Mode "S" - Rfq
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Mode "S" - RFC
Hi
In another thread (Proposal for PPLIR) we were discussing Mode S equipment.
Well, the CAA have published a consultative document about the carriage of Mode S equipment.
http://www.caa.co.uk/docs/7/DAP_SSM_...eS_SSR_ANO.pdf
If you don't speak up, you'll still have to pay up
BRL, this may need sticking for a couple of days, so it doesn't disappear before the weekday PPRuNers see it
In another thread (Proposal for PPLIR) we were discussing Mode S equipment.
Well, the CAA have published a consultative document about the carriage of Mode S equipment.
http://www.caa.co.uk/docs/7/DAP_SSM_...eS_SSR_ANO.pdf
If you don't speak up, you'll still have to pay up
BRL, this may need sticking for a couple of days, so it doesn't disappear before the weekday PPRuNers see it
Last edited by rustle; 24th Nov 2002 at 12:47.
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Should definitely have a sticky please.
From I admit a quick read I am struglling to fing a single mention of private aircraft.
These proposals potentially are not only concnerned with IFR or airways but all fo GA. We should consider that the cheapest mode S box is several thousands of pounds, never mind the cost of fitting.
From I admit a quick read I am struglling to fing a single mention of private aircraft.
These proposals potentially are not only concnerned with IFR or airways but all fo GA. We should consider that the cheapest mode S box is several thousands of pounds, never mind the cost of fitting.
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What does this mean for private GA, which it doesn't seem to mention? And what happened to the proposal to get everything which flies (including paragliders etc.) to carry one of these infernal boxes? Is that still the thinking? And how much is the cheapest GA Mode S box anyway?
rustle? Anyone?
Between this and the proposed Rule 5 amendment I feel like starting a 'Hands Off Our Airspace' movement. Bloody bureaucrats.
QDM
rustle? Anyone?
Between this and the proposed Rule 5 amendment I feel like starting a 'Hands Off Our Airspace' movement. Bloody bureaucrats.
QDM
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QDM,
GA is most definitely affected.
Original timings would have been (simplistically) IFR-ops require mode S by 2003, all other aircraft (incl. balloons/gliders/airships) by 2005.
CAA went for extension. IFR-ops by 2005, all others by 2008.
But, and this is worth remembering, AFAIK the other countries adopting Mode S have not yet agreed a deferral
There are currently ZERO Enhanced Mode S boxes available for GA.
Likely outcome from that is IFR-ops will have to seek exemption until the kit is available, on the basis that as soon as kit available, it will be fitted (including proving fitting "appointments" and proof-of-"purchase")
Estimated cost for an enhanced Mode S box: unknown - captive market, high R&D = give them a blank cheque
Quite important, really...
---------------------------------
There are currently three very significant things happening in UK that will have an affect on our hobby.
AIS changes
Rule 5
Mode S
Maybe I need to talk Mike into making our website permanent
GA is most definitely affected.
Original timings would have been (simplistically) IFR-ops require mode S by 2003, all other aircraft (incl. balloons/gliders/airships) by 2005.
CAA went for extension. IFR-ops by 2005, all others by 2008.
But, and this is worth remembering, AFAIK the other countries adopting Mode S have not yet agreed a deferral
There are currently ZERO Enhanced Mode S boxes available for GA.
Likely outcome from that is IFR-ops will have to seek exemption until the kit is available, on the basis that as soon as kit available, it will be fitted (including proving fitting "appointments" and proof-of-"purchase")
Estimated cost for an enhanced Mode S box: unknown - captive market, high R&D = give them a blank cheque
Quite important, really...
---------------------------------
There are currently three very significant things happening in UK that will have an affect on our hobby.
AIS changes
Rule 5
Mode S
Maybe I need to talk Mike into making our website permanent
Last edited by rustle; 25th Nov 2002 at 11:24.
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Does this seriously mean that if I were to go for a potter around the totally uncontrolled, empty airspace of North Devon, as I did this afternoon, that I would have to have a functioning Mode S transponder? What an incredible load of bollocks if that is so. What about non-radio aircraft, gliders and the like? This is ridiculous.
QDM
QDM
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QDM, you would have to have Mode S, I would in my glider, and so would everyone else from 2008.
It is possible that this would cause so much clutter on ATC screens that it would then be mandatory to switch it off in some areas, like in Holland beneath their TMA. A recent thread on PPrune ATC issues had several ATCO's saying that they could not cope with all GA including gliders etc. squawking.
