Mid air over Hertfordshire
So, anyway, does anyone object to the idea of dedicated A/A freq's for the n/s London lanes? If so I would be interested to understand that argument.
ADS-B is a great idea, but its not going to solve the problem of the congested lanes... but as implemented in the Alaskan Capstone programme it requires a data-link radio and GPS to be fitted to aircraft as well as other expensive displays etc (ref. http://www.alaska.faa.gov/capstone/...s/slide0223.htm)so you might be barking up the wrong tree there if your goal is to avoid the cost of a transponder!?
It's more that likely that ADS-B will be implemented using Mode S extended squitter in Europe as everything with an electrical system will have to have a Mode S transponder from 2008. But for the lighter stuff, I do believe that UAT provides a valid alternative that would allow a higher proportion of equippage than Mode S.
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You may have marked me down as a detracter. The blind calls idea has many merits but also has failings. I feel that the benefits should not be ignored and would like to see it used, or certainly trialled.
I'm not sure we can really get this any further, without the outcome of the AAIB report. We are all talking about avoiding each other when straight and level, transiting a known choke point. At least one of these two aircraft was not straight and level and at least one was not transitting the choke point.
This CAA Safety Leaflet may be helpful to some. Its always surprised me that the narrow VFR routes around the M25/Lea Valley crossing point (the most congested bit in my experience) are bi-directional!!
bs
You may have marked me down as a detracter. The blind calls idea has many merits but also has failings. I feel that the benefits should not be ignored and would like to see it used, or certainly trialled.
I'm not sure we can really get this any further, without the outcome of the AAIB report. We are all talking about avoiding each other when straight and level, transiting a known choke point. At least one of these two aircraft was not straight and level and at least one was not transitting the choke point.
This CAA Safety Leaflet may be helpful to some. Its always surprised me that the narrow VFR routes around the M25/Lea Valley crossing point (the most congested bit in my experience) are bi-directional!!
bs
The Original Whirly
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I actually suggested the blind calls idea. I thought it was a good idea, and so did several people I ran it by at the PFA Rally. So I suggested it to David Cockburn of the CAA at the Rally (BTW, he probably reads this thread; he knows who I am, and always seems to know what I've said!!!). He pointed out that aircraft flying in and out of Elstree, Denham, Panshangar, Stapleford, and North Weald are all talking to the relevant airfields...so would yet another frequency help? He suggested people transiting that area talk to the airfields concerned, and London Information in between times. Now, I didn't say it at the time (didn't think, sorry) but as a single pilot with one radio, changing frequencies that often is head inside cockpit for far too long for my liking. And I agree that expensive electronic gizmos are...well, too expensive. so, back to the drawing board...
What about...
Aircraft going in and out of said airfields, not above 1000 ft. Aircraft transiting that corridor going west, 1500 ft. Aircraft going east, 2000 ft. And something similar for the Manchester low level route, though it would have to be, say, 900 ft, and 1200 ft.
Probably a snag, but haven't thought of it yet. I'm just trying to think of a cheap, simple idea that might work.
What about...
Aircraft going in and out of said airfields, not above 1000 ft. Aircraft transiting that corridor going west, 1500 ft. Aircraft going east, 2000 ft. And something similar for the Manchester low level route, though it would have to be, say, 900 ft, and 1200 ft.
Probably a snag, but haven't thought of it yet. I'm just trying to think of a cheap, simple idea that might work.
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Sounds like an elaborate scheme in response to a recent regrettable but vanishingly rare occurence.
Putting lots of aircaft in the same airspace at the same altitude worsens, rather than improves the current position.
2D
Putting lots of aircaft in the same airspace at the same altitude worsens, rather than improves the current position.
2D
Avoid imitations
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The problem with giving altitude bands according to direction is that ATC will sometimes need aircraft at a different altitude. For example, AlanM and his colleagues usually want helicopters joining the London Zone via a Special VFR Clearance at 1500 feet by the boundary of Class A. This applies whichever direction the aircraft is joining from. I'm sure the local residents will soon be up in arms if every aircraft joining the local airfields flies at 1000 feet, there is a noise problem at all of them already.
The other idea of blind calls is a sensible one but the calls may not be heard by all traffic, bearing in mind that the choke points are about 25 miles in length and it takes quite a while for aircraft to transit the area. It would require all pilots to keep repeating the calls to make sure everyone is aware and this may cause saturation of the frequency. As AlanM said, there will still be other aircraft on a Radar service, possibly IMC, on a different frequency but in the same airspace.
Heathrow, Luton, City and Stansted do a very good job between them but I'm sure they don't want all aircraft on their frequency. A dedicated ATC service IS probably the only real answer.
