Thoughts on reducing risk of mid-airs.
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Technology is not a substitute, or shouldn't be. It supplements and enhances the effectiveness of see and avoid, and is itself improving.
Is there a technique thats adequate to stay out of mid-airs - with say, all-white aircraft, no flarm, no P/TCAS, no transponder, no ATC service, not using radio - that couldn't be meaningfully supplemented?
Is there a technique thats adequate to stay out of mid-airs - with say, all-white aircraft, no flarm, no P/TCAS, no transponder, no ATC service, not using radio - that couldn't be meaningfully supplemented?
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BTW, I question the contributor who reckons greatest risk of collision is in the circuit: with everyone going the same direction, with the same intention and on the same frequency, all these factors reduce collision risk.
Why that is so is an interesting question IMHO, bearing in mind the factors you mention... One interpretation is that the main collision avoidance mechanism is the big sky concept, and where that does not apply (=traffic pattern) the risk of collisions goes up tremendously, despite same direction frequency intention etc.
This is a pretty interesting publication on the subject: http://www.aopa.org/asf/publications/sa15.pdf
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Is there something intrinsically wrong with the RAF Grob having the PIC in the right hand seat and wearing a bone dome scanning to port must be difficult if not impossible.....
I recall that in the USA about 25/30 years ago they did a statistical analysis of mid air collisions and very close airproxes.
The highest risk was if you were within 10 nm of an airport with mixed VFR/IFR traffic - very often these airports were equipped with radar. In the open FIR there tends to be a fair amount of random separation built in (apart from certain choke points) so although you might get a fright by having an airprox the chances of a midair collision are relatively low.
I often call Class G "jungle airspace". To many airspace users (including me!) the idea of a control service in the open FIR is something of an anethma. There are ways of sensibly mitigating the risks many of which have been mentioned in this thread.
A question I sometimes ask students and pilots is if you have to go around from an approach what is the first action? Very rarely, if ever, is lookout (above) mentioned. Also my observation is that very often the lookout below prior to descent is omitted. Do you weave during climb and descents? This is very basic stuff and whilst the mk 1 eyeball isn't infallible correct lookout techniques are vital to remain safe.
The highest risk was if you were within 10 nm of an airport with mixed VFR/IFR traffic - very often these airports were equipped with radar. In the open FIR there tends to be a fair amount of random separation built in (apart from certain choke points) so although you might get a fright by having an airprox the chances of a midair collision are relatively low.
I often call Class G "jungle airspace". To many airspace users (including me!) the idea of a control service in the open FIR is something of an anethma. There are ways of sensibly mitigating the risks many of which have been mentioned in this thread.
A question I sometimes ask students and pilots is if you have to go around from an approach what is the first action? Very rarely, if ever, is lookout (above) mentioned. Also my observation is that very often the lookout below prior to descent is omitted. Do you weave during climb and descents? This is very basic stuff and whilst the mk 1 eyeball isn't infallible correct lookout techniques are vital to remain safe.
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Good for him, any idea of his route?
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Technology is no substitute for technique
The best one can do is play the probabilities in one's favour.
The "Mk 1 eyeball" so beloved of the proverbial ex RAF navigators who write the training literature, doesn't work, and never did work. Not in cases where there is a genuine collision course.
Fortunately, due to the way flying is trained, it is not too hard to improve matters drastically.
Flying well above 1000ft, say 3000ft, reduces the probability more than anything else - by at least an order of magnitude. So much so that there have been no UK midairs (TMK) above 2000ft - ever.
Flying at weird levels, say 2300 or 2700 or 3300ft, reduces it by another huge amount - because most people who fly "high" fly as they have been trained i.e. at 2000ft 2500ft or 3000ft.
Be conscious of aerodrome circuits when flying enroute. Get a decent GPS which shows the ATZs and even when flying an accurate planned route, give these areas a wide margin. Another order of magnitude improvement?
If you have to fly low, e.g. taking pics of your bird's house, or departing or arriving, have all the lights on. One is far more visible in a near head-on situation when the landing light is on, even during bright sunlight.
TCAS would be great but until Mode C is made mandatory it will be of limited usefulness for avoiding actually possible collisions, versus the cost of the proper active system - £10k+. And I suspect a huge % of the low level bimblers don't have a transponder or don't switch it on, anyway, and if you fly high, there ain't nobody there, more or less.
Personally, I don't worry about this.
