Close Calls
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fireflybob
Absolutely, See and Avoid is an essential tool in the box, but it is not very good and needs all the assistance it can get!
I learned to fly in the civilian Gliding world which taught lookout very aggressively. I had always considered myself quite good at it until I got the PCAS box, which shattered the illusion quite quickly. I still work at see and avoid, but now I know how bad I am in comparison with the tec, and that only spots about 50% of the traffic within 5nm and 2000ft of me.
Pace, did you get a copy of the Flyer article on collision avoidance?
Rod1
Absolutely, See and Avoid is an essential tool in the box, but it is not very good and needs all the assistance it can get!
I learned to fly in the civilian Gliding world which taught lookout very aggressively. I had always considered myself quite good at it until I got the PCAS box, which shattered the illusion quite quickly. I still work at see and avoid, but now I know how bad I am in comparison with the tec, and that only spots about 50% of the traffic within 5nm and 2000ft of me.
Pace, did you get a copy of the Flyer article on collision avoidance?
Rod1
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Pace, did you get a copy of the Flyer article on collision avoidance?
Of course I did and it was an excellent well written piece. Thanks for all your efforts. Quite a celebrity
Pace
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Nobody would deny that the Mark I Eyeball has its limitations. Getting a little of the right kind of assistance is no bad thing.
HOWEVER, TCAS/PCAS/OCAS also have their limitations and cannot under any circumstances replace a bloody good lookout. They can't show anything not transponding, they can't show anything if the equipment fails, and as Pace so rightly says, they CAN very easily induce a false sense of security so that the lookout becomes lazier and less effective.
I train in an area that can on occasions become overrun with gliders, which very rarely carry transponders and often are non-radio as well. They don't reflect primary radar too well, so are all but invisible on radar, invisible on TCAS, and you need a damn good lookout to see such a slim fuselage and high aspect ratio wing.
So keep that lookout skill honed - or you will become (the cause of) another accident statistic sooner or later.
HOWEVER, TCAS/PCAS/OCAS also have their limitations and cannot under any circumstances replace a bloody good lookout. They can't show anything not transponding, they can't show anything if the equipment fails, and as Pace so rightly says, they CAN very easily induce a false sense of security so that the lookout becomes lazier and less effective.
I train in an area that can on occasions become overrun with gliders, which very rarely carry transponders and often are non-radio as well. They don't reflect primary radar too well, so are all but invisible on radar, invisible on TCAS, and you need a damn good lookout to see such a slim fuselage and high aspect ratio wing.
So keep that lookout skill honed - or you will become (the cause of) another accident statistic sooner or later.
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Although I have considered it I have not bought a PCAS unit - not all of us have unlimited flying budgets - I am with Captain Staple on this one. Flying VFR you should be able to see converging aircraft in time to take avoiding action. The exception is an aircraft converging directly ahead at 12 o'clock. I consider the chances of another aircraft being on a direct heading at exactly the same height very low indeed. Is there any recorded instance of this actually happening?
A few days ago I was on the downwind leg at Swansee when I saw an aircraft far ahead, seemingly outside the ATZ and heading off in a different direction. As I turned on to base leg it was suddenly in front of me and I turned to the right to move behind it.
Swansee is A/G radio but they obviously take their job seriously. I did hear them give airfield information to an aircraft AFTER I had begun my downwind leg and didn't hear any a/c call downwind or the A/G mention anything about other traffic in the circuit.
At this time A/G was strongly advising another a/c about to line up to hold as that pilot seemed not to be bothered looking for traffic on final.
Which makes me think the other airborne a/c was doing a straight-in approach or else a right hand circuit (A/G had notified a left hand circuit). It's pilot also seemed completely unaware of my presence behind and seemed to take forever to evacuate the runway!
So a lot of less than perfect airmanship - and I include myself in that!
By the way, is it acceptable to go and talk to staff in the tower after the event to get more information about what happened? I had no intention with fighting with anyone but it would be of interest.
A few days ago I was on the downwind leg at Swansee when I saw an aircraft far ahead, seemingly outside the ATZ and heading off in a different direction. As I turned on to base leg it was suddenly in front of me and I turned to the right to move behind it.