Rather than the present bi-directional routes at the NE corner, what about using the BPK and LAM beacons like road roundabouts? Traffic only being allowed to fly past them clockwise. To give separation on a/c flying through the space between these two beacons, all pilots could fly within a maximum range of 4nm from the BPK when going south through the gap and aircraft going north no more than 5nm from LAM. With the very obvious water feature between the two beacons, that also means the right hand rule would be complied with. Publish that on the CAA charts instead.
Just to set the cat amongst the pigeons, how about making Mode C mandatory for aircraft transitting under the London TMA unless able to obtain at least a Radar Information service?
The other idea of blind calls is a sensible one but the calls may not be heard by all traffic, bearing in mind that the choke points are about 25 miles in length and it takes quite a while for aircraft to transit the area. It would require all pilots to keep repeating the calls to make sure everyone is aware and this may cause saturation of the frequency. As AlanM said, there will still be other aircraft on a Radar service, possibly IMC, on a different frequency but in the same airspace.
Heathrow, Luton, City and Stansted do a very good job between them but I'm sure they don't want all aircraft on their frequency. A dedicated ATC service IS probably the only real answer.
Rather than the present bi-directional routes at the NE corner, what about using the BPK and LAM beacons like road roundabouts? Traffic only being allowed to fly past them clockwise. To give separation on a/c flying through the space between these two beacons, all pilots could fly within a maximum range of 4nm from the BPK when going south through the gap and aircraft going north no more than 5nm from LAM. With the very obvious water feature between the two beacons, that also means the right hand rule would be complied with. Publish that on the CAA charts instead.
Just to set the cat amongst the pigeons, how about making Mode C mandatory for aircraft transitting under the London TMA unless able to obtain at least a Radar Information service?
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How about having a dedicated transponder code which means 'I am VFR traffic keeping clear of controlled airspace' ?
At least that way the airline traffic wouldn't have to take action to avoid traffic several thousand feet below them.
At least that way the airline traffic wouldn't have to take action to avoid traffic several thousand feet below them.
Avoid imitations
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That's a good idea but it already exists. 7000
[Mode C completes the picture but then we're back where we started].
[Mode C completes the picture but then we're back where we started].
aceatco, retired
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TCAS doesn't decode and therefore differentiate what mode A code an aircraft has selected.
ATC ignore what radar returns (primary or secondary) are operating near or underneath CAS on the basis we assume they will stay outside. Only if positive info is received that someone is lost, or the mode C indicates someone might be inside, or there is a feeling in the water, do we take action.
ATC ignore what radar returns (primary or secondary) are operating near or underneath CAS on the basis we assume they will stay outside. Only if positive info is received that someone is lost, or the mode C indicates someone might be inside, or there is a feeling in the water, do we take action.
How about having a dedicated transponder code which means 'I am VFR traffic keeping clear of controlled airspace' ?
That's a good idea but it already exists. 7000
The Germans have two different VFR squawks according to whether the aircraft is above or below 5000 ft. I don't know if that was specifically designed to accommodate Mode A only aircraft.
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7000 is the conspicuity code. It does not imply VFR. I think Kolibear's idea is a good one. I'd adapt it slightly and suggest a different code for those flying IFR outside controlled airspace rather than VFR.
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On reflection, I'm going back to thinking a dedicated frequency and blind calls is the way to go; here's why...
1) A new LARS service, TCAS, Mode S etc - all too expensive; will never happen, and we wouldn't like it and couldn't afford it if it did.
2) present situation - everyone talks to London Info, Luton, Stansted, or the GA airfields...so no-one can actually hear all traffic. And have you ever tried to get hold of London Info on a sunny day when everyone's doing day trips to France..." Standby G-XXXX, you are No3..."
3) Blind calls could be fairly precise in that area; loads of ground features. While not compulsory, it could be strongly recommended. Like most things in aviation designed to keep you alive, really.
4) The objection that aircraft flying out of the GA airfields are talking to the airfields is not a problem. I fly out of Sleap, into crowded Shawbury MATZ. As soon as I leave the ATZ I talk to Shawbury. It works. Suggested typical call: "North London (or whatever we call it) Traffic, G-XXXX, C152, just departed from Elstree, presently at 1000 ft and climbing to 1800 ft....etc".
5) Even knowing where most of the traffic is could be helpful, better than not knowing where anyone is.
6) One frequency, no changing of frequencies, so eyes kept outside cockpit.
7) Cheap and easy to implement, and only requires aircraft to have a radio...a handheld will do.
CAA, if you're reading this, please have a think about it!
Lastly, the usual answer to complaints of the dangers of the Manchester LLR, and probably this North London area too, is that no accidents have occurred there, so it can't be a problem. Now, one has, and everyone says not to over-react...yes, I know I said it too, but I think SOMETHING needs to be done, just...not so much that we lose our freedom. I'm looking for a balance of safety and freedom. I think this would do it.
1) A new LARS service, TCAS, Mode S etc - all too expensive; will never happen, and we wouldn't like it and couldn't afford it if it did.
