressed their concern that the expansion of traffic has outstripped the capability of the Air Traffic Services. They have proposed a change from the VFR ‘see and avoid’ to a ‘sense and avoid’ based on TCAS. Can this be a clue to a covert reason for the present activity by the CAA?


"It was certainly not a workshop because nothing was produced."

I like that one. :ok:

Aunt Rimmer
18th Aug 2006, 23:48
both of whom have professional backgrounds as fighter controllers in the RAF

Well that IMHO says volumes.

It appears to me that the CAA is not being staffed by people with a working knowledge, sympathy or understanding of GA and small aeroplanes. Plenty of senior posts are now being occupied by ex-RAF FC's and ATC'rs who do not have the broad experience or civil licences associated with the areas they are now being asked to regulate. Nice cushy number - leave at 38/16 point with RAF pension straight into a nice desk job with lots of paperwork and a nice pension to boot ..... the difference is, in the RAF they might not be used to having their decisions challenged or scrutinised from below - however out in civvy street ... it is another matter .... I hope !! So get challenging !!

Professionally speaking, I have found FCs to have a stunning lack of understanding about civil ATC ops (never mind GA) - living in a darkened distorted world where everyone is a 'target' would lend itself nicely to the philosophy of overcontrol and over-surveillance that this RIA represents.

I'm sorry but I have no faith that their RAF experience is of any relevance to civil aviation and GA in particular. In fact the gung-ho 'they're all nobbers' attitude displayed by many ex-RAF CAA staffers to GA and PPLs is frankly depressing and a bloody disgrace - especially as it is these 'nobbers' who pay both their :mad:ing pensions.

I know there are a few exceptions, and yes I am generalising, but there are few dedicated flyers pissing into the CAA wind.

Ironically, FCs have been involved in two of my most recent airmisses. Ha ha ha. So here's a thought, why not make THEM fit a Mode S transponder ? I have applied for an EASA STC to show where they could be inserted ..... :eek:

Their (the CAA) attachment to obsolescent systems is inexplicable ... Perhaps it is just a product of a cold war mindset ?


I stand back and await the tirade .................... :D

IO540
19th Aug 2006, 08:55
Aunt Rimmer

they know I ain't going to :mad: them about.

Again taking the charitable position regarding the CAA's intentions (whether justified or not), the problem is that a large chunk of the product of the PPL training establishment do not fall in the same category...

Tudor Owen's post is pretty amazing but not suprising. A lot of people have been saying for years that the CAA is run by retired RAF navigators, who joined the CAA to preserve their pension rights, and back in the RAF they had no option other than a desk job (or no job) anyway. You only have to watch a certain CAA safety evening presenter to see the patronising attitude.

slim_slag
19th Aug 2006, 09:04
Well, FL, interesting post. They don't seem to know what the CAA are up to either.

When one reads some of the threads on here, then looks at AAIB reports, then looks back at threads on here, it seems that the airlines are doing what they want to and the CAA are a rubber stamp agency. I hate to be a conspiracy theorist, bu the only thing that really fits is the airlines deciding GA must use Mode S for their purposes, and the CAA are rubber stamping that decision too.

So if the people at that meeting are correct and this is going through no matter, is the only solution then a judicial review? Expensive stuff I would think. And I am sure judges doing these reviews are hyper-intelligent beings, I am sure they can be swayed by the regulator playing the safety card, and I bet that would be their gambit there too.

IO540
19th Aug 2006, 09:18
The cost of a JR is five figures and up.

The basis for it would be the failure to follow the statutory procedure, e.g. doing a proper consultation. Probably easy enough to show in this case.

B Fraser
19th Aug 2006, 10:04
A fascinating post FL, I was surprised to see that the Balloon fraternity were not represented by the BBAC.

Your average hot air machine is around 100,000 cubic feet of brightly coloured ripstop nylon above a highly visible "beacon" powered by LPG. All flights take place in reasonable to perfect visibility. Just how would a mode S transponder make a collision with a balloon less likely :confused: Perhaps the CAA think balloons are difficult to spot ?

http://img.photobucket.com/albums/v248/boxster986/Sloggi-Balloon-composite.jpg

The CAA - "We're not happy until you're not happy"

Pitts2112
19th Aug 2006, 10:28
The more I'm thinking about this whole thing the more I'm becoming convinced that the CAA are going to do what they want to do, that they have already made their minds up and that this consultation is really no more than a sham. So to who are the CAA reportable that will ensure they follow a genuine consultation and take the views of those about to be regulated into account? I know that's not a real strength of this government anyway, but it seems that involvement by the government is about the only way to hold the CAA accountable.

It seems to me that MP involvement is the next stage. I've already mentioned this issue in an e-mail to my local MP and will be following up with a phone call next week. I'm not sure what he can do directly, but if he can point me in another direction, or ask a few key questions within the DfT, then maybe a little MP attention on the matter may help the CAA see there is another way to handle this.

The thing that's really frustrating is that, as a community, we're not unwilling to be regulated. We just seem to have very little say in how it happens. Having said that, the PFA, BGA, BMAA have quite a lot of devolved authority, so the idea is not completely foreign to them. Maybe that's something we can build on. At any rate, if a few MPs ask the questions, then it becomes an issue the CAA and DfT can't just sweep under the carpet.

Just my further .02 worth.

Pitts2112

robin
19th Aug 2006, 19:27
Well, FL, interesting post. They don't seem to know what the CAA are up to either.
When one reads some of the threads on here, then looks at AAIB reports, then looks back at threads on here, it seems that the airlines are doing what they want to and the CAA are a rubber stamp agency. I hate to be a conspiracy theorist, bu the only thing that really fits is the airlines deciding GA must use Mode S for their purposes, and the CAA are rubber stamping that decision too.
So if the people at that meeting are correct and this is going through no matter, is the only solution then a judicial review? Expensive stuff I would think. And I am sure judges doing these reviews are hyper-intelligent beings, I am sure they can be swayed by the regulator playing the safety card, and I bet that would be their gambit there too.


Just back from FFF at Kemble, where I had the joy of talking to a member of the CAA who worked on the TCAS proposals.

When I mentioned the example of the collision quoted in the RIA as justifiying the mandating of Mode S he was horrified, as he has not seen an example of an incident reported through AAIB yet where Mode S would have made any difference. He promised to read through the document and look at the proposals where TCAS is quoted.

So if the CAA don't even talk to each other.....!!!!

QDMQDMQDM
19th Aug 2006, 20:11
A lot of people have been saying for years that the CAA is run by retired RAF navigators, who joined the CAA to preserve their pension rights, and back in the RAF they had no option other than a desk job (or no job) anyway. You only have to watch a certain CAA safety evening presenter to see the patronising attitude.

I couldn't believe it when I went to one. I am guessing it is the same bloke. He came to Devon to talk to a bunch of rag and tube aviators and he had absolutely no idea whatsoever about the world we operate in and, even worse, he didn't appear to give a toss about that fact either.

The Mode S thing is preposterous -- unelected officials gone berserk. Ask a bureaucrat and the answer is always more asinine regulation, whatever the question is.

Regulate first, think later, if at all.

QDM

IO540
19th Aug 2006, 20:44
Same man probably. The name escapes me.

I went to one of these a while ago. I asked him something about IFR, somebody in the audience hissed "you don't need IFR, you can go everywhere VFR" and he seemed happy with that. Then somebody (don't think it was me, but it could have been) mentioned the 3-letter dirty word ("G" "P" "S") and the audience started turning around and shaking their heads in disapproval... Much of the audience are a bunch of "groupies" who go there to get their logbooks stamped. I suppose, to be charitable, these things are aimed at very low hour pilots, which make up much of the UK PPL scene and probably much of the incident data.

So what we have here is one little bit of the CAA which is astonishingly backward, stuck in the goode olde world of WW2.

But we also have a very modern CAA, with intelligent people (e.g. some IR examiners) who know what GPS is, can even program a route into a GNS530, to whom for example BRNAV (which - triple INS equipped transport jets aside - is impractical outside the IFR approved GPS context) is everyday stuff, and who cannot possibly have these backward attitudes.

Then there is the bulk of the CAA which looks after jet transports and they are obviously pretty smart.

My own experience of dealing with the CAA is that the organisation contains a lot of very able individuals.

What amazes me is how these "factions" can co-exist in the same building, never mind generate any sort of coherent policy.

Flying Lawyer
20th Aug 2006, 18:51
B Fraser

The BBAC was represented through the Royal Aero Club, the national co-ordinating body for recreational flying in the UK. The national associations of all the principal air sports in the UK and are represented on the RAeC Council and Committees, including -
British Aerobatic Association
British Balloon & Airship Club
British Gliding Association
British Hang Gliding & Paragliding Association
British Microlight Aircraft Association
British Model Flying Association
British Parachute Association
British Precision Pilots Association
Formula Air Racing Association
Helicopter Club of Great Britain
Popular Flying Association
RAeC Records Racing & Rally Association
Historic Aircraft Association
PPL/IR Europe
Tiger Club

The RAeC is also the UK representative on Europe Air Sports, the body which co-ordinates responses to legislation and regulation affecting recreational flying within the EU and more widely throughout Europe.
The President of EAS, Sir John Allison, is a former RAF officer but (thankfully) he certainly isn’t the sort of RAF type described in some posts above.
He was a fighter pilot who retired as Air Chief Marshal of the Royal Air Force and Commander-in-Chief of Strike Command, but he’s no desk-pilot - he's one of us. Although best known for displaying Duxford warbirds and as a Shuttleworth pilot, he's always been and still is an active light aircraft owner/pilot.
An extract from a speech illustrates the marked difference between his approach and some others mentioned: The recreational and sport pilots in powered aircraft, glider and hang glider pilots, the microlighters, the home-builders, the balloonists, the parachutists and the aero-modellers …………. are all too easily overlooked when the legislator reaches for his pen.
It is for all these sporting and recreational pilots and aviators that I take the opportunity to speak.