Swansee is A/G radio but they obviously take their job seriously. I did hear them give airfield information to an aircraft AFTER I had begun my downwind leg and didn't hear any a/c call downwind or the A/G mention anything about other traffic in the circuit.
At this time A/G was strongly advising another a/c about to line up to hold as that pilot seemed not to be bothered looking for traffic on final.
Which makes me think the other airborne a/c was doing a straight-in approach or else a right hand circuit (A/G had notified a left hand circuit). It's pilot also seemed completely unaware of my presence behind and seemed to take forever to evacuate the runway!
So a lot of less than perfect airmanship - and I include myself in that!
By the way, is it acceptable to go and talk to staff in the tower after the event to get more information about what happened? I had no intention with fighting with anyone but it would be of interest.
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By the way, is it acceptable to go and talk to staff in the tower after the event to get more information about what happened?
ATC units / AFISO units etc. all very much welcome pilots going to see what goes on, discussing any incidents whose dissection may lead to greater understanding of the other sides' problems and so on.
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The fact is that one CANNOT rely on the Mk1 eyeball. If you want to use stats to prove this, how many collisions have occured in VMC conditions? Pretty much ALL of them AFAIK.
TIS is a real benefit, and I fly aeroplanes with it around LA which is exceedingly busy as no doubt Socal will atest to, and I have had a number of close calls in the past over the famous Long Beach "practice area" - which has claimed numerous lives in recent history from midairs.
If anything TIS increases ones ability to visually acquire a target - rather than "keeping your head in the cockpit looking at a screen" as some people who probably have never used the system seem to imply. Also because you can see the altitude of conflicting traffic you know if there really is a risk or not. I had a controller clear an aircraft for a left hand departure from a right hand parallel runway just after I had taken off the left hand runway at night. The other aircraft passed overhead at less than 100' and it was only because TIS started screaming that we stopped our climb and put the nose down. being night it was very difficult to tell which way the aeroplane was actually moving until very close when things started to happen very quickly.
However, one thing that I have discovered is that luckily a midair is exceedingly unlikely. Even when your traffic system shouts "Traffic" at you most of the time there will be some offset in altitude - A miss is as good as a mile so even with 20' clearance, a collision won't occur. Still sods law and all that, and so if I see another target I have not visually acquired then I'll make sure there is some offset in altitude.
In the UK i have a Zaon XRX interfaced to my G496 which displays the traffic on it. It works well and certainly increases situational awareness.
TIS is a real benefit, and I fly aeroplanes with it around LA which is exceedingly busy as no doubt Socal will atest to, and I have had a number of close calls in the past over the famous Long Beach "practice area" - which has claimed numerous lives in recent history from midairs.
If anything TIS increases ones ability to visually acquire a target - rather than "keeping your head in the cockpit looking at a screen" as some people who probably have never used the system seem to imply. Also because you can see the altitude of conflicting traffic you know if there really is a risk or not. I had a controller clear an aircraft for a left hand departure from a right hand parallel runway just after I had taken off the left hand runway at night. The other aircraft passed overhead at less than 100' and it was only because TIS started screaming that we stopped our climb and put the nose down. being night it was very difficult to tell which way the aeroplane was actually moving until very close when things started to happen very quickly.
However, one thing that I have discovered is that luckily a midair is exceedingly unlikely. Even when your traffic system shouts "Traffic" at you most of the time there will be some offset in altitude - A miss is as good as a mile so even with 20' clearance, a collision won't occur. Still sods law and all that, and so if I see another target I have not visually acquired then I'll make sure there is some offset in altitude.
In the UK i have a Zaon XRX interfaced to my G496 which displays the traffic on it. It works well and certainly increases situational awareness.
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englishal, your post has a number of misconceptions and misunderstandings.
First:-
This is quite an extraordinary statement to make. It rather sets the tone for the rest of the post.
Secondly, you say
I am prepared to bet a considerable amount of money that I have used more TCAS systems than you. I have also written training modules for crews flying TCAS systems when they fiirst started becoming mandatory in larger aircraft. So let's not start slinging mud like that.
Third, nobody has said that we should "rely" on the Mark I eyeball solely. Situational awareness, ATC radar units and other systems (of which TCAS is just one) also have a major part to play.