The circuit remains the dangerous place. The only time I do overhead joins is when ordered by ATC. At AFIS or A/G airfields I ignore the "overhead RH circuit" default instruction and if he reports no known traffic I tell him I will report downwind / crosswind / long final. But I must confess I wouldn't fly to Stapleford (or some other totally mad free for all place where people cut you up left right and middle) on a sunny Sunday
If you have an autopilot, use it to reduce cockpit workload and look out of the window - one day you might actually spot something.
If you have a GPS, use it to reduce cockpit workload and look out of the window - as above.
But don't bank on spotting the one that might get you while flying at 1000ft.
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TCAS would be great but until Mode C is made mandatory it will be of limited usefulness for avoiding actually possible collisions, versus the cost of the proper active system - £10k+. And I suspect a huge % of the low level bimblers don't have a transponder or don't switch it on, anyway, and if you fly high, there ain't nobody there, more or less.
I think that is the one aspect of your post with which I disagree, although I havent got any proven stats with which to back it up.
Using TAS I reckon that only around 10% of primary contacts reported by PR is not shown on TAS, and about 5% are shown with no height information. That would suggest that most traffic has transponders at a mix of levels - albeit I agree the number without is even less at higher levels.
It would be interesting to know what % of the UK GA fleet has a transponder fitted - does anyone know?
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Using TAS I reckon that only around 10% of primary contacts reported by PR is not shown on TAS, and about 5% are shown with no height information. That would suggest that most traffic has transponders at a mix of levels - albeit I agree the number without is even less at higher levels.
These contacts would not usefully show on any TCAS system.
I think Mode C fit % is close to 100% among those flying higher up, say 3000ft+. It's a whole different pilot population up there.
Between flying below 2000ft, and flying above 3000ft (approx) it seems as if GA exists in two different compartments.
A lot of pilots joke about getting a nosebleed at a few thousand feet but I don't think many of them are actually joking.
Avoid imitations
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Tinpilot,
Thankyou. That was probably the glider I passed yesterday.
I asked the question because after what I think was about 7.5 hours flying he still had enough electrical power to speak to an ATC radar unit and to use a transponder with mode C, which helped us to see and avoid him, using our TCAS to assist our lookout.
Good on him, a good example of how to fly in a thoroughly professional manner, he allowed us the chance to avoid his aircraft by changing our transit altitude in good time and keep us all the safer for it, whilst maintaining my passengers' comfort.
Thankyou. That was probably the glider I passed yesterday.
I asked the question because after what I think was about 7.5 hours flying he still had enough electrical power to speak to an ATC radar unit and to use a transponder with mode C, which helped us to see and avoid him, using our TCAS to assist our lookout.
Good on him, a good example of how to fly in a thoroughly professional manner, he allowed us the chance to avoid his aircraft by changing our transit altitude in good time and keep us all the safer for it, whilst maintaining my passengers' comfort.
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From the link posted by somebody above, it shows it is an ASH25 EB28 – a 2-seat motor glider (fold-away engine) which has much bigger battery capacity than most gliders. “Electric power supply by two lead batteries, one in each inner wing. . . . 5 kg can be saved by using lithium-mangan-batteries in the fuselage instead of lead batteries in the inner wings.” [Sic]
See: Binder aircraft- & engineconstruction | ASH 25 EB 28 | ASH 25 EB 28 for details if interested.
For the umpteenth time, yes, SOME gliders can have transponders, and SOME of those have fitted them. SOME OTHERS, like mine could physically have a transponder, but EASA at present prevents it.
AND A LOT OF GLIDERS cannot and never will have.
I can’t really believe ST does not understand, but I don’t know why he keeps hammering the point that SOME gliders have transponders, as if that means all could.
If I got a needle stuck in a groove saying SOME powered aircraft have BRS, TCAS, Autopilot, and two crew to look out, so all can, so why don’t you all do it - I suspect that he and others would soon get fed up.
As I am of having to remind people who keep hammering that some gliders can have transponders as if that means that all can.
And two transponding gliders have no communication to tell each other of impending collision – only ST etc. with TCAS, or those who also fit PCAS, could know. Flarm is better than that for glider/glider. It could be used for GA/glider. Why don’t they get Flarm as well as their other equipment?
Chris N.
See: Binder aircraft- & engineconstruction | ASH 25 EB 28 | ASH 25 EB 28 for details if interested.