………. Too often it is forgotten that at the receiving end of all legislative changes are the hapless citizens real people leading real lives who have little interest in politics. They will accept reasonable, proportionate and necessary change, but otherwise they just want to get on and enjoy their recreation without undue interference. I am one of those.

Having regard to the large numbers of these ordinary citizens affected by changes to the aviation environment in Europe, I would caution legislators and politicians concerning the social and political health of the evolving European Union. Until recently, the citizens of Europe had experience only of the impact of national law on their pursuit of flying for sport and leisure. On the whole that experience was satisfactory. Nobody was unreasonably excluded by reason of disproportionate cost, excessive rules or by denial of access to airspace. However, almost all the changes, either already implemented or now in the pipeline, are adverse for the recreational pilot.

If new rules introduced by the institutions of the Union change the lives of its citizens for the worse, it can be no surprise if resistance to the entire European project is the outcome. I believe that is what is happening in my own country.

It is not persuasive to deploy the mantra of free movement across Europe as the primary justification. Many - especially the huge numbers who have no interest in flying far from their home airfield - would consider the price they are being invited to pay either in monetary terms or in reduction of freedoms is too high.

………. It is difficult to understand why, for recreational aircraft, we cannot just accept the existing airworthiness, maintenance and licensing regimes of all member states. These systems are already delivering an excellent level of third party safety so why move away from them?

I declare a bias because he's been a friend for many years, but IMHO he's just the sort of man we need fighting our corner of aviation.

slim_slag
21st Aug 2006, 08:22
So blame the Europeans, eh? Easy to do and popular with the masses. Problem with that is the RIA doesn't say Europe is behind this, in fact it says European regulations are nothing to do with this at all. Section 2.2.7 (c) talks about the Single European Skies initiative. sorry to quote it all, my bolding.

Under the SES initiative, mandates are being issued to EUROCONTROL by the European Commission to develop interoperability implementing rules on SSR Mode S Interrogator Code Allocation for radars and on Surveillance Performance requirements. However, these will not legislate for the carriage and operation of SSR transponders on aircraft, and appropriate mandates in this regard are not currently being muted. The SES initiative is still somewhat embryonic and the work programme has to be prioritised within available resources. Indeed, the initial SES rules are likely to just support existing programmes and projects. The UK policy proposal contained within this Regulatory Impact Assessment (RIA) is, therefore, complementary to foreseen future SES requirements for SSR transponder carriage. In any case, mandating the carriage and operation of SSR Mode S in UK airspace from 31 March 2008, ahead of any potential European legislation, is essential because of national concerns. These concerns are elaborated throughout this RIA but centre on the need to introduce measures that sustain or improve levels of safety in a joint and integrated UK airspace, while managing the increasing complexity of this airspace and the increasing density of air traffic using it.

Was going through this, and really should have bolded the whole lot. According to the CAA document, the "Europeans" have nothing to do with mandating the carriage of Mode S whatsoever. Sorry, but it appears the driving force behind this is coming from elsewhere.

Lucy Lastic
21st Aug 2006, 08:52
It sure is.

Looks to me as though the CAA hoped to have slipped this one in under everyone's radar, so to speak.

Unfortunately for them, like a 4 year-old caught fiddling, they are denying everything ("it wasn't me, mummy") and are trying to put the blame everywhere, except where it belongs.

And again, like a 4 year-old, it has no plans to change its mind on what it originally planned to do. Given that around 80% of respondents what voluntary equipage, that a significant proportion of businesses expect difficulty in funding the change and that even if Mode S were to be fitted to all GA, we'd still have collision risk from FJ traffic, there should be grounds for optimism

However, given the CAA's notorious lack of good faith, I'd not be surprised to see them steam-roller this one through - agfter all, this is only a consultation and not a negotiation

Consultation= ask your stakeholders because you have to do so, by law. Then make a few minor tweaks and carry on with what you intended

Negotiation= sit in a smoke-filled room for months with your stake-holders work hard, 'engage' with all sides and come up with a compromise solution broadly acceptable to all (or not)

Flying Lawyer
21st Aug 2006, 09:25
s_s

I wasn't blaming the Europeans for this.
I quoted the extract only to illustrate that some former RAF officers are on our side and fighting for us.
The speech refers to Europe because that's EAS area of responsibility. It was given at EuroControl headquarters in Brussels.

Single Spey
21st Aug 2006, 09:55
Folks

I think we are all missing something fundamental here. The RIA is 'to improve the technical interoperability of ALL aircraft in UK airspace.' Has the CAA actually proven the case for ALL aircraft to have technical interoperability?

If there is a requirement to improve safety, particularly for ops outside regulated airspace, then where is the consultation and evidence to show that improved technical interoperatbility for ALL aircraft is the solution? What other options were considered?

I could suggest that one option would be to legislate that commercial flights above 5700kg (or whatever) may only take place into airports that have a radar approach service. In principle this is no different to legislating that these airports must have the required fire cover and be licenced. It could be made a condition of licencing. In this way there would be improved safety for commercial ops into airports in unregulated airspace without affecting the status quo for other airspace users in the vicinity. The commercial operator would pay for this through the airport fees, passed on to the customer who after all is the main beneficiary of the improved safety, and would find it hard to refuse if the argument is safety based.

OK, so what about microlights and gliders that might not show up on the primary radar and are not equipped with SSR? Well, two top of the head solutions: mandate that the radar equipment must have a performance capable of detecting low radar cross section targets, or encourage owners of low radar cross section aircraft have to be fitted with a radar reflector that increases the probability of detection.

The CAA appears to have leapt straight into trying to justify a technical solution, mainly on the basis that i) they need to clean up the RF spectrum thus conventional transponders are out and ii) commercial operators want to make more use of TCAS in unregulated airspace.
So let's see the evidence that supports 'technical interoperability for ALL'
and if it hasn't been produced let's push to postpone the current RIA and get the CAA to undertake the proper study to address the problem.

As an aside, earlier posts referred to the past military career of two individuals involved in the RIA process. I assume that everyone knows Andy Knill's previos military background? ;)

slim_slag
21st Aug 2006, 09:56
Well FL, the speech you quoted speaks for itself. It is riddled with references to regulation from Europe being bad, regulation from the member state being good. However all the evidence shows this idea is coming from the CAA or somebody using the CAA, and not Europe. So if your mate wants to be effective he should look into that and find out what is really driving this, and work out something that suits everybody.

Lucy Lastic
21st Aug 2006, 13:28
Folks

I assume that everyone knows Andy Knill's previos military background? ;)

Who? and what was it?

Sedbergh
21st Aug 2006, 13:35
There is a post on the Vintage Glider Club website forum dated August 18th which I will take the liberty of quoting.
"I went to last night's meeting with the CAA organised by Lasham (gliding club). It was very informative with a great deal of information passed in both directions.
It was very apparent that the CAA people didn't understand private GA let alone the gliding movement. However they were very open about taking on board the information that was proferred.
I have no idea what the outcome will be however I am sure that they are now fully aware of, not only the feeling raised by this issue, but also the illogic of their proposals when applied to the private end of GA.
My thanks go to Lasham and Patrick Naegli/Pete Stratten for the well organised very informative and well orchestrated event"
End of quote.

Jumbo Driver
21st Aug 2006, 17:30
OK then:
Class A to C airspace - Mode S compulsory.
Class D - Mode S compulsory under IFR if > 2000kg. Mode C compulsory under VFR or under IFR if < 2000 kg.
Class E to G - Mode C compulsory under IFR. Mode C optional under VFR, Mode A not permitted.
Would that be OK? - I'm meeting the CAA next week.

BEagle, I tend to agree with you on this, except I don't think Transponders should be compulsory under VFR in Class D. However, if they are carried and used under VFR in Class D, then I believe they should be Mode C, with Mode A only not permitted.

So, for me, it would read:

Class A to C airspace - Mode S compulsory.
Class D - Mode S compulsory under IFR if > 2000kg. Mode C compulsory under IFR if < 2000 kg. Mode C optional under VFR if < 2000 kg, Mode A not permitted.
Class E to G - Mode C compulsory under IFR. Mode C optional under VFR, Mode A not permitted.



...
Scenario 1
OK, I fit Mode S.
Johnny Tornado is exempt and doesn't have to - Johnny Tornado hammers around low-level, then zoom climbs through an advisory route from low level (pops up from below radar cover) causing men, women and children to be flung about in the back of an EZY737 (mode S and ACAS equipped) dropping into Inversneckie. Johnny Tornado (oblivious to the mayhem) then descends low level hammers round a couple of valleys and smacks into me (below radio and radar cover) just as I take off from Loch Tay.
Did Mode S make my flight safer ?
Did it make the 737s flight safer ?
Did it make the Tornadoes flight safer ?
Am I pissed off ?
...
Scenario 2
OK, I fit mode S. Johnny Tornado fits mode S and ACAS.
Same sortie - perhaps Johnny Tornado is now aware of the EZY737 ?
Perhaps JT is now aware of me coming round the corner ?
Perhaps we don't die, and save the £6m cost of loss of planes and life.
Then I can begin to see a benefit.
...


Aunt Rimmer, I understand your arguments about the benefits from ACAS but I think you (and some others on this thread) are overlooking one thing. It is not necessary to fit Mode S to provide the necessary response for Johnny Tornado's ACAS to see and avoid you with an ACAS RA. It is only Mode C that is needed - so you only need to fit Mode C to enjoy the benefits you describe above in Scenario 2. As I understand it, there is no enhancement to another aircraft's ACAS RA from you carrying Mode S, rather than Mode C.

Mode S is a totally unnecessary addition for most GA aircraft as they are not capable of providing the additional Air Data feeds such as TAS, heading, or datalink capability that Mode S can utilise. For such aircraft, the only "benefit" that I can see is that the aircraft identification is provided to ATC in the SSR response.