Next, you state
That's fine if you rely 100% on what TCAS and your own altimetry is telling you. If you want to bet your life on that rather than having a look out of the window, then that's fine. Just don't go betting other people's lives on it as well. All it takes is a mis-set altimeter and bang - that's all she wrote.
Next, your near miss:-
Situational awareness should have alerted you to a very real and significant danger of collision. I suggest that you should have taken action well before the other aircraft got that close.
You say your wiggly amp devices are good for increasing situational awareness. I'm all for that. But anyone relying on such systems to give him first notice of traffic instead of starting off looking out of the window is an accident waiting to happen, and is a very silly pilot indeed.
Finally, a miss is very far from being as good as a mile. A little light aircraft thinking that 20' is fine and having a close encounter with something fast and heavy-ish doing close to 250 kts and pumping lots of hot air out the back is liable to be very upset. A physical collision is not necessary.
First:-
If you want to use stats to prove this, how many collisions have occured in VMC conditions? Pretty much ALL of them AFAIK.
Secondly, you say
some people who probably have never used the system
Third, nobody has said that we should "rely" on the Mark I eyeball solely. Situational awareness, ATC radar units and other systems (of which TCAS is just one) also have a major part to play.
Next, you state
Also because you can see the altitude of conflicting traffic you know if there really is a risk or not.
Next, your near miss:-
I had a controller clear an aircraft for a left hand departure from a right hand parallel runway just after I had taken off the left hand runway at night.
You say your wiggly amp devices are good for increasing situational awareness. I'm all for that. But anyone relying on such systems to give him first notice of traffic instead of starting off looking out of the window is an accident waiting to happen, and is a very silly pilot indeed.
Finally, a miss is very far from being as good as a mile. A little light aircraft thinking that 20' is fine and having a close encounter with something fast and heavy-ish doing close to 250 kts and pumping lots of hot air out the back is liable to be very upset. A physical collision is not necessary.
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This is quite an extraordinary statement to make. It rather sets the tone for the rest of the post.
If you want to bet your life on that rather than having a look out of the window, then that's fine.
and so if I see another target I have not visually acquired then I'll make sure there is some offset in altitude.
That's fine if you rely 100% on what TCAS and your own altimetry is telling you. If you want to bet your life on that rather than having a look out of the window, then that's fine. Just don't go betting other people's lives on it as well. All it takes is a mis-set altimeter and bang - that's all she wrote.
Situational awareness should have alerted you to a very real and significant danger of collision. I suggest that you should have taken action well before the other aircraft got that close.
I'm sure you are a TCAS SkyGod but please tell me out of all the collisions in recent history how many have happened in VMC conditions (and hence see and avoid apply, even under IFR) and how many in IMC (where see and avoid is not applicable). I can't think of one having happened in IMC which leads me to the conclusion that the "Mk 1 eyeball" has its failings as well as any other system. Combine them both and you have the best of both worlds, though your first post seemed to indicate that you were an "anti-technologist" who thinks that all things TCAS and GPS are evil....
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Blimey, where does one start?
You say, without evidence of blushing or presentation of reference or reputable authority, "If you want to use stats to prove this, how many collisions have occured in VMC conditions? Pretty much ALL of them AFAIK."
When I query this, you then say "Why is it? It is fact. Even under IFR "see and avoid" still applies."
Wrt the Hawker/Glider accident, you say "They were both responsible for See and Avoid being in VMC." And they failed to do so, didn't they? Perhaps the 800 pilot decided simply "In TCAS we trust".
You wanted to bring up statistics - you quote them. Don't present something you've made up and then challenge me to prove the opposite.
I note in your further elaboration of your near miss that at no time did you make a call to alert either the Tower or the other aircraft to your presence. You decided it was "safe to assume" he knew. It's never safe to assume anything. In fact, it's bloody stupid to make assumptions where safety is concerned.
And when you knew an aircraft was being launched on a collision course with you, and you knew where he was relative to you, you decided to get your head inside rather than keeping all your attention on where he actually was? The mind boggles.
I make no claim to be any kind of a God. I do, however, know the rules about collision avoidance, how to use TCAS, and what one does in IFR compared to VFR.