For the umpteenth time, yes, SOME gliders can have transponders, and SOME of those have fitted them. SOME OTHERS, like mine could physically have a transponder, but EASA at present prevents it.
AND A LOT OF GLIDERS cannot and never will have.
I can’t really believe ST does not understand, but I don’t know why he keeps hammering the point that SOME gliders have transponders, as if that means all could.
If I got a needle stuck in a groove saying SOME powered aircraft have BRS, TCAS, Autopilot, and two crew to look out, so all can, so why don’t you all do it - I suspect that he and others would soon get fed up.
As I am of having to remind people who keep hammering that some gliders can have transponders as if that means that all can.
And two transponding gliders have no communication to tell each other of impending collision – only ST etc. with TCAS, or those who also fit PCAS, could know. Flarm is better than that for glider/glider. It could be used for GA/glider. Why don’t they get Flarm as well as their other equipment?
Chris N.
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Forgive me if this has been mentioned previously.
It is not only the lookout that is important but the eyes need to be focused. It is of little use being on instruments for a period of time and then proceed to lookout for something several miles away from your aircraft. Your eyes need to be focused for that distance, for you to see effectively. This takes time and not 5 seconds or so.
To focus you need to look at an object of that approximate distance, not just thin air.
This may sound like a wise guy statement but if you want to avoid completely the risk of a mid air collision, then stay on the ground. Mind you the aluminium /composite show will probably get you, from some other persons bad day at the office.
It is not only the lookout that is important but the eyes need to be focused. It is of little use being on instruments for a period of time and then proceed to lookout for something several miles away from your aircraft. Your eyes need to be focused for that distance, for you to see effectively. This takes time and not 5 seconds or so.
To focus you need to look at an object of that approximate distance, not just thin air.
This may sound like a wise guy statement but if you want to avoid completely the risk of a mid air collision, then stay on the ground. Mind you the aluminium /composite show will probably get you, from some other persons bad day at the office.
Last edited by joehunt; 17th Jun 2009 at 07:25.
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IO and others.
the idea that there is a lot less traffic at say 3000'+ can be a questionable assumption. This may be true of powered light aircraft but on a thermic day the gliders will operating as high as they can keep themselves. ie from cloudbase to 1000 - 1500 feet below cloudbase. So if it's a 5000' cloudbase day, there will be a lot of gliders in the 4000' band, particularly through the known choke points.
Sad to say Didcot/Abingdon is one of the said choke points
the idea that there is a lot less traffic at say 3000'+ can be a questionable assumption. This may be true of powered light aircraft but on a thermic day the gliders will operating as high as they can keep themselves. ie from cloudbase to 1000 - 1500 feet below cloudbase. So if it's a 5000' cloudbase day, there will be a lot of gliders in the 4000' band, particularly through the known choke points.
Sad to say Didcot/Abingdon is one of the said choke points
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For the umpteenth time, yes, SOME gliders can have transponders, and SOME of those have fitted them. SOME OTHERS, like mine could physically have a transponder, but EASA at present prevents it.
AND A LOT OF GLIDERS cannot and never will have.
I can’t really believe ST does not understand, but I don’t know why he keeps hammering the point that SOME gliders have transponders, as if that means all could.
AND A LOT OF GLIDERS cannot and never will have.
I can’t really believe ST does not understand, but I don’t know why he keeps hammering the point that SOME gliders have transponders, as if that means all could.
The ones who want to fly in cloud should be equipt to a certain standard and their pilots should be trained to a glider pilot specific IMCR.
In VMC we fly see and avoid in clouds we cannot. In powered flight there are rules as to who can or cannot operate in clouds. As an ATP I could go out and buy myself A Europa. I could build it, spend a fortune on avionics. Would the CAA allow me to fly it in clouds? NO. Could I argue that gliders have exceptions so why not me?
On the other hand as a glider pilot I can buy an old wreck of a glider with minimal instrument flying instrumentation. I can have NO radio, little IMC flying experience and I can fly blind to all in clouds to my hearts content.
Is that a level playing field between power and gliders? is that fair morally never mind from a safety aspect?
Because see and avoid is a non starter in cloud flying there should be regulations to stop aircraft and pilots who are not equipt to be there from being there.
Like the example of the Europa in powered flight if the glider cannot meet the required standards and the same with the pilot it should be legally limited to day VMC ONLY. There is no valid or fair arguement for otherwise.