JD

Single Spey
21st Aug 2006, 17:39
What is worrying in this scenario is why should I need any transponder (Mode C or otherwise) under IFR in unregulated airspace - after all I can fly IFR in VMC and still provide my own separation.

The IFR outside controlled airspace - Minimum ht Rule 29, and quadrantals Rule 30. So how does a transponder help?

BEagle
21st Aug 2006, 19:05
Because it is people who are demanding IFR separation in 'free airspace' who are causing the whole issue. And why on earth do people fly 'under IFR' by day in VMC in 'free airspace'? What's the point?

In fact, if you were really stupid, you could also fly in IMC outside controlled airspace in the UK without any radar service (or even 2-way RT) and still be legal.... Time that such nonsense was stopped.

Give a little - or lose the lot. That's as I see it.

Height encoding transponders should be mandatory in Class D airspace - with Mode C being acceptable if < 2000 kg MTOW.

Mode A should be phased out everywhere asap.

tmmorris
21st Aug 2006, 19:20
In fact, if you were really stupid, you could also fly in IMC outside controlled airspace in the UK without any radar service (or even 2-way RT) and still be legal.... Time that such nonsense was stopped.

Quite agree - but not before there is 100% guaranteed radar cover above MSA, or at least at some sensible altitude. What are we supposed to do at the weekends, or after tea-and-medals-o'clock, for instance, when the RAF shuts down?

Tim

Single Spey
21st Aug 2006, 20:40
BEagle

I agree with tmmorris that until we get 100% radar cover above MSA then you can be forced to fly IMC outside controlled airspace without a service. So would you prefer us to all stay on the ground in those circumstances?

Regarding the people demanding IFR separation in free airspace - there is no such thing. There is no difference between separation in VFR or IFR it is only who is providing the separation that counts. And lets remember that TCAS which is what they wish to use to give them separation is not a separation system. It is a collision avoidance system. Any aircrew who use it for separation are misusing the kit, do not understand the limitations, and in some documented situations have actually eroded separation by using the TCAS display to try and vector around othr traffic. Are you now going to campaign to stop flights into airports without radar like Wick, Inverness under IFR, or more correctly in IMC, as you consider the operators to be really stupid?

The 'give a little or lose the lot' should be applied to the commercial operators and the answer as I have suggested is to legislate that they cannot operate commercial flights into airports without the appropriate infrsatructure which must include radar. NATS should be mandated to provide cover within the UK FIR overland down to 10000 ft. Then we have seamless cover for all IFR flights to operate with a radar service, thereby assuring separation and improving safety. This is the issue that the RIA attempts to solve. I still don't believe that the CAA have proved the case for ALL aircraft to be technically interoperable as the only cost effective solution.

Not sure what you see as the difference between a height encoding transponder and Mode C? In future you wont be able to even fit a Mode C transponder because they create too much RF pollution. The CAA would require it to be a Mode S ' height only' transponder as the CAA want to do away with Mode A and C No one that I am aware of makes a height only transponder that operates according to Mode S principles so cost of development and certification etc would be an issue. And then we have the problem that with a Mode C or height only return how would a controller know if it was verified or not without being able to see an associated callsign or recognised Mode A code?

IO540
21st Aug 2006, 21:11
In fact, if you were really stupid, you could also fly in IMC outside controlled airspace in the UK without any radar service

I am very suprised you wrote that, Beagle.

The alleged "stupidity" of it is not supported by any evidence whatsoever (midairs in IMC).

Anyway, what would you do to "fix" this dreadful deficiency?

First, you would need radar cover everywhere. CAS alone offers partial protection only, since anybody can still fly through it. In the UK, there is no radar service below the airways - other than bits of LARS when you can get it.

Alternatively, you would need to do what they do in the rest of Europe: restrict IFR to ATS routes (through practice if not fully through legislation), and require a full IR for any IFR. Then you end up with close to zero GA activity beyond little local bimbles. That's about what GA in most of Europe is: little bits of local flying. Anybody wanting to go places will just fly VFR in clouds if necessary. If you fly all the way from the UK to the far end(s) of Europe, you will see/hear more GA planes between Goodwood and Lydd than between the rest of the UK and say Egypt. This is what brainless regulation does.

One has to give the CAA credit for creating and maintaining (albeit starting from a point many years ago; it would not happen today) the present UK GA freedom which is very considerable. The UK IMC Rating is a super privilege too.

I agree with IFR in VMC being on the face of it rather pointless but you only have to call yourself "IFR" anyway should you encounter a little cloud, so I can't see any harm in it.

BEagle
21st Aug 2006, 21:36
"There is no difference between separation in VFR or IFR it is only who is providing the separation that counts."

OK - in that case take 'IFR separation' to mean 'separation from all other aircraft to the same extent as is currently available from RAS- irrespective of flight conditions or Class of airspace. 3nm between identified aircraft or 5nm from unindentified aircraft unless the height difference is known to be > 1000 ft '. To achieve that, all aircraft would need height encoding transponders. It would make little sense for anyone who doesn't yet have a Mode C transponder to fit one - but it would equally make no sense to require that perfectly good existing Mode C transponders in GA aircraft are thrown away.

Only a complete idiot would fly in IMC outside controlled airspace without a radar service - I remain resolutely convinced of that. Hence 100% 24/7 radar cover above MSA would be required to provide adequate safety for such activity. The suicidal pilot choosing to rely on the non-radar big sky theory won't be a threat to a TCAS-equipped airliner if his aircraft is fitted with a height encoding transponder - but he will be a threat to his similarly daft brother coming the other way who doesnt have TCAS.

IO540 - do you really fly in IMC outside controlled airspace without a RIS or RAS?

mm_flynn
21st Aug 2006, 22:38
IO540 - do you [i]really fly in IMC outside controlled airspace without a RIS or RAS?


There is not a lot of choice when the last thing you heard on the radio was 'squawk 7000, radar service terminated, contact on route frequency' and you are solid IMC and it is Saturday late afternoon.

Easy,easy,steady.
22nd Aug 2006, 00:36
I am military aircrew and also fly a hang glider and have some questions regarding the enforced use of mode s transponders from my own perspective.

1. What are the dangers of operating a microwave transmitter of unknown power output in very close proximity to me? I ask this as the I-band transponder fitted to the A/C at work has a 1.5 metre RadHaz around it.

2. How robust is the equipment going to be? As a member of the HG/PG community, our equipment is quite likely to get knocked around from less than perfect landings and take offs, and if it is rendered u/s as a result, will this not be an increased flight safety hazard by relying on kit that actually isn't working?

3. What use will I actually get from it? I don't use A to G radio (and don't have to) and can't carry a radar, so how will I know who's around? Admittedly it will alert ATC to my presence at known HG/PG sites as that is where we mostly fly but surely other A/C will have planned their Nav route beforehand?

4. Who's going to pay? The cost of the unit, annual maintenance, CAA licensing, etc all adds up to rather a lot of money and probably more than my glider!

5. How big and heavy will it be and what power will it require? I don't think this needs much in the way of explanation for HG's and PG's......

6. Regarding point 1 above, I presume the CAA will have a Duty of Care to ensure that the equipment that they specify will be safe to use, as i can imagine the number of lawsuits a few years down the line if we all start firing blanks or develop tumours as a result of enforced use.

This is far from exhaustive but just some food for thought. I must admit that I did find the questionnaire somewhat steered to what the CAA wanted to hear, and as for the time span before proposed implementation, well........................................:ugh:

Single Spey
22nd Aug 2006, 06:01
Quote by BEagle:

"The suicidal pilot choosing to rely on the non-radar big sky theory won't be a threat to a TCAS-equipped airliner if his aircraft is fitted with a height encoding transponder - but he will be a threat to his similarly daft brother coming the other way who doesnt have TCAS."

Two points. Under IMC both aircraft should be IFR and thus on quadrantals - so he will miss his brother coming the other way by 1000 ft. The only aircraft at the same level will be on tracks in the same quadrant.
I don't believe that TCAS can provide resolution advisories based on height only - it will identify the other aircraft but unless both parties have TCAS they cannot form a contract to agree avoiding action. And pilot must not use TCAS for separation purposes.

IO540
22nd Aug 2006, 07:05
IO540 - do you really fly in IMC outside controlled airspace without a RIS or RAS?

Of course, do so absolutely routinely. Same as most instrument pilots do. This is normal life in UK GA.

Let's say one plans an OCAS route, and along the route one might get a service from 3 LARS units. (In the UK one won't get a service from the IFR sectors e.g. London Control).

Perhaps one of the LARS units is shut, or is offering FIS only. There is me sitting in IMC. What do I do?

GA versions of TCAS (the proper ones, anyway, costing £8k+) give bearings to the targets. But until Mode C is mandatory, this equipment will be of limited use.

Quadrantals don't really come into it if low down say below the LTMA.

Obviously one tries to get an RIS but not getting it is not a flight planning issue like icing, conditions at the destination, embedded CBs, etc.

BEagle
22nd Aug 2006, 07:13
The idea of TCAS is to prevent collisions with people who should't be where they are. In other words, in an ideal world it would be unnecessary - originally proposed for use in terminal areas, its use has slowly been rolled to to en-route airspace as well.

TCAS will indeed provide Resolution Advisories against Mode C; however, if both aircraft have Mode S and TCAS II, such RAs will be co-ordinated.

If TCAS is used outside CAS, VFR traffic squawking Mode C may cause RAs to be generated because the degree of separation TCAS attempts to achieve is greater than the VFR 'see and avoid' separation being used. Crews should consider selecting TA instead of TA/RA in such an environment; they must not develop a culture of ignoring RAs.

With mandatory Mode S outside CAS, the incidence of nuisance RAs generated will increase due to the greater number of transponding aircraft around.