(On good days, there are more gliders than anything else flying. During one day, it was found that about 350 transits of Didcot power station were made by gliders.)
The thread on the ATC forum I had in mind was called gliders and transponders, and included the following extracts:
-----------------------
posted 7th October 2002 13:39
In the netherlands gliders are obliged to squawk mode a/c everytime they are flying above 1200 ft. This rule comes into effect by 1-1-2003.
The reason, be-sides european regulations, is to enhance safety and avoid mid-air collisions.
The ironical thing is it is MOST STRICTLY FORBIDDEN to squawk below the schiphol tma........?
[snip]
----------------------------------------
posted 7th October 2002 14:53
I am both a controller and a glider pilot from Germany. I don´t like the idea of every glider having to squawk generally at all...from either side. First, there are not many certified transponders available suitable for gliders (they use a lot of electrical power). But most important is the fact that on a nice weekend there ARE already so many targets shown on my screen, that I can hardly see my IFR-traffic. If every glider would have to squawk when flying in controlled airspace I would go mad because I would see even less. [snip]
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posted 8th October 2002 09:33
Completely bonkers idea!
Quite apart from the fact that the SSR clutter on radar would drive us to distraction, the lateral and height envelope of a manouvering glider is so unpredictable it would be of little use to us in atc or a TCAS equipped aircraft.
I don't know about the rest of Europe, but in my experience the UK glider fraternity generally operate to very high standards, keeping us informed well in advance of their intentions/operations, and also generally manage to stay away from similarly busy airports/airfields.
----------------------------
It is possible that this would cause so much clutter on ATC screens that it would then be mandatory to switch it off in some areas, like in Holland beneath their TMA. A recent thread on PPrune ATC issues had several ATCO's saying that they could not cope with all GA including gliders etc. squawking.
(On good days, there are more gliders than anything else flying. During one day, it was found that about 350 transits of Didcot power station were made by gliders.)
The thread on the ATC forum I had in mind was called gliders and transponders, and included the following extracts:
-----------------------
posted 7th October 2002 13:39
In the netherlands gliders are obliged to squawk mode a/c everytime they are flying above 1200 ft. This rule comes into effect by 1-1-2003.
The reason, be-sides european regulations, is to enhance safety and avoid mid-air collisions.
The ironical thing is it is MOST STRICTLY FORBIDDEN to squawk below the schiphol tma........?
[snip]
----------------------------------------
posted 7th October 2002 14:53
I am both a controller and a glider pilot from Germany. I don´t like the idea of every glider having to squawk generally at all...from either side. First, there are not many certified transponders available suitable for gliders (they use a lot of electrical power). But most important is the fact that on a nice weekend there ARE already so many targets shown on my screen, that I can hardly see my IFR-traffic. If every glider would have to squawk when flying in controlled airspace I would go mad because I would see even less. [snip]
---------------------------------------
posted 8th October 2002 09:33
Completely bonkers idea!
Quite apart from the fact that the SSR clutter on radar would drive us to distraction, the lateral and height envelope of a manouvering glider is so unpredictable it would be of little use to us in atc or a TCAS equipped aircraft.
I don't know about the rest of Europe, but in my experience the UK glider fraternity generally operate to very high standards, keeping us informed well in advance of their intentions/operations, and also generally manage to stay away from similarly busy airports/airfields.
----------------------------
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Chris,
Just to clarify one aspect, the pilot would not, infact, switch off the transponder - ATC will filter it out and not display your data to avoid "clutter".
You will still be "squawking" (pardon the expression) so that TCAS still functions (notwithstanding the limitations you mention above)
So, buy the kit so you show up on radar, then we'll filter you out so that you don't again...
Just to clarify one aspect, the pilot would not, infact, switch off the transponder - ATC will filter it out and not display your data to avoid "clutter".
You will still be "squawking" (pardon the expression) so that TCAS still functions (notwithstanding the limitations you mention above)
So, buy the kit so you show up on radar, then we'll filter you out so that you don't again...
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OK, so lets see if I've got this straight.
We need to have Mode S transponders - with height readout, (I thought that was Mode C), so that TCAS will function properly.
At the moment, if I'm down at 1500' with my transponder on and a 747 goes overhead at 25000' its TCAS will flag me as a potential target as it doesn't know that I'm 23500 feet below. Correct??
So this system is of absolutely no use to me at all and is only for the benefit of IFR traffic.
So how about getting Mr Boeing or Mr Airbus to pay for it?
We need to have Mode S transponders - with height readout, (I thought that was Mode C), so that TCAS will function properly.