There is a fair arguement that gliders cannot fly normal VFR rules. To force them to do so would destroy the sport. We as power pilots know gliders maybe lurking in cloudbases so to be allowed to fly to glider specific VFR rules maybe FLARM should be looked at for all gliders.
Flarm is a good option for VMC gliders and an extra backup for IMC gliders but unless regulated as a requirement for all powered and non powered it can give a false sense of security.
Pace
Last edited by Pace; 17th Jun 2009 at 08:07.
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IO540
With all your experience you must have noticed that some VFR pilots are very good at spotting other traffic and some are not. The more one works on lookout and scan the better ones gets, but it is not 100% and never will be.
100% of people have transponders above 3000 ft? This is not correct. Last weekend there were 2000 ish gliders flying, 99% with no transponder and most would have been at 3000+.
Some numbers;
There is about 7000 G reg c of a SEP aircraft. Most will have transponders, say 80%
There are 4000 micros, 99% will not have transponders. About 50% of these are “little aircraft” flown by ex C of A aircraft owners who fly them exactly the same as there old PA28/140’s (similar performance). Such people do not usually stooge around at low level.
There are 2200 LAA permit aircraft. Around 50% of these have radio, so less will have transponders. Reasonable guess, 30%? Most of these are flown by experienced PPL’s in the 50 + age bracket with old stile CAA PPL’s, who are as likely to fly at 3000 ft as anybody else.
Lastly, you have a very large number of paramotors, 12000+. These are mostly low level, but I have seen them at 4000ft, and they have flown over Everest.
The above represents the majority of UK light GA which will be flying on a Saturday afternoon in summer. The % with some kind of traffic avoidance system will be very low. There are only 2 – 400 PCAS units in the UK, Flarm is estimated at 200 and rising fast, TCAS etc is only on a small number of high end C of A machines. Last Saturday the few LARS units which were open were swamped and offering BS only, so right now we need to work on our lookout, encourage people to fit low cost traffic warning systems which are technically appropriate to the aircraft concerned and stop bleating for transponders.
Rod1
With all your experience you must have noticed that some VFR pilots are very good at spotting other traffic and some are not. The more one works on lookout and scan the better ones gets, but it is not 100% and never will be.
100% of people have transponders above 3000 ft? This is not correct. Last weekend there were 2000 ish gliders flying, 99% with no transponder and most would have been at 3000+.
Some numbers;
There is about 7000 G reg c of a SEP aircraft. Most will have transponders, say 80%
There are 4000 micros, 99% will not have transponders. About 50% of these are “little aircraft” flown by ex C of A aircraft owners who fly them exactly the same as there old PA28/140’s (similar performance). Such people do not usually stooge around at low level.
There are 2200 LAA permit aircraft. Around 50% of these have radio, so less will have transponders. Reasonable guess, 30%? Most of these are flown by experienced PPL’s in the 50 + age bracket with old stile CAA PPL’s, who are as likely to fly at 3000 ft as anybody else.
Lastly, you have a very large number of paramotors, 12000+. These are mostly low level, but I have seen them at 4000ft, and they have flown over Everest.
The above represents the majority of UK light GA which will be flying on a Saturday afternoon in summer. The % with some kind of traffic avoidance system will be very low. There are only 2 – 400 PCAS units in the UK, Flarm is estimated at 200 and rising fast, TCAS etc is only on a small number of high end C of A machines. Last Saturday the few LARS units which were open were swamped and offering BS only, so right now we need to work on our lookout, encourage people to fit low cost traffic warning systems which are technically appropriate to the aircraft concerned and stop bleating for transponders.
Rod1
Good on him, a good example of how to fly in a thoroughly professional manner
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Rod, it's indeed possible that your picture is closer to the mark for weekend traffic. I rarely fly at weekends.
My comment about the correlation between Mode C carriage and altitude is based on an obvious observation of traffic reports by radar ATC.
I tend to fly either just below CAS or (if CAS base is in IMC; often the case under the LTMA) just below the cloudbase, so there will be negligible GA traffic above me. The vast majority of traffic reported to me in this situation is "level unknown". Most of this traffic is never spotted (by me or passengers) but when it is spotted it turns out to be way down below.
If OTOH I fly higher up, 3000ft+ which a lot of the time is above cloud, the vast majority of traffic spotted is reported with a known level (Mode C).