Mode A will generate TAs, never RAs. It thus becomes worse than useless - is the TCAS TA spurious because the Mode A aircraft is well clear of the other's level? Or does it mask a serious collision risk which would have generated a RA had the Mode A aircraft been equipped with Mode C?

As has been alluded to, TCAS must not be used for lateral separation due to the angular resolution being very approximate.

Flight in IMC outside CAS without a Radar Service is exceptionally hazardous. It is probably because you are one of the few people doing so that you haven't had a collision yet, IO540. What do you do if you can't obtain a radar service? Plan to fly in VFR or fly under IFR inside CAS. Or wait until the UK has a decent radar service outside CAS - which you will probably have to pay en-route IFR charges for.

'Low down' such as below the LTMA? Let's say that you take-off from somewhere like Elstree and there's an overcast cloudbase at 1000 ft. Are you really saying that you would fly in IMC below the LTMA without a radar service in such conditions? If so, at what altitude?

slim_slag
22nd Aug 2006, 07:35
With mandatory Mode S outside CAS, the incidence of nuisance RAs generated will increase due to the greater number of transponding aircraft aroundExactly. And the only logical result of that can be airlines demanding more controlled airspace, and the CAA rolling over and saying "how much". The partial RIA accepts this will cause an increase airproxes and airspace busts which runs counter to their claimed objectives, which is safety,

bookworm
22nd Aug 2006, 08:09
The idea of TCAS is to prevent collisions with people who should't be where they are. In other words, in an ideal world it would be unnecessary - originally proposed for use in terminal areas, its use has slowly been rolled to to en-route airspace as well.

I think that's a misconception. TCAS was designed with class E airspace in mind, particularly in the US, where VFR flights can quite legitimately share the airspace with IFR flights. Even in VMC, collision avoidance is difficult for the pilots of IFR aircraft which typically have higher closing speeds and sometimes higher workloads. History has demonstrated that see-and-avoid frequently fails, not through gross negligence but simply because of human performance limitations.

With mandatory Mode S outside CAS, the incidence of nuisance RAs generated will increase due to the greater number of transponding aircraft around.

So what you mean is that pilots of TCAS-equipped aircraft will now be given collision avoidance instructions for against others potentially on a collision course with them, where previously they wouldn't have seen them at all?

IO540
22nd Aug 2006, 08:26
This is off topic but I will answer it.

Flight in IMC outside CAS without a Radar Service is exceptionally hazardous. It is probably because you are one of the few people doing so that you haven't had a collision yet, IO540

Can you provide supporting evidence for this, Beagle?

Lucy Lastic
22nd Aug 2006, 08:38
1. What are the dangers of operating a microwave transmitter of unknown power output in very close proximity to me? I ask this as the I-band transponder fitted to the A/C at work has a 1.5 metre RadHaz around it.

Unknown as yet. The CAA forgot to include this in the RIA and have commissioned a study to report in late Sept - after the consultation period. Some EU states will not accept the use of 70W equipment in rag-and-tube aircraft

2. How robust is the equipment going to be? As a member of the HG/PG community, our equipment is quite likely to get knocked around from less than perfect landings and take offs, and if it is rendered u/s as a result, will this not be an increased flight safety hazard by relying on kit that actually isn't working?

You won't be allowed to take off without an operational Mode S.And this risk of failure will be worsened if they come up with the portable option. These can be dropped, kicked or stolen

3. What use will I actually get from it? I don't use A to G radio (and don't have to) and can't carry a radar, so how will I know who's around? Admittedly it will alert ATC to my presence at known HG/PG sites as that is where we mostly fly but surely other A/C will have planned their Nav route beforehand?

Good point, but then you probably won't show up on an ATC screen - they 'dial you out' or you'll be so low, you'll be under their cover. The benefit will accrue to the commercial airlines routing through the open airspace and using TCAS to avoid you - bad idea, but the accountants love it.

4. Who's going to pay? The cost of the unit, annual maintenance, CAA licensing, etc all adds up to rather a lot of money and probably more than my glider!

Simple - you will and yes it is a lot of money, probably no change out of £3k with annual expenses around £400. And it will form part of your annual maintenance check

5. How big and heavy will it be and what power will it require? I don't think this needs much in the way of explanation for HG's and PG's......

More power than you've probably got available to power an icom radio and GPS as well. It will certainly be too heavy for some very light aircraft

6. Regarding point 1 above, I presume the CAA will have a Duty of Care to ensure that the equipment that they specify will be safe to use, as i can imagine the number of lawsuits a few years down the line if we all start firing blanks or develop tumours as a result of enforced use.

They are not specifying it, and will fall back on the 'international requirement' defence. The joke is that in the RIA they are sating that they are taking a leading role in the development of a LPST, but no-one can see where this is happening. Ask them to justify the costs etc and they say this is a matter for the market

This is far from exhaustive but just some food for thought. I must admit that I did find the questionnaire somewhat steered to what the CAA wanted to hear, and as for the time span before proposed implementation, well........................................:ugh:

You've only got a week, so put your comments in

BEagle
22nd Aug 2006, 08:40
IO540 - if you can't understand that flying 'blind' without knowing what else is around is dangerous, then I query your airmanship and judgement. You don't need 'supporting evidence' to support what something which is fundamentally axiomatic. Rely on statistics and you may well become one yourself.

The 'quadrantal' argument is irrelevant - there may well be another suicidal fool in the same quadrant on a converging course with you.

And your answer to my Elstree question is...

Lucy Lastic
22nd Aug 2006, 08:48
Well said BEagle

I often use the nasty little airspace between WW and Elstree on my way north-east

In those sectors, and others, you can forget about quadrantals. Aircraft are making their way around the TMA, squeezed into a small area and keeping below the TMA, as best they can

So being equipped with TCAS with Wycombe gliders, circuit traffic, helos and transitting traffic, do you honestly know how to plot a course to avoid the traffic? You might avoid one to place yourself into conflict with another.

Aunt Rimmer
22nd Aug 2006, 08:56
Aunt Rimmer[/B], I understand your arguments about the benefits from ACAS but I think you (and some others on this thread) are overlooking one thing. It is not necessary to fit Mode S to provide the necessary response for Johnny Tornado's ACAS to see and avoid you with an ACAS RA. It is only Mode C that is needed - so you only need to fit Mode C to enjoy the benefits you describe above in Scenario 2. As I understand it, there is no enhancement to another aircraft's ACAS RA from you carrying Mode S, rather than Mode C.
Mode S is a totally unnecessary addition for most GA aircraft as they are not capable of providing the additional Air Data feeds such as TAS, heading, or datalink capability that Mode S can utilise. For such aircraft, the only "benefit" that I can see is that the aircraft identification is provided to ATC in the SSR response.
JD
I agree Mode C is all that is required - I was using Mode S as the example because
a) I don't have Mode A/C at the moment so IF I have to install a piece of kit under legislative duress it will be Mode S.
b) all the CAA talk/spin is about Mode S, so I think it better to use that as a counter.
But, yes, you are right.
One other thought - how is anyone (in the air or on the ground) going to know if the altitude info displayed by Mode S (or Mode C for that matter) is actually correct? Particularly in respect of non radio or aircraft not receiving any service ?
I am sure this will apply to the majority of flights in Class G, because the ATC system could not cope if everyone called up a radar unit to have their mode C/mode S verified....... now there's a thought :E

slim_slag
22nd Aug 2006, 08:58
So what you mean is that pilots of TCAS-equipped aircraft will now be given collision avoidance instructions for against others potentially on a collision course with them, where previously they wouldn't have seen them at all?Well yes, but the current assumption is that non-mode S aircraft remain clear of the airspace that the TCAS aircraft is in. So separation is 'guaranteed'. What appears to be driving this is a desire for TCAS-equipped aircraft to enter non CAS. This is no doubt driven by the desire of airlines to make more money, and the way it is being proposed means the GA community are paying to install equipment which will provide GA negligible benefit, and for some even make it impractical to continue to fly. It's an airspace grab in another guise, being funded by the guy in his spamcan.

jabberwok
22nd Aug 2006, 09:05
IO540 - if you can't understand that flying 'blind' without knowing what else is around is dangerous, then I query your airmanship and judgement. You don't need 'supporting evidence' to support what something which is fundamentally axiomatic. Rely on statistics and you may well become one yourself.

I bet you never flew with Loganair then..

Stornoway, Benbecula, Tiree, Islay, Campbeltown, Londonderry. Absolutely crammed with airways to choose from and radar controllers begging to talk to you. :}

Beagle must be aware that his views are, in some parts of the UK, a theoretical ideal rather than a practical reality. No doubt he would like me to rip out the IAP's in my manual for all those airfields without radar cover.

tmmorris
22nd Aug 2006, 09:45
I'm sorry, BEagle, because I usually agree with you, but I'm afraid that as IO540 says, IFR OCAS with only a FIS (if that) is routine in some parts of the UK. There's no getting around it. I don't do it regularly now, as it's against our club SOPs, but even then it is sometimes unavoidable; as IO540 says, what are you supposed to do when 'dumped' by a LARS unit without anyone else to talk to? And even when all goes according to plan, you can find you have 5-10 minutes between being handed off by one controller and being visible on radar to the next. A couple of examples:

an OCAS IFR flight EGUB-EGXE: East Midlands couldn't pick me up initially even though I was at FL30 and requesting a climb to FL50;

an OCAS IFR flight Shobdon to EGUB; after departing Shobdon and climbing into IMC Gloucester couldn't pick me up until about 10 minutes out from Shobdon.

In both cases there was nothing I could do but sit tight and wait for radar cover.

What's stopped IO540 crashing is indeed the 'big sky' theory (plus the IFRs, of course, which were designed precisely with this in mind). As he says, there just isn't the evidence to back up your claim - mid-airs just don't happen like this. Far more dangerous are VFR mid-airs in the vicinity of airfields, or IFR CFIT incidents, neither of which are solved by radar cover.