At the moment, if I'm down at 1500' with my transponder on and a 747 goes overhead at 25000' its TCAS will flag me as a potential target as it doesn't know that I'm 23500 feet below. Correct??
So this system is of absolutely no use to me at all and is only for the benefit of IFR traffic.
So how about getting Mr Boeing or Mr Airbus to pay for it?
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Some of the "rationale" (is that the correct word?) behind Mode S can be found here:
http://www.ais.org.uk/aes/pubs/aip/pdf/aic/4Y065.PDF
Of course, because this is secret you will have to log in to read it
http://www.ais.org.uk/aes/pubs/aip/pdf/aic/4Y065.PDF
Of course, because this is secret you will have to log in to read it
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Rustle, my comment about maybe having to stop squawking in some areas was based on what happens now (allegedly) in Holland, as I quoted above:
"The ironical thing is it is MOST STRICTLY FORBIDDEN to squawk below the schiphol tma........? "
WHC, TCAS works with Mode C. I have read elsewhere that the TCAS unit in an airliner (say) scans 30 degrees above and below. If true, it won't "see" you when you are 23500 feet below except when you are too far away to cause an "advisory" (instruction to the airliner to take avoiding action).
We could do with some expert posting up just what Mode S brings extra to the party. My understanding is that it would carry info additional to position (Mode A) and height (Mode C) such as registration, make and operator of airliner, whether they need extra baggage handlers or have had a medical emergency and need a midwife or a doctor, etc. - none relevant to TCAS.
For gliders I suspect it would just transmit that "this is a glider", and possibly the serial number of the transponder and the fact that the glider does not itself have TCAS so won't be telling the glider pilot anything to resolve a potential conflict, leaving it all to the airliner (or whatever) to do that.
"The ironical thing is it is MOST STRICTLY FORBIDDEN to squawk below the schiphol tma........? "
WHC, TCAS works with Mode C. I have read elsewhere that the TCAS unit in an airliner (say) scans 30 degrees above and below. If true, it won't "see" you when you are 23500 feet below except when you are too far away to cause an "advisory" (instruction to the airliner to take avoiding action).
We could do with some expert posting up just what Mode S brings extra to the party. My understanding is that it would carry info additional to position (Mode A) and height (Mode C) such as registration, make and operator of airliner, whether they need extra baggage handlers or have had a medical emergency and need a midwife or a doctor, etc. - none relevant to TCAS.
For gliders I suspect it would just transmit that "this is a glider", and possibly the serial number of the transponder and the fact that the glider does not itself have TCAS so won't be telling the glider pilot anything to resolve a potential conflict, leaving it all to the airliner (or whatever) to do that.
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Elementary mode 'S' is due to become live in certain parts of Europe from March 2003 but not the UK who is going straight to enhanced mode S in 2005.
A mode S transponder can be configured to transmit aircraft information including the maximum ceiling, maximum climb performance , aircraft type, flap position etc. This is then interfaced to the TCAS, which in the event of both aircraft having TCAS will determine which aircraft climbs and which descends.
Mode C considered to be a poor mans TCAS as the TCAS equipped aircraft will always get the avoidance manourve.
There has been reports in CHIRP of helicopters flying in the London airports area (Heathrow low level corridor I think) that have just been operating Mode A and as there was no altitude transmission, the TCAS has been giving Traffic alerts while on final.
To me as an engineer, the more info that aircraft can pass between each others avionic boxes the safer things will be, then again I'm biased and trying to keep in employment!!!!
Back in the real (to me) GA world, the cost would be extortionate.
A mode S transponder can be configured to transmit aircraft information including the maximum ceiling, maximum climb performance , aircraft type, flap position etc. This is then interfaced to the TCAS, which in the event of both aircraft having TCAS will determine which aircraft climbs and which descends.
Mode C considered to be a poor mans TCAS as the TCAS equipped aircraft will always get the avoidance manourve.
There has been reports in CHIRP of helicopters flying in the London airports area (Heathrow low level corridor I think) that have just been operating Mode A and as there was no altitude transmission, the TCAS has been giving Traffic alerts while on final.
To me as an engineer, the more info that aircraft can pass between each others avionic boxes the safer things will be, then again I'm biased and trying to keep in employment!!!!
Back in the real (to me) GA world, the cost would be extortionate.
Why do it if it's not fun?
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NigD2, if a mode-C equipped aircraft gets too close to a TCAS-equipped aircraft, the TCAS will not give either party any avoidance instructions.