Anyway I have written this before many times. Maybe everything changes when the weekend comes and suddenly all the non-transponding pilots climb to great heights?
Transponder use is (as you well know) not just for the benefit of the few TCAS-equipped Cirrus SR22s etc. You get
- protection to jet transport TCAS, should you bust CAS (of course you never bust CAS but hundreds of other pilots manage it every year, with plenty having near misses with 737s etc)
- protection to jet transport TCAS in Class G (the only solution to CAT in G is more CAS, which nobody in GA wants, do they??)
- radar ATC can see your level and pass it to other pilots (hardly any point in calling any ATC unit if they cannot provide a radar service, but a RS is near-useless without it seeing altitudes)
- easier to get CAS transits (apart from airspace rules, a transponder makes you appear more professional)
- visibility to other planes that carry TCAS (fixed or portable) systems
Considering the average 30 year old spamcan costs about £5000/year to drag through the Annual, I don't really see this argument anymore. And the vast majority of "homebuilt" planes can have one fitted too - even if battery powered.
My comment about the correlation between Mode C carriage and altitude is based on an obvious observation of traffic reports by radar ATC.
I tend to fly either just below CAS or (if CAS base is in IMC; often the case under the LTMA) just below the cloudbase, so there will be negligible GA traffic above me. The vast majority of traffic reported to me in this situation is "level unknown". Most of this traffic is never spotted (by me or passengers) but when it is spotted it turns out to be way down below.
If OTOH I fly higher up, 3000ft+ which a lot of the time is above cloud, the vast majority of traffic spotted is reported with a known level (Mode C).
Anyway I have written this before many times. Maybe everything changes when the weekend comes and suddenly all the non-transponding pilots climb to great heights?
Transponder use is (as you well know) not just for the benefit of the few TCAS-equipped Cirrus SR22s etc. You get
- protection to jet transport TCAS, should you bust CAS (of course you never bust CAS but hundreds of other pilots manage it every year, with plenty having near misses with 737s etc)
- protection to jet transport TCAS in Class G (the only solution to CAT in G is more CAS, which nobody in GA wants, do they??)
- radar ATC can see your level and pass it to other pilots (hardly any point in calling any ATC unit if they cannot provide a radar service, but a RS is near-useless without it seeing altitudes)
- easier to get CAS transits (apart from airspace rules, a transponder makes you appear more professional)
- visibility to other planes that carry TCAS (fixed or portable) systems
Considering the average 30 year old spamcan costs about £5000/year to drag through the Annual, I don't really see this argument anymore. And the vast majority of "homebuilt" planes can have one fitted too - even if battery powered.
Avoid imitations
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I can’t really believe ST does not understand, but I don’t know why he keeps hammering the point that SOME gliders have transponders, as if that means all could.
Please get down off your pedestal and read my post again. You are possibly now getting stuff I have posted mixed up with stuff posted by others! Of course I know that rules don't allow the fitting of certain equipment to certain aircraft. As I mentioned to you before, I too have no clearance to fit FLARM or anything other equipment to the public transport aircraft that I fly. It already has the mandatory CAA fit and more besides. It looks like there is no possibility of FLARM being given a certification for PT in the near future; each individual aircraft type and mark would need individual certification at huge cost; I've also mentioned that before. Not only that, the aircraft is not owned by me, I don't pay the bills and I have little say in these issues. It will eventually be decided by EASA / CAA legislation, probably when it becomes enough of an issue in the Sunday papers.
Those who say "well if you don't like it stay on the ground then" are avoiding the issue; if I stayed on the ground someone else would take my place. I have no intention of giving up flying for a living just yet; I've been doing it for 32 years and it's what I'm best qualified to do.
I began the post above that you seem to object to so strongly, by mentioning the fact that pilot was talking to an ATC unit on the radio. In the past you told me that gliders can't speak to ATC, either.
This pilot managed to make intelligent use of his on-board equipment and battery power, whether or not he had it switched on for the whole flight is irrelevant. I was impressed that he seemed so professional and I said so. What do you expect me to say? You don't like it whan folk criticise glider pilots and yet you complain even more strongly because I just praised one.
Perhaps he should have switched everything off, not spoken to ATC and I should have just looked out better? I suggest you give this a break, it seems to be getting to you; it's not your personal responsibility to answer everything posted here, with increasing angst. I'm going to comment no more, I've got some flights to plan.