Tim

BEagle
22nd Aug 2006, 10:10
It'll take just one mid-air under such circumstances and the IMC-outside-CAS-without-radar big-sky-theory risk takers will probably find the rules changed. Particularly if the pieces of aeroplane and human raining down from the sky did so over a populated area.

I suspect that the only reason it isn't already banned is that NATS know full well that they haven't got the infrastructure to cope with providing full radar service outside CAS. Additionally, more and more military aerodromes have closed over the years, reducing LARS cover substantially.

IMC outside CAS without RIS or RAS is specifically banned under my Club's Flying Order Book as well.

Out of interest, what was the cloudbase when you left Shobdon?

smarthawke
22nd Aug 2006, 11:56
The only 'monthly' mag to cover this saga I've seen recently is the present (September) 'Today's Pilot' - both in the editorial and in a stand-alone article. Interesting info and points made.

Now do I invest in a new transponder now (it's started to play up but Day-VFR use only) or wait a while? Me thinks I'll wait a bit longer....

robin
22nd Aug 2006, 13:14
Additionally, more and more military aerodromes have closed over the years, reducing LARS cover substantially.

When I went to FFF last weekend I spoke to a CAA rep who suggested that all aircraft would always be talking to a radar controller or at least a LARS service.

So if the CAA don't understand the limitations on some of the LARS stations (not at weekends and not after 4.00pm) or the growing gaps or the times they ask you to go away, then what are they doing proposing this RIA

What possible use is it to aircraft not receiving a radar service.

Sedbergh
22nd Aug 2006, 13:35
One feels very tempted to try to organise an "everybody in the air request RIS at once" event to demonstrate to the CAA what could happen with their Mode S proposal.

But since a very limited number of people rely on RIS for real and trying to fuse the system would be irresponsible, I won't.

I was in a thermal with 10 other gliders a couple of weeks ago. Do you suppose Mode S and LARS/RIS could have maintained separation?

mm_flynn
22nd Aug 2006, 14:08
It'll take just one mid-air under such circumstances and the IMC-outside-CAS-without-radar big-sky-theory risk takers will probably find the rules changed. Particularly if the pieces of aeroplane and human raining down from the sky did so over a populated area.

BEagle,
Mid-airs happen and the rules aren't suddenly changed. They are reviewed to see if the balance of risk is correctly assessed.

Some times they result in rule changes like the Ceritos Crash that brought Mode C veils to the US terminal areas, or the airliner/airliner mid-air over the Grand Canyon that brought class A airspace above FL180 in the US.

Sometimes they result in a review and no change (the periodic GA/GA or GA/Mil mid airs in VFR) or international standardisation of crew responses (two airlines with ACAS under Radar Control in Germany).

The complexity of changing the UK airspace, regulation, infrastructure, etc. to move to an environment where ATC service (could be procedural or radar) is required to fly IMC in Class G is enormous. It would have to be a spectacular incident - and more likely would result in regulation or SOP for the airlines not to fly outside Radar Coverage in Class G.

Now anyone equipped to fly IFR who is trudging along in IMC not receiving a Radar Service AND not squawking (ideally Mode C/S) is taking totally unnecessary risks - unless they are a glider :eek:

BEagle
22nd Aug 2006, 14:19
On a different note, are the military to be exempted from this 'Mandatory Mode S' proposal?

If so, then why?

robin
22nd Aug 2006, 14:59
Yep

They are trialling it in some of the fleet, but basically FJs won't be fitted

tmmorris
22nd Aug 2006, 15:51
To be honest, I can't remember - it was a couple of years ago. I'd come down VFR (scud-running) from Sleap and wasn't happy doing that really in an area with so many mountains, hence the decision to go back IFR. I seem to remember the scud-running was at about 1500' AMSL which means the cloudbase would have been c. 1200' AAL. With hindsight I could have scud-run until Gloucester picked me up, but I'd entered IMC before QSY-ing from Shobdon so I was stuck with it...

It's all very well having club rules (this was actually before I joined my current club anyway) but they are meaningless when as IO540 says you are dumped with 'squawk 7000, freecall enroute, good day'.

Tim

jabberwok
22nd Aug 2006, 17:08
They are trialling it in some of the fleet, but basically FJs won't be fitted

The trial is quite extensive with approx 180 aircraft so far equipped. FJ's do indeed seem to be exempt but a couple of Tornado's have been picked up sending Mode S codes.

BEagle
22nd Aug 2006, 17:20
That would mean a cloudbase of about 2300 ft amsl?

Hmm - safety altitude on that leg is....?

IMC below safety altitude and without radar? I think I'd sooner have flown at around 1800 ft QNH under VFR.

I guess all the military's civil-registered Tutors and Vigilants won't be exempt from the Mode S proposals then?

tmmorris
22nd Aug 2006, 17:32
Not sure how you worked that out - as I said, cloudbase was c. 1500ft amsl, or 1200ft aal. I was only below MSA for the time required to climb (over the flat terrain to the east of EGBS) to my cruising altitude/FL. Believe me, I'd have been happy at 1800ft VFR too. But with a cloudbase at 1500ft I decided I would be safer IFR in IMC - and expected to get a radar service sooner.

I'm not saying I did the right thing - just that sometimes, as then, IFR OCAS without radar service is unavoidable at the moment. Of course, it would be great if radar cover was universal. But it ain't.

Particularly irritating on that trip is that NATS has a radar head near Gloucester but because they are privatised, they don't supply Gloucester with the feed - and Gloucester can't afford to pay for it. Gloucester is primary only - with SSR they could probably have given me a radar service immediately after I left Shobdon.

Tim

bookworm
22nd Aug 2006, 17:55
I'm not saying I did the right thing - just that sometimes, as then, IFR OCAS without radar service is unavoidable at the moment.

Of course you did the right thing. Not only is there a greater risk of collision with the ground in the cloud, there are probably many fewer potential conflicts than with the VFR flights bimbling around in the 200 ft just below the cloud.

We all like to think that collision avoidance in VMC is assured by see-and-avoid, and that collisions in VMC only happen to "bad pilots". In reality, collision avoidance in VMC is statistical, just as it is in IMC. Play the odds wisely.

BEagle
22nd Aug 2006, 18:47
tmm - sorry, I misread the chart. Shobdon is 300 ft(ish) above sea level -it is the hills a couple of milesto the north which are 1000 ft amsl. But the hills between Sleap and Shobdon poke up to 1693 ft amsl.... I guess it was an 'interesting trip' from Sleap?

Personally I would have been very loath to leave Sleap at all, given those conditions. Had I done so, it would have been VFR and a very carefully plotted route. Aided, as IO540 will be pleased to learn, by carefully chosen GPS waypoints.

However, what I find very interesting is the fact that NATS seemingly put a price on safety concerning the feed of SSR information to Staverton. That is outrageous! Perhaps the issue should be raised in the response to the CAA's Mode S consultation?

You could have had a full Mode S installation and have been talking to Staverton shortly after having to make an unplanned climb into cloud. Yet Staverton couldn't have helped you because they couldn't afford the SSR feed? Is that really true?? If so, heads at the CAA, DfT, NATS or whoever should roll!

mm_flynn
22nd Aug 2006, 19:16
However, what I find very interesting is the fact that NATS seemingly put a price on safety concerning the feed of SSR information to Staverton. That is outrageous! Perhaps the issue should be raised in the response to the CAA's Mode S consultation?
You could have had a full Mode S installation and have been talking to Staverton shortly after having to make an unplanned climb into cloud. Yet Staverton couldn't have helped you because they couldn't afford the SSR feed? Is that really true?? If so, heads at the CAA, DfT, NATS or whoever should roll!

I was in Coventry's tower 6 months ago and they also don't have SSR because of the cost of getting the data link (I was told), even though Birmingham is just a few miles away. I think they are planning to put their own SSR in (I can't believe this is cheaper :ugh:) and even better it is another ground station lighting up all of the transponders reenforcing the 'need' for Mode S.

IO540
23rd Aug 2006, 06:23
I suspect that the only reason it isn't already banned is that NATS know full well that they haven't got the infrastructure to cope with providing full radar service outside CAS

I am sure that's true. In my native language, there is a saying which (translating very poorly into English as tends to be the case with word plays) goes something like: if you had fish up your ar5e then they wouldn't be in the pond.

Also I am not taking any "GPS baits", sorry Beagle :)

This whole business is run by anally retentive people. Technically there is no reason why every airfield operator should not be able to have a radar feed from NATS. It could be provided via a website. The amount of data to be transferred every few seconds is a few hundred bytes at most.

One problem is that NATS would charge for it, and most airfields won't pay for it (or for anything else for that matter, like a shovel and a wheelbarrow for filling potholes). The other problem is that the CAA would never allow "non qualified" people to see it.

In France, it appears common enough for airports without radar to have a radar feed appearing on a screen. Must be great for situational awareness.

Sedbergh
23rd Aug 2006, 07:27
OK guys, enough of the nit picking. The consultation period ends very soon now. Please get your views (in whichever direction) to the CAA as soon as possible.

Personally I am against the proposal on the grounds of high initial and ongoing cost against nil benefit to most users of light flying machines.:{

However the CAA electronic response form is so slanted that almost any reply could be interpreted as "favourable". Therefore I recommend that an "against" opinion should be voiced in a letter, copied to your MP.:ok:

tmmorris
23rd Aug 2006, 08:04
I guess it was an 'interesting trip' from Sleap?

I should confess at this point that despite visiting the facilities before departing Sleap, I quickly became aware that I would need to land to answer the call of nature very soon. I should really have abandoned the plan to go to Sleap at all and simply diverted home - or to Staverton - but I pressed on VFR in order to get to a loo quicker. Yes, VFR scud-running at 1500ft with the Long Mynd at 1693ft wasn't clever, and in fact has simply strengthened my resolve, as bookworm says, to get above MSA first and worry about the radar service second.