For example, if you are under positive radar control while still in VMC, I am not going to blindly plough into another aircraft simply because ATC told me to fly this heading. Nor am I going to ignor a collision avoidance call from my TCAS. I shall pull up (if that's the action advised) and tell ATC "TCAS Climb". Similarly, in IMC the rule is NOT "see and avoid" as you seem to think. Looking out can still help, however.
You say, without evidence of blushing or presentation of reference or reputable authority, "If you want to use stats to prove this, how many collisions have occured in VMC conditions? Pretty much ALL of them AFAIK."
When I query this, you then say "Why is it? It is fact. Even under IFR "see and avoid" still applies."
Wrt the Hawker/Glider accident, you say "They were both responsible for See and Avoid being in VMC." And they failed to do so, didn't they? Perhaps the 800 pilot decided simply "In TCAS we trust".
You wanted to bring up statistics - you quote them. Don't present something you've made up and then challenge me to prove the opposite.
I note in your further elaboration of your near miss that at no time did you make a call to alert either the Tower or the other aircraft to your presence. You decided it was "safe to assume" he knew. It's never safe to assume anything. In fact, it's bloody stupid to make assumptions where safety is concerned.
And when you knew an aircraft was being launched on a collision course with you, and you knew where he was relative to you, you decided to get your head inside rather than keeping all your attention on where he actually was? The mind boggles.
I make no claim to be any kind of a God. I do, however, know the rules about collision avoidance, how to use TCAS, and what one does in IFR compared to VFR.
For example, if you are under positive radar control while still in VMC, I am not going to blindly plough into another aircraft simply because ATC told me to fly this heading. Nor am I going to ignor a collision avoidance call from my TCAS. I shall pull up (if that's the action advised) and tell ATC "TCAS Climb". Similarly, in IMC the rule is NOT "see and avoid" as you seem to think. Looking out can still help, however.
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Thanks for that, SoCal.
I'm not sure how the USA statistics compare to UK statistics, but probably about equivalent. Given the fact that one is in VMC a lot more than IMC, I'm not very surprised that's how they pan out. Very far from "almost all".
Incidentally, the UK Airprox Board state:-
From Lessons Identified | UK Airprox Board
I'm not sure how the USA statistics compare to UK statistics, but probably about equivalent. Given the fact that one is in VMC a lot more than IMC, I'm not very surprised that's how they pan out. Very far from "almost all".
Incidentally, the UK Airprox Board state:-
About 10% of all Airprox are glider-related – that’s about 20 incidents a year. Almost all occur in Class G airspace which is of course for everyone to use. In such airspace, “see and avoid” is the primary means of collision avoidance.
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heh heh...whatever 
I suppose at 350 kts things happen even quicker. It is hard enough to see a glider at 100kts, let alone at 350+ (this was at 16000' too) so perhaps they just didn't see each other??!?
Go through all the AAIB reports and NTSB reports and read them for yourself. I have read a good many of them and don't recall one being in IMC. I can't be bothered to spoon feed them to you.
Perhaps you should ask yourself why more and more glider pilots are taking up FLARM, and why many in Europe already use FLARM. Perhaps nothing better than see and avoid has existed for GA aircraft until now?
And they failed to do so, didn't they? Perhaps the 800 pilot decided simply "In TCAS we trust".
You wanted to bring up statistics - you quote them. Don't present something you've made up and then challenge me to prove the opposite.
About 10% of all Airprox are glider-related – that’s about 20 incidents a year. Almost all occur in Class G airspace which is of course for everyone to use. In such airspace, “see and avoid” is the primary means of collision avoidance.
From Lessons Identified | UK Airprox Board
From Lessons Identified | UK Airprox Board
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To inject some facts;
On average 3 – 4 people a year die in mid air collisions in UK GA (that includes self launching motor gliders but not other forms of glider) (AAIB umbers)
Mid air collisions are one of the big three killers in gliding, and the BGA has recently issued a statement supporting collision avoidance devices being used to assist lookout.
If you read the accident reports, like the 2007 incident in the midlands, you will see that unless you have x-ray vision to see through the aircraft structure, you cannot see all the threats. In the 2007 incident the Luscome turned to avoid a micro and was “collected” by a turboprop doing 160kn. The Luscome pilot could not have seen the turboprop. Of the three aircraft only the TP had a transponder, but if the Luscome had had PCAS he would have at least had a chance.