It will tell the pilot of the TCAS-equipped aircraft that you're there. But, unless both parties have Mode S, neither will receive any instructions. Unless you have Mode S, the other aircraft doesn't know what you're doing, so it's not able to give avoidance advice.
FFF
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It will tell the pilot of the TCAS-equipped aircraft that you're there. But, unless both parties have Mode S, neither will receive any instructions. Unless you have Mode S, the other aircraft doesn't know what you're doing, so it's not able to give avoidance advice.
FFF
----------
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But it gets funnier and funnier - so long as you don't have to actually pay for these things.
The CAA have just issued 'consultation' requiring all Public Transport Category aircraft - regardless of use - to carry Mode C transponders. The legislative impact assessment is pretty short and strangely seems to have ignored the fact that these nice new boxes, costing over £2.5k by the time they are fitted will have to be thrown away within 4 years!!!
Am I missing something or is the CAA trying to clear UK airspace of those bothersome little things to give free rein for Public Transport aircraft over 5700 kg?
The CAA have just issued 'consultation' requiring all Public Transport Category aircraft - regardless of use - to carry Mode C transponders. The legislative impact assessment is pretty short and strangely seems to have ignored the fact that these nice new boxes, costing over £2.5k by the time they are fitted will have to be thrown away within 4 years!!!
Am I missing something or is the CAA trying to clear UK airspace of those bothersome little things to give free rein for Public Transport aircraft over 5700 kg?
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A good idea...in theory....if the boxes were provided by the EU. Yet again, the UK / European GA user is going to get shafted.
Maybe they ["Eurogovernement"] could spend less time discussing the number of ° in a banana's bend to allow it to be called a bananna and UK chocolate vs Beligum chocolate, and use some of the cost savings to send every aircraft owner in Europe a Mode-S box.
Why not make it like when cars had to have catalytic converters fitted? Old cars were excempt, but new cars after a certain date had to have them fitted.
Rgds
EA
Maybe they ["Eurogovernement"] could spend less time discussing the number of ° in a banana's bend to allow it to be called a bananna and UK chocolate vs Beligum chocolate, and use some of the cost savings to send every aircraft owner in Europe a Mode-S box.
Why not make it like when cars had to have catalytic converters fitted? Old cars were excempt, but new cars after a certain date had to have them fitted.
Rgds
EA
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chrisN
"Rustle, my comment about maybe having to stop squawking in some areas was based on what happens now (allegedly) in Holland, as I quoted above"
I know, but Mode S kit cannot be switched off - sorry I didn't explain that very well
Now a cynic might suggest that one of the drivers here is to enable a mechanism for charging (via Eurocontrol/NATS) for flights in "designated" airspace (read anywhere)
Before you laugh, we have a precedent:
Night flight in Class 'G' in a > 2 tonne aircraft when all the LARS have gone home
"Rustle, my comment about maybe having to stop squawking in some areas was based on what happens now (allegedly) in Holland, as I quoted above"
I know, but Mode S kit cannot be switched off - sorry I didn't explain that very well
Now a cynic might suggest that one of the drivers here is to enable a mechanism for charging (via Eurocontrol/NATS) for flights in "designated" airspace (read anywhere)
Before you laugh, we have a precedent:
Night flight in Class 'G' in a > 2 tonne aircraft when all the LARS have gone home
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Joe operates from her privately owned strip in the South of England and his friend is based at L2K. They regularly fly cross channel to meet up. Both have just spent 4,000 euros on a mode S box because someone in Brussels said they must. They didn’t realise it cost another 1,500 euros to have it fitted. Joe found nobody wanted her three year old mode C transponder which was perfectly serviceable, and Pierre had to reorganise his panel because he had not had a transponder fitted before, which cost him another 500 euros.
Joe set off in reasonable visibility, but by the time she got to Dungeness visibility had deteriorated. She had an IMC but knew at the FIR boundary her vanilla PPL would be her only license privileges. She thought she would try Manston for a LARS, but was beneath and beyond their cover. London info had her details, but also could not provide a radar service – they were sorry. Pierre was a bit more fortunate because Lille gave him a radar information service – he was pleased he had the box for 10 minutes until he got to the FIR boundary.
Both were now with London info and both were “surrounded” by the L2K day trippers. London info was manfully coping with all the different position reports, and generally pilots were altering altitude to avoid conflict. Unfortunately both Pierre and Joe altered for another aircraft and ended up on reciprocal headings at the same level. Fortunately they missed, but only just.