Tim

robin
23rd Aug 2006, 08:34
OK guys, enough of the nit picking. The consultation period ends very soon now. Please get your views (in whichever direction) to the CAA as soon as possible.
Personally I am against the proposal on the grounds of high initial and ongoing cost against nil benefit to most users of light flying machines.:{
However the CAA electronic response form is so slanted that almost any reply could be interpreted as "favourable". Therefore I recommend that an "against" opinion should be voiced in a letter, copied to your MP.:ok:

Spot on Sedburgh. There are only a few days left now, so if you haven't done so, get your response in.

Having seen a number of different responses already, I think the CAA will be taken aback by the vehemence of some of the views, although whether or not it will be enough for them to think again is another matter.

At any rate we have identified a lot of the inconsistencies and downright fiddling of the data in the RIA, sufficient to take it higher if necessary

So make sure you add your names and views to the consultation before 17.00hrs on the 29th August

BEagle
23rd Aug 2006, 10:02
Fair call, tmm! Joking aside, the debilitating effect of 'needing to go' can be very significant.

At least if more units had SSR feeds, the risk of the big sky theory failing would be less. Your 'bad weather pull-up' is (or was) often something faced in the military. Climb at best performance to Safety Altitude, then adjust to the correct quadrantal and call for radar if still IMC.

A corollary to the CAA's partial RIA might perhaps be a call for greater availability of SSR readout in ATC units? Not much point in being made to fit a transponder of any Mode if there's no-one able to see your squawk under the conditions you describe!

Jumbo Driver
23rd Aug 2006, 10:22
Can I add my plea to those who have not yet responded to the CAA Consultation Paper. I heard earlier today that they have only received a few hundred responses so far - we really need to make our case heard.

It needs to be in by 1700 on Tuesday 29 August 2006; there are only 6 days to go, with a Bank Holiday weekend in between.

The link again:

http://www.caa.co.uk/default.aspx?categoryid=7&pagetype=90&pageid=6476

Do it now !!


JD

BEagle
23rd Aug 2006, 13:54
After much thought, I now suggest that:

1. With effect from 1 Apr 08, increased surveillance and collison protection should be introduced. This must be reasonable, affordable and proportionate to the degree of protection sought.

2. With effect from 1 Apr 08, Mode A should no longer be permitted within UK airspace.

3. No new Mode C installations should be approved after 31 Mar 10.

4. Minimum transponder requirements after 31 Mar 08 should be as per the following table:

http://i14.photobucket.com/albums/a341/nw969/xpdr.jpg

Sorry if it's a little large. Anyone who wishes to cut and paste this into a response to the CAA RIA, please feel free to do so.

Jumbo Driver
23rd Aug 2006, 14:20
BEagle, I agree with all you say, except your item 3.

I see no reason why a VFR aircraft below 2000 Kg should not be permitted to install a transponder with Mode C, after 31 March 2010.

If I understand you correctly, you would require him to install Mode S (if he installed anything), even though he would not be required by your table to carry Mode S if he only intended to fly VFR in Classes D or G, or SVFR in Class A.



JD

:confused:

QDMQDMQDM
23rd Aug 2006, 15:39
BEagle, why do aircraft 2000-5700Kg go VFR Mode C in your scenario in class D airspace, but Mode S in E-G?

BEagle
23rd Aug 2006, 15:42
JD - Basically because, by then, it should be just as cheap to install Mode S as the market for Mode C would probably be no longer viable.

QDMQDMQDM - buggah! Damn cut and paste. It should have read:

2000-5700 kg. Class E-G IFR: Mode S, VFR: Mode C optional, Mode A not permitted.

New table:

http://i14.photobucket.com/albums/a341/nw969/xpdr2.jpg

QDMQDMQDM
23rd Aug 2006, 15:58
Looks like a good scenario to me. Presumably, you're sending it to the CAA?

The real crux about this preposterous proposal for Mode S on all flying machines all the time is that it is unenforceable and there is no point having an unenforceable law. It simply makes criminals out of law abiding citizens.

QDM

IO540
23rd Aug 2006, 16:04
It would be enforceable allright; it would just stop a lot of people flying.

Most pilots are law obiding people and, as a minimum, won't fly if their insurance is void the moment they get airborne (because of not meeting the equipment carriage requirements for the airspace).

I think beagle's proposal is excellent.

BEagle
23rd Aug 2006, 16:09
Thanks for your comments, chums.

It has indeed been sent to the CAA and to others.

You are welcome to use it as you wish.

QDMQDMQDM
23rd Aug 2006, 16:31
Most pilots are law obiding people and, as a minimum, won't fly if their insurance is void the moment they get airborne (because of not meeting the equipment carriage requirements for the airspace).


IO540, you are completely wrong if you think I am not going to go for a late evening tootle around completely empty North Devon airspace just because my Mode S transponder is u/s. I am afraid the rest of the muddy welly wearing PFA brigade will be the same.

And even if it is working, I may forget to switch it on.

It is unenforceable.

Single Spey
23rd Aug 2006, 17:51
BEagle

Interesting proposal. However:

1) Class D airspace is a known traffic environment so ATC should not require you to have any transponder. By mandating a Mode C transponder ATC will now have no way of positively identifying you on radar except by primary radar and I cannot see many ATCOS wishing to give ident turns. There will also be no way for one controller (Approach) to know that the Mode C is verified (by Zone for example) unless they pass traffic information and maintain track identity. So this will be next to useless for any separation purposes.

2) What is the benefit in any transponder equippage in unregulated airspace? So that the TCAS equipped aircraft can take collision avoidance? Faced with a number of conflictions in a limited area, all equipped with Mode C, the TCAS algorithm has difficulty forming the correct tracks and evaluating the correct TA/RA. TCAS was designed to operate on fairly widely separated tracks with relatively constant flight paths. Its capability in the GA environment has not been proven to be safe.

3) Continued use of Mode C will not meet the CAA requirement to clean up the RF spectrum. Ground interrogators may still receive garbled replies and Fruit. TCAS will only be able to detect the Mode C equipped aircraft with a Mode C All Call transmission which is still damaging to the RF environmment.



In summary, given that you will not permit new Mode C installations from 2010, your proposal is a transition plan to Mode S equippage with some exemptions, but still does not give a quantitative estimate of how it will improve safety.

And where is the evidence/consultation that resulted in 'improved technical interoperabilty for ALL aircraft' being the only option under consideration?

IO540
23rd Aug 2006, 17:56
Class D airspace is a known traffic environment

With perfect navigation, and everybody on the radio to the controlling unit, it could be.

What is the benefit in any transponder equippage in unregulated airspace

Probably the biggest one is in case the pilot wonders out of unregulated airspace.

Continued use of Mode C will not meet the CAA requirement to clean up the RF spectrum.

It would eventually, as people chuck out the old stuff. A lot of Mode C units are already ancient and rotting happily in British winters, and most new ones will probably be fitted to IFR tourers who have just had to rip them out and put in Mode S :) So there is a nice supply of cheap Mode C units. Currently, IFR pilots are having to sell them for a few hundred quid on U.S. Ebay.

robin
23rd Aug 2006, 18:54
Class D airspace is a known traffic environment
With perfect navigation, and everybody on the radio to the controlling unit, it could be.
What is the benefit in any transponder equippage in unregulated airspace
Probably the biggest one is in case the pilot wonders out of unregulated airspace..

No - if a non-radio aircraft wanders into CAS, what is the benefit? Surely it will show up as a primary contact in any event. It certainly won't enable the ATCO to call up the miscreant, although it will allow them to send an automated fine and 'you've lost your licence' to the owner

Continued use of Mode C will not meet the CAA requirement to clean up the RF spectrum.
It would eventually, as people chuck out the old stuff. A lot of Mode C units are already ancient and rotting happily in British winters, and most new ones will probably be fitted to IFR tourers who have just had to rip them out and put in Mode S :) So there is a nice supply of cheap Mode C units. Currently, IFR pilots are having to sell them for a few hundred quid on U.S. Ebay.

But as QDM says, when flying for an evening bimble miles from any area of CAS, why is it necessary even to carry Mode C

DaveW
23rd Aug 2006, 19:06
But as QDM says, when flying for an evening bimble miles from any area of CAS, why is it necessary even to carry Mode C

BEagle's proposal doesn't say it is: "Class E-G: Mode C optional".

Not convinced why Mode A should be prohibited, though. Say it isn't recommended, sure, but there are lots of aircraft around with xpdrs but no ALT encoding. Is this worse than nothing at all?

BEagle
23rd Aug 2006, 19:13
Class D airspace is a known traffic environment.

It should be, in a perfect world. And then there wouldn't be any need for TCAS, of course. But the primary aime of TCAS is to resolve conflicts caused when pilots and/or ATC foul up. As happens. 100% height-reporting traffic will at least ensure that only genuine RAs are generated.

What is the benefit in any transponder equippage in unregulated airspace?

Flight in IMC is permitted outside CAS in UK airspace. Hence whilst we still have reasonable areas of free airspace where the 'muddy welly' PFA chaps can indeed enjoy lawful, non-RT VFR pottering - and long may that continue - such airspace may also be used by pilots wishing to fly in IMC. Without any transponder they would have to rely on the increasingly rare availability of primary radar for traffic separation - or risk reliance upon the statistics of the 'big sky' theory.

There will also be no way for one controller (Approach) to know that the Mode C is verified (by Zone for example) unless they pass traffic information and maintain track identity.

So pass the information on then!

Ground interrogators may still receive garbled replies and Fruit. TCAS will only be able to detect the Mode C equipped aircraft with a Mode C All Call transmission which is still damaging to the RF environmment.

Reply Garble is only likely with aircraft in very close proximity (such as in a holding pattern) and FRUIT is far less likely in terminal areas rather than in en-route Class A-C airspace. Hence my proposal for proportionate technical requirements rather than heavy-handed universal Mode S. I also have little faith in the CAA's assessment of the so-called 'damaging' L-band environment. It is probably as much of a fable as the nonsense of FM-immunity has proved to be.