In the UK about 50% of GA has a transponder. 15% of gliders have FLARM, but this is rising rapidly as it only became legal to use it in October last year.
Devices that detect both Mode C, Mode S, ADS-B and FLARM are going to be available early next year.
If you do a search on see and avoid you will find several studies. All are very negative about its effectiveness. I think we all need to work on our lookout, but we also need to consider if some tec can help us.
Rod1
On average 3 – 4 people a year die in mid air collisions in UK GA (that includes self launching motor gliders but not other forms of glider) (AAIB umbers)
Mid air collisions are one of the big three killers in gliding, and the BGA has recently issued a statement supporting collision avoidance devices being used to assist lookout.
If you read the accident reports, like the 2007 incident in the midlands, you will see that unless you have x-ray vision to see through the aircraft structure, you cannot see all the threats. In the 2007 incident the Luscome turned to avoid a micro and was “collected” by a turboprop doing 160kn. The Luscome pilot could not have seen the turboprop. Of the three aircraft only the TP had a transponder, but if the Luscome had had PCAS he would have at least had a chance.
In the UK about 50% of GA has a transponder. 15% of gliders have FLARM, but this is rising rapidly as it only became legal to use it in October last year.
Devices that detect both Mode C, Mode S, ADS-B and FLARM are going to be available early next year.
If you do a search on see and avoid you will find several studies. All are very negative about its effectiveness. I think we all need to work on our lookout, but we also need to consider if some tec can help us.
Rod1
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The newer devices certainly offer TIS like performance and FLARM, the latest one I have seen is LX avionics Ltd - Traffic Monitor which with the capability of adding mode C looks a very capable unit.
I'd love to think that I can spot all the other traffic - but I know I cann't. In this neck of the woods high speed military traffic can be found pretty much anywhere in the usual VFR range of heights. Spotting a single aircraft is really bad news as they generally operate in pairs - so any odd number suggested you have either missed the leader or the wingman - which? you'll never know......
Gadgets like this would really help.
I'd love to think that I can spot all the other traffic - but I know I cann't. In this neck of the woods high speed military traffic can be found pretty much anywhere in the usual VFR range of heights. Spotting a single aircraft is really bad news as they generally operate in pairs - so any odd number suggested you have either missed the leader or the wingman - which? you'll never know......
Gadgets like this would really help.
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A couple of years ago I flew as passenger seated behind the pilot in a Chipmunk going to a display as one of the Red Sparrows Team
The pilot was a serving senior ranking RAF officer,ex fighter pilot.
I was amazed at the thoroughness of his lookout.
He never stopped scanning the sky, up and down and from one side to the other all the time we were airborne.
I always try to emulate him when I fly.
Lister
The pilot was a serving senior ranking RAF officer,ex fighter pilot.
I was amazed at the thoroughness of his lookout.
He never stopped scanning the sky, up and down and from one side to the other all the time we were airborne.
I always try to emulate him when I fly.
Lister
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Very rarely, gasax - they don't usually have TXPDR on.
I believe that although maybe only 50% of GA have txpdrs, those who are either based at, based near to "big" airfields and CAS normally do, and that those who tend to do cross country trips probably will have and use a transponder.
I try and go high - go at 7000 + if you can,lookout and use any available technology to help.
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Flying high is a good tactic, but it is only of limited use.
You have to get up there and the first 3000 feet are the risky bit.
You have to come down and that is usually in a busy bit of airspace
You cannot normally fly high in the UK, as Class A forces you down.
I suspect we will see an increase in collisions as controlled airspace expands.
Rod1
You have to get up there and the first 3000 feet are the risky bit.
You have to come down and that is usually in a busy bit of airspace
You cannot normally fly high in the UK, as Class A forces you down.
I suspect we will see an increase in collisions as controlled airspace expands.
Rod1
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You'll generally find that Mill traffic squawks on departure from their base, when in the vicinity of known other traffic. Thereafter, FJ traffic will turn it off when on exercise. Therefore they're unlikely to be squawking when blatting around the "wide open spaces" at