Joe and Pierre each fly around 100 hours a year. Joe operates occasionally within CAS, but spends most of her time in Northern France or Southern England were it is easy to avoid CAS. Pierre’s bi-plain is a beautiful old girl – his new mode s box is the only new bit of kit he has fitted in the last twenty years. Other than his cross channel sorties he potters around northern France. Most of the time he is lucky to get a flight information service never mind a RAS, but they told him he must fit the box.
They both wonder whether their shiny new box was worth the price.
Joe set off in reasonable visibility, but by the time she got to Dungeness visibility had deteriorated. She had an IMC but knew at the FIR boundary her vanilla PPL would be her only license privileges. She thought she would try Manston for a LARS, but was beneath and beyond their cover. London info had her details, but also could not provide a radar service – they were sorry. Pierre was a bit more fortunate because Lille gave him a radar information service – he was pleased he had the box for 10 minutes until he got to the FIR boundary.
Both were now with London info and both were “surrounded” by the L2K day trippers. London info was manfully coping with all the different position reports, and generally pilots were altering altitude to avoid conflict. Unfortunately both Pierre and Joe altered for another aircraft and ended up on reciprocal headings at the same level. Fortunately they missed, but only just.
Joe and Pierre each fly around 100 hours a year. Joe operates occasionally within CAS, but spends most of her time in Northern France or Southern England were it is easy to avoid CAS. Pierre’s bi-plain is a beautiful old girl – his new mode s box is the only new bit of kit he has fitted in the last twenty years. Other than his cross channel sorties he potters around northern France. Most of the time he is lucky to get a flight information service never mind a RAS, but they told him he must fit the box.
They both wonder whether their shiny new box was worth the price.
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Seeking to make an intelligent comment to the CAA, I posted a question on the ATC forum asking for their input as to how they may be adversely affected if GA (light) were given an exemption or partial exemption from the Mode S regulations.
After all it would be difficult to protest if there were significant safety issues.
So far zero responses.
From what has since been posted on this forum am I right in concluding that there are no significant safety issues?
After all it would be difficult to protest if there were significant safety issues.
So far zero responses.
From what has since been posted on this forum am I right in concluding that there are no significant safety issues?
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Just a quick read, the 'consultative document' suggests four options. Option 1 is do nothing, all the way to Option 4 which is
Funny, but to my reading of the doc the decision has already been made (Option 3), so I wonder what is 'consultative' about it. Maybe I am being cynical.
I think in order to get cheap kit, you need a massive market. I hate to harp on about it, but that means waiting for the US to decide what to do, and then you will get a massive economy of scale. Although Mode S groundstations are alive and kicking all over the US, I get the impression the US has decided to pass by Mode S for GA and is getting into true 'consultation' with the GA community with regard to ADS-B, Option four in the CAA doc.
(And don't get too excited, that's the FAA talking)
So it would be a real bummer if you had to purchase and install Mode S kit, then the world moves to ADS-B, and you had to go out and buy some more new kit!
Option 4. Await the maturity of alternative technologies to Mode S SSR, such as ‘Automatic Dependent Surveillance – Broadcast (ADS-B)’, and implement them at a later date.
I think in order to get cheap kit, you need a massive market. I hate to harp on about it, but that means waiting for the US to decide what to do, and then you will get a massive economy of scale. Although Mode S groundstations are alive and kicking all over the US, I get the impression the US has decided to pass by Mode S for GA and is getting into true 'consultation' with the GA community with regard to ADS-B, Option four in the CAA doc.
Since ADS-B is a "cooperative" surveillance technique and 96% of the civil aircraft operating in the national airspace system are "general aviation" aircraft, the affordability of ADS-B is crucial to its success.
So it would be a real bummer if you had to purchase and install Mode S kit, then the world moves to ADS-B, and you had to go out and buy some more new kit!
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bluskis:
Mode S has been debated on the ATC forum several times. This may be why you are having a slow response.
Last thread I read seemed to conclude that there was little benefit for ATC in having GA outside controlled airspace squawking mode S. If all flying machines so squawked, the radar screens would be so overloaded that they would have to filter-out the squawks of no interest. I believe the TMA controllers (and some airways) filter out 7000 squawks now.
Why not do a search and you will see what I mean?
Mode S has been debated on the ATC forum several times. This may be why you are having a slow response.
Last thread I read seemed to conclude that there was little benefit for ATC in having GA outside controlled airspace squawking mode S. If all flying machines so squawked, the radar screens would be so overloaded that they would have to filter-out the squawks of no interest. I believe the TMA controllers (and some airways) filter out 7000 squawks now.
Why not do a search and you will see what I mean?