And where is the evidence/consultation that resulted in 'improved technical interoperabilty for ALL aircraft' being the only option under consideration.

Quite. Don't ask me, ask the DAP.

Increasing numbers of CAT operations are being flown from regional airports without direct access to Class A - or even Class D`airspace. Unless the Air Traffickers are to be granted vaste chunks of additional regulated airspace, I consider that we need to provide improved conspicuity under IFR by mandating height encoding transponders for all aircraft flying under IFR. Which can, of course, be in 100% VMC. But spurious or ambiguous TCAS TAs generated against Mode A help no-one - hence I still believe that no-one flying an aeroplane of < 5700 kg under VFR in the 'open FIR' should be compelled to carry a transponder, but if they do, it must have height encoding.

robin
23rd Aug 2006, 19:36
[I] But spurious or ambiguous TCAS TAs generated against Mode A help no-one - hence I still believe that no-one flying an aeroplane of < 5700 kg under VFR in the 'open FIR' should be compelled to carry a transponder, but if they do, it must have height encoding.

Sorry, I'm not following this, but I've no knowledge of how this works

You are saying that we need to carry a height encoding transponder IF we decide to carry one, so that IFR pilots (who may be passing by) can resolve conflicts using TCAS.

We may chose not to fit a transponder at all, as microlights and gliders are exempt under your proposal, and our Cubs, Aeroncas and Jodels can opt not to carry one, neither will military FJ traffic. So the odds are that the IFR pilot who may not be receiving an ATC service will have no idea of any traffic except the minority that choose to squawk. If he chooses to change course to resolve any conflict, then how does he know he isn't about to turn into greater danger?

The same things would happen if a Chavair flight cuts the corner into Class G.

Is this not a problem?

BEagle
23rd Aug 2006, 19:47
TCAS either gives 'Traffic Advisories'(TA) which highlight the presence of all other transponding aircraft within a certain height and range envelope - or 'Resolution Advisories'(RA) if a clear risk of collision exists. To generate a RA, TCAS must know the height of the other traffic using either the Mode C or Mode S information from the other traffic.

TAs would be generated against any Mode A aircraft within range. But those could be spurious if the traffic was actually well separated by altitude - or, perhaps worse, should really have been RAs but couldn't be because TCAS didn't know the height of the Mode A aircraft.

I consider such dangerously ambiguous TAs worse than useless - and a bigger distraction than no information at all.

If 'Chavair' enters Class G airspace under IFR, at least he would get TCAS protection against Mode C aircraft flying in IMC without any radar service - as is currently legal in the UK. But the chances of VFR traffic colliding with 'Chavair' in Class G is far less likely - and is not sufficiently great to merit universal Mode S for all aircraft.

One final point. TCAS azimuth resolution is relatively poor. So it is never used by pilots to 'change course to avoid conflict'.

Single Spey
23rd Aug 2006, 20:43
TCAS azimuth resolution is relatively poor. So it is never used by pilots to 'change course to avoid conflict'.

BEagle, you forgot the smiley ;)

avidflyer
23rd Aug 2006, 21:48
I've just returned from the consultation meeting at Barton and put to the technical chap there (sorry, forgot the name) a proposal very similar to Beagle's. He agreed it would be an effective interim solution if you assume that existing Mode C transponders would all be replaced gradually so extending the 1090MHz saturation deadline past the date at which Mode C would have disappeared (no timescale given though). Interestingly, he said there had been the same solution proposed at Lasham.

Aunt Rimmer
24th Aug 2006, 01:09
There will also be no way for one controller (Approach) to know that the Mode C is verified (by Zone for example) unless they pass traffic information and maintain track identity.
So pass the information on then!

BEags -with all due respect. When I am busy, the last thing I would have time for is passing traffic info on to (presumably) all the adjacent radar units, on all the (newly transponding) returns that I might be giving a service to just in case they might want to know about it. Conversely, the second last thing I have time for is continually answering a ringing landline from someone asking for traffic info on traffic that I may, or may not, be working. To suggest otherwise shows that you really need a visit (and beer) to the nearest friendly Scottish Centre methinks.

But spurious or ambiguous TCAS TAs generated against Mode A help no-one - hence I still believe that no-one flying an aeroplane of < 5700 kg under VFR in the 'open FIR' should be compelled to carry a transponder, but if they do, it must have height encoding.

Again the question is posed. How does anyone know that that Mode C, or Mode S height readout is actually verified ? Bear in mind that TCAS can only provide separation based on that vertical info (and not on any azimuth info), what happens if that height readout is wrong ? There have already been intersting TCAS incidents with ac climbing (into) conflicting traffic, because the Mode C was wrong and indicated (wrongly) that the traffic was below when in fact it was above !! :eek:

A large increase in the number of transponders will surely lead to a proportionate increase in the number of incorrect height readouts ?

Now, what if EVERYONE who had to have a Mode S installed called up their nearest ATC unit to get it validated EVERY time they went flying - how long before CAA would be issuing safety notices advising people not to do that as it was overloading controllers ....... my guess .... not long. Rather ironic don't you think ?

What also happens if Pilot A inadvertantly has the wrong pressure setting on his altimeter ? Am I right in thinking that TCAS assumes all height readouts are based on 1013mb ? What happens below the transition altitude ?

Although I am still reading through your fine table, I still also disagree strongly about making a transponder compulsory for VFR in Class D - Our club operates quite happily in Class D airspace, using standard entry/exit lanes and procedures, which keep us separated from the IFR approaches and climbouts. A transponder is not mandatory at the moment and (more importantly) experience has shown that it isn't a problem. If it ain't broke don't fix it.

Now, sure, I am pi$$ed off at the prospect of having to shelve out (yet) another wad because of some potential CAA ruling ... I am still reeling from the CAA move on Engine TBO (March 2006). In one bureaucratic pen-stroke my 700/1500hr engine is now declared unfit for flying club rental, because it is over 12 years old - cost to resolve this .. ? £20k ! :mad:

My anger on Mode S (and the false premise being used to push it) would be abated somewhat if it was being paid for by those who want/demand/benefit financially from it. I also note that in the CAA RIA, they make a meal out of all the costs to GA/Business Aviation.

For all their accountants credentials it is surprising that they fail to point out the quantifiable commercial gains for airlines of making everyone else install Mode S. That is a figure I would like to see. It shouldn't be too difficult for the 'experts' to come up with one. Then perhaps the equation would be less one-sided and more transparent.

I would also like to know who most PPruners think should pay for Mode S?

GA ? Airlines ? Or hypothecated from Govts rip-off tax on Avgas ? Or the CAA/NATS ?

jabberwok
24th Aug 2006, 01:59
What also happens if Pilot A inadvertantly has the wrong pressure setting on his altimeter ? Am I right in thinking that TCAS assumes all height readouts are based on 1013mb ? What happens below the transition altitude ?

It's irrelevant. All transmitted heights are SPS regardless of actual altimeter setting. TCAS is therefore correctly determining the difference between relative altitudes even though these values are otherwise meaningless below TA.

Aunt Rimmer
24th Aug 2006, 09:38
It's irrelevant. All transmitted heights are SPS regardless of actual altimeter setting. TCAS is therefore correctly determining the difference between relative altitudes even though these values are otherwise meaningless below TA.

In the cold light of morning, yes I can see clearly now :ugh:

Blame it on a late night beer ;) - and brain stuck in a wee loop.

Of course, what I was confusing it with is when someone sets the wrong pressure setting and my radar display then shows up for example FL064 instead of FL070 - the error is in the input, but the height readout is still correct (based on 1013mb) .....

..... ASSUMING THE MODE C IS WORKING PROPERLY ...... (which is still an unanswered point) ;)

NorthSouth
24th Aug 2006, 13:04
such airspace may also be used by pilots wishing to fly in IMC. Without any transponder they would have to rely on the increasingly rare availability of primary radar for traffic separationWhy rare? There's no decline in the number of primary radars, quite the opposite - Doncaster and Inverness about to get their own, to name only two. And one of the very few examples of an SSR-only radar station in the UK recently had its primary reinstated. MoD has always opposed SSR-only and I can't see that changing.
NS

jabberwok
24th Aug 2006, 14:03
Of course, what I was confusing it with is when someone sets the wrong pressure setting and my radar display then shows up for example FL064 instead of FL070 - the error is in the input, but the height readout is still correct (based on 1013mb) .....

Yes - that the difference. We have to dial in a TA and QNH on the radar to make the altitude show a correct value. For pure TCAS work the datum is irrelevant.

BEagle
24th Aug 2006, 16:28
One concept suggested in the past was for a particular general Mode C squawk to indicate that a verified Mode C check had been carried out. But, of course, that would be too easy to abuse.

However, if the verifying unit issued a 'verification number' which the pilot then acknowledged, at least it would deter such abuse. E.g. the last 2 letters of the ICAO code plus the Julian date, then the next number in sequence plus the last 2 codes of the registration? So, for example, Brize Radar issuing a Mode C check to the 7th aircraft of the day, G-ABCD, on October 18th would issue 'verification VN291007CD'?

More work for ATC, perhaps - but probably worth it to have verified Mode C squawks generally available?

Jumbo Driver
24th Aug 2006, 20:00
However, if the verifying unit issued a 'verification number' which the pilot then acknowledged, at least it would deter such abuse. E.g. the last 2 letters of the ICAO code plus the Julian date, then the next number in sequence plus the last 2 codes of the registration? So, for example, Brize Radar issuing a Mode C check to the 7th aircraft of the day, G-ABCD, on October 18th would issue 'verification VN291007CD'?


Takes me back to the Air Defence Numbers we used to have to overfly Burma ...


JD
;)

Aunt Rimmer
24th Aug 2006, 21:26
However, if the verifying unit issued a 'verification number' which the pilot then acknowledged, at least it would deter such abuse. E.g. the last 2 letters of the ICAO code plus the Julian date, then the next number in sequence plus the last 2 codes of the registration? So, for example, Brize Radar issuing a Mode C check to the 7th aircraft of the day, G-ABCD, on October 18th would issue 'verification VN291007CD'?
More work for ATC, perhaps - but probably worth it to have verified Mode C squawks generally available?
You are taking the pi$$ now aren't you ? Please tell me that you are ? If not, common-sense and reason have finally been chucked out the window.

I've got a better idea. Why not mandate that every aircraft must have at least 2 seats and that one of them must be occupied by a valid ATCO, with his own Personal Radar .. oh dear then you'd probably need an extra seat for the CAA man to verifiy the verifier .... "just in case". Flourescent jackets would of course be compulsory ....

Better still .... gie it a rest - we are generally overcontrolled as VFR pilots and if you are being serious .... :ugh: .... this rather smacks of the 'fighter controller' mindset, that requires that 'everything' is a threat until it has been identified.

It reminds me of the battle that was fought last year against the National Park in Loch lomond who were trying to ban seaplanes, for no other reason than the fact that what they don't understand they condemn.

So, the point was being made by National Park numpties (mostly Labour cooncillors BTW) (must be something about the nanny state mentality) about how dangerous it was having seaplanes landing near boats .. "they might collide" .. was the siren banshee call ... "how are you going to avoid boats"? etc..etc..

It was then pointed out to aforesaid numpties that the main A82 road , with some 35000 cars a day, travelling at speeds in excess of 60mph each way :eek: (120mph closing) manage to miss each other by only 6 or 7 feet ...... My goodness how do they do that ??!!!

.... by LOOKING OUT THE :mad: ING WINDOW.

Look - we don't need the aviation community adding to or going along with regulation for regulations sake ..... it's a nanny state and you either fight it or you get sucked in as a conspirator by giving these nanny state views legitimacy ... if you don't believe me have a look at the next daft proposal ...
http://news.scotsman.com/politics.cfm?id=1221422006

BEagle
24th Aug 2006, 21:48
Thank you for your valuable and reasoned contribution to the debate.....

Aunt Rimmer
25th Aug 2006, 05:07
Thank you for your valuable and reasoned contribution to the debate.....
Always a pleasure :E

So you really were being serious then ? :confused:

I didn't think I would need to explain why that proposal (Mode C Verification Number Allocation) is ludicrous, because I thought you were joking, and that it was self-evident. Don't be so offended if I choose to disagree with you, and if my tone may seem slightly aggressive :E . I AM angry at the Mode S proposals and I will make my views known, hopefully strongly and frankly.

(First some ground rules)
I am very much on the side of GA. I fly whenever I can. I regard myself as an aviation professional who is lucky enough to indulge a passion for flying. I believe these rights have been whittled away under constant and sustained attack from faceless bureaucrats and accountants for the last 10 years.
I am against over regulation (particularly for regulations sake or because it 'fits' somebodies big plan from on high)
I am a current ATCO and do my best to bend over backwards (not forwards tho) to help out all pilots.
I work Area sectors, 200x200 miles on a 15inch monitor - this encompasses huge areas in Scotland where there is no LARS service provider anyway - .

My prime task (as I am told by my employer) is toward Civil Air Transport. I personally didn't agree with privatising ATC because my feeling was then that everyone was equal but that would change ..... - well it's here now, so we have to live with it. The truth is if EVERYBODY called up for (or demanded?) a service the system would not cope because there really are not enough controllers to cope with that demand, even at Scottish ACC.

Now with respect to GA - maybe the situation is different in Merry Old England? Maybe you have plenty of free LARS units to call upon? I think we have two (Leuchars and Lossie) in the whole of Scotland, and even then only Mon-Fri and not in the busiest areas. ScACC provides it when we can - ie. if the controller can do it AND vector stuff in the airways, ADRs and UARs, but radar (and frequency) cover is not tremendous at low level, especially over the mountains. Below 6-7000 feet you will struggle to get a radar return, and below 4000 R/T will be suspect.

GA generally gets on with it without bothering or demanding much of the current system - and it works quite happily.

From an ATC point of view I (and most of the ATCOs I know who fly - which sadly is an ever-diminishing number) think it is much better if VFR ops are allowed or left to get on with it - sure, call up when you really need something, but if the CAA start to mandate the likes of Mode S, and then some authority insisted on allocating an idea like BEagle's "Mode C Verification Code" , very quickly you WILL swamp the system. The system (being naturally sympathetic to GA :ugh: ) will then probably justify itself and start trying to look harder at ways of restricting you to prevent the swamping.

Maybe there are different issues in the important old southeast round the London TMA, well I still don't think it's a valid reason for the Deskbound Ones to impose unnecessary and expensive solutions on the rest of the country.

Sedbergh
29th Aug 2006, 07:07
Well guys

If you didn't respond to the CAA RIA

IT'S TOO LATE NOW!!!:\

If you get stuck with having to shell out loads of money for no discernable return to your aviation activities then ..............:{

NorthSouth
29th Aug 2006, 07:42
Well guys
If you didn't respond to the CAA RIA
IT'S TOO LATE NOW!!!Not quite - you've got till 1700 today. You can respond online or e-mail your response to DAP.
NS

Pitts2112
30th Aug 2006, 06:30
OK, this is probably going to be one of those questions to which the answer is so obvious that people stopped discussing it years ago but it seems that one of the issues that plagues the current ATC system is being unable to tell at what altitude an unidentified aircraft is flying, thereby not knowing if he's in, under, or over a particular piece of airspace. Hence Mode C with altitude encoding.

Here's my question. If airborne radar exists which can track fast moving targets from a fast moving platform, and sort out everything about everyones' positions and vectors to within a gnat's whisker, why can't ATC radar do the same? In other words, why does ATC radar need the aircraft to tell it what altitude it's at? I would have thought radar could be much more accurate than steam-driven altimeters anyway.

Am I missing something here?

VP959
30th Aug 2006, 08:03
If airborne radar exists which can track fast moving targets from a fast moving platform, and sort out everything about everyones' positions and vectors to within a gnat's whisker, why can't ATC radar do the same? In other words, why does ATC radar need the aircraft to tell it what altitude it's at? I would have thought radar could be much more accurate than steam-driven altimeters anyway.


Mechanically scanned radar heads suffer from relatively poor bearing discrimination, plus can only normally check azimuth or elevation separately; normally two synchronised heads are required to acquire azimuth and elevation data together.

The total bearing accuracy is typically about 1 degree at best, maybe worse than this in elevation, due largely to beam width limits. A target at 5000ft and 30 miles from the radar head has an elevation angle of less than 2 degrees, so sufficiently accurate height data is simply impossible to derive from conventional radar at realistic operating ranges.

It is possible to use radar to get better 3D pictures of close-in airspace using military phased, steerable array technology, but still not to the altitude accuracy needed to control lots of CAT at say 30 to 50 miles range. At the moment the civil radar heads used by ATC are a little bit more antiquated than the best military kit.

robin
30th Aug 2006, 09:31
Just seen this in the paper on the 'launch' of future usage of UAVs.

http://www.guardian.co.uk/uk_news/story/0,,1860787,00.html

I'm I right in thinking this was deliberatley held back until the day after the Mode S consultation closed, and if so, what does that say about the CAA's attitiude to the consultation?

bogcleaner
1st Sep 2006, 16:12
http://aviation-safety.net/database/record.php?id=20060828-1

Would suggest a good case for Mode S for anything airborne

DaveW
1st Sep 2006, 16:21
Would suggest a good case for Mode S for anything airborne

I'll look forward to wildlife (http://www.rapp.org/archives/2005/08/c130_bird_strike/) being fitted with Mode S sometime soon, then. :rolleyes:

This makes no such case, and neither would any other single data point.

Whilst we are speaking of this case possibly being used as spurious Mode S justification , though, I'd be interested to know:

1. If the Hawker 800 was fitted with Mode S itself?
2. If it was fitted with ACAS?

mm_flynn
1st Sep 2006, 18:20
I haven't looked but if the Hawker has 10 or more seats (seems likely) it is required to have ACAS. Given the high level of Mode S usage and ACAS in the states it would be realy surprising to find NetJets operating anything without both features (along with the full TAWS system the needed as well!)

zkdli
2nd Sep 2006, 09:01
check the thread on rumour and news!

Sedbergh
4th Sep 2006, 07:32
There was an interesting full page colour advert by Boeing no less in yesterday's Sunday Times saying how they are working on UAV's to improve all our lives etc etc.:uhoh:

So maybe Boeing should fit and service Mode S in all our flying machines free of charge?

Lucy Lastic
4th Sep 2006, 08:11
There was an interesting full page colour advert by Boeing no less in yesterday's Sunday Times saying how they are working on UAV's to improve all our lives etc etc.:uhoh:

You mean those nice UAVs designed to win our hearts and minds? Our hearts in one place and our minds spread somewhere else:E

So maybe Boeing should fit and service Mode S in all our flying machines free of charge?

Surely not. We all know how cash-strapped Boeing are, and our dear government feels that we should help them out

robin
4th Sep 2006, 15:31
Seems to demonstrate conclusively the CAA's lack of good faith in the Mode S consultation - they had already decided the conclusion and contracts signed halfway through the consultation process - nice one

Sedbergh
26th Oct 2006, 08:16
In the last issue of "Sailplane and Gliding" the BGA reports that the total number of responses to the CAA's Mode S "consultation" has been several times larger than number of responses to any previous CAA consultations
- so well done guys.
The BGA has also requested copies of any replies from members of parliament to those peeps who bothered to write to their MP about the consultation process.
Said copy of S&G also has a very interesting review of FLARM as a low-cost collision avoidance device for gliders/light aircraft.