2) present situation - everyone talks to London Info, Luton, Stansted, or the GA airfields...so no-one can actually hear all traffic. And have you ever tried to get hold of London Info on a sunny day when everyone's doing day trips to France..." Standby G-XXXX, you are No3..."
3) Blind calls could be fairly precise in that area; loads of ground features. While not compulsory, it could be strongly recommended. Like most things in aviation designed to keep you alive, really.
4) The objection that aircraft flying out of the GA airfields are talking to the airfields is not a problem. I fly out of Sleap, into crowded Shawbury MATZ. As soon as I leave the ATZ I talk to Shawbury. It works. Suggested typical call: "North London (or whatever we call it) Traffic, G-XXXX, C152, just departed from Elstree, presently at 1000 ft and climbing to 1800 ft....etc".
5) Even knowing where most of the traffic is could be helpful, better than not knowing where anyone is.
6) One frequency, no changing of frequencies, so eyes kept outside cockpit.
7) Cheap and easy to implement, and only requires aircraft to have a radio...a handheld will do.
CAA, if you're reading this, please have a think about it!
Lastly, the usual answer to complaints of the dangers of the Manchester LLR, and probably this North London area too, is that no accidents have occurred there, so it can't be a problem. Now, one has, and everyone says not to over-react...yes, I know I said it too, but I think SOMETHING needs to be done, just...not so much that we lose our freedom. I'm looking for a balance of safety and freedom. I think this would do it.
Current situation:
The SE of Englands airspace is dangerously overcrowded. One day an airliner and a GA aircraft are going to have a collision which TCAS would have prevented.
In the aftermath we will see several things happen.
1) Public outrage. A mature simple technology costing only thousands of pounds was not fitted to the light aircraft.
2) Public demand for an enquiry by some Barrister or other which will be granted.
3) A series of recommendations that no Government will be able to ignore in case it happens again.
4) These will include a massive increase in CAS, mandatory ModeC + TCAS, 'improved' training for PPLs.
5) Don't worry about the cost of 4) as by the week after the mid-air the insurance industry reeling from a potential £750,000,000 claim will have withdrawn insurance on GA aircraft or if fitted with the kit still increased the premiums by 500%
-------
With this sword hanging above your heads don't you think the GA community ought to be doing something more proactive than insinuating they have better Mk1 eyeballs than us Autopilot junkies. Which you don't.
I still fly GA, was an instructor for over a decade and hope to buy a microlight and operate my own strip in the future.
I fly at 60tons 250kts in the open FIR from 10,000ft - 3,000ft most days of the week. 'Dodging' TCAS Mode A returns is a regular occurence. Just because its a world you don't know about doesn't mean it isn't happening.
Cheers
WWW
The SE of Englands airspace is dangerously overcrowded. One day an airliner and a GA aircraft are going to have a collision which TCAS would have prevented.
In the aftermath we will see several things happen.
1) Public outrage. A mature simple technology costing only thousands of pounds was not fitted to the light aircraft.
2) Public demand for an enquiry by some Barrister or other which will be granted.
3) A series of recommendations that no Government will be able to ignore in case it happens again.
4) These will include a massive increase in CAS, mandatory ModeC + TCAS, 'improved' training for PPLs.
5) Don't worry about the cost of 4) as by the week after the mid-air the insurance industry reeling from a potential £750,000,000 claim will have withdrawn insurance on GA aircraft or if fitted with the kit still increased the premiums by 500%
-------
With this sword hanging above your heads don't you think the GA community ought to be doing something more proactive than insinuating they have better Mk1 eyeballs than us Autopilot junkies. Which you don't.
I still fly GA, was an instructor for over a decade and hope to buy a microlight and operate my own strip in the future.
I fly at 60tons 250kts in the open FIR from 10,000ft - 3,000ft most days of the week. 'Dodging' TCAS Mode A returns is a regular occurence. Just because its a world you don't know about doesn't mean it isn't happening.
Cheers
WWW
[IFR conspicuity code] For what purpose?
If everyone has Mode C, I agree it's pretty pointless, as I'll believe the encoder's assessment of the altitude over the pilot's assessment of flight conditions any day.
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www
That is a fairly apocalyptic view. What sort of GA type would that be?
If the airliner were to hit me, it would have the same effect as if it had hit a bird. They might wonder why there was a bit of a thud, but that would be all. Bit different for me though
As I go nowhere near where airliners fly - they won't let me near them on my licence and aircraft type - I don't see I'm that much of a problem to them.
I'm much more worried about being hit by the military who operate on UHS not on our frequencies.
I have no wish to be blown out of the sky by anyone, and my sense of self-preservation means I'm always looking around (electronically as well as Mk1 eyeball)
When I am gliding, esp xcountry, power should give way to me, but I'm coward enough not to stand on my rights - I don't assume the pilot even knows I'm there and 99% of the time I'm right - they are head down in the cockpit as I give him a 'friendly' wave.
That is a fairly apocalyptic view. What sort of GA type would that be?
If the airliner were to hit me, it would have the same effect as if it had hit a bird. They might wonder why there was a bit of a thud, but that would be all. Bit different for me though
As I go nowhere near where airliners fly - they won't let me near them on my licence and aircraft type - I don't see I'm that much of a problem to them.
I'm much more worried about being hit by the military who operate on UHS not on our frequencies.
I have no wish to be blown out of the sky by anyone, and my sense of self-preservation means I'm always looking around (electronically as well as Mk1 eyeball)
When I am gliding, esp xcountry, power should give way to me, but I'm coward enough not to stand on my rights - I don't assume the pilot even knows I'm there and 99% of the time I'm right - they are head down in the cockpit as I give him a 'friendly' wave.
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They might wonder why there was a bit of a thud, but that would be all.
See this case: 727 vs Cessna
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robin,
www does have a point, he just needs to think things through a bit more. A large transport jet went down over San Diego after a collision with a C172. As predicted by www, questions were asked, changes were made to airspace and mandatory transponder use in certain places, and GA still flourishes in the US in a way the Brits can only dream of.
I think it's reasonable for TCAS to have situational awareness of any nearby GA aircraft, and GA pilots should help out with this. We all fly in the back of 737s and I don't want the pilots to be performing aerobatics either, if only because they might be uncoordinated and I will spill my Gin and Tonic
Mode S is not the answer though.
Is SE England airspace really 'dangerously' overcrowded? Should I be scared to get into a jet out of Heathrow? I know the check in areas are overcrowded and some people look like they might punch me, and it takes an age to get onto stand sometimes, but the air looks remarkably empty compared to places like NY and LA. In both those places all traffic (with waivers for a few) has to have mode C, and ATC have the resources and desire to provide radar services to all.
www does have a point, he just needs to think things through a bit more. A large transport jet went down over San Diego after a collision with a C172. As predicted by www, questions were asked, changes were made to airspace and mandatory transponder use in certain places, and GA still flourishes in the US in a way the Brits can only dream of.
I think it's reasonable for TCAS to have situational awareness of any nearby GA aircraft, and GA pilots should help out with this. We all fly in the back of 737s and I don't want the pilots to be performing aerobatics either, if only because they might be uncoordinated and I will spill my Gin and Tonic
Mode S is not the answer though.
Is SE England airspace really 'dangerously' overcrowded? Should I be scared to get into a jet out of Heathrow? I know the check in areas are overcrowded and some people look like they might punch me, and it takes an age to get onto stand sometimes, but the air looks remarkably empty compared to places like NY and LA. In both those places all traffic (with waivers for a few) has to have mode C, and ATC have the resources and desire to provide radar services to all.
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If the airliner were to hit me, it would have the same effect as if it had hit a bird.
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With regard to XPDR codes, how about a dedicating the last two/three digits to altitude(regional/fligh level?) e.g flying at 3500' squawk 7035, or an aircraft at 12500' will squawk 7125. I don't know too many people who fly at 50000, 60000 and 70000, so it shouldn't conflict with the emergency squawks. It's not perfect, but it will eliminate the need for a upgrade from Mode A to C. While it might be of no use to TCAS equiped aircraft, i think the scope-jockeys
will appreciate it.
Robin,
like most private flyers you wrongly assume that airliners don't fly in class G. I suggest you speak to a controller at one of the increasing number of regional airports in the UK, you're in for a shock. For example, thomsponfly as well as a lot of bizjets operate out of Coventry. The ILS 23 approach to coventry starts for DTY at 2500 (yes, 2500) ft flying northward in class g airspace to intercept the localiser at 1700ft. Airliners flying into east midlands are routinely vectored out of CAS. I live near East mids but not under their CTA, and quite often i look up at an airliner and think "he's a bit low isn't he?"
Like you I used to look up at the contrails high up and feel safe, until i saw an airliner fly over my local airfield at no more than 3000ft.
Capt M
will appreciate it.Robin,
like most private flyers you wrongly assume that airliners don't fly in class G. I suggest you speak to a controller at one of the increasing number of regional airports in the UK, you're in for a shock. For example, thomsponfly as well as a lot of bizjets operate out of Coventry. The ILS 23 approach to coventry starts for DTY at 2500 (yes, 2500) ft flying northward in class g airspace to intercept the localiser at 1700ft. Airliners flying into east midlands are routinely vectored out of CAS. I live near East mids but not under their CTA, and quite often i look up at an airliner and think "he's a bit low isn't he?"
Like you I used to look up at the contrails high up and feel safe, until i saw an airliner fly over my local airfield at no more than 3000ft.
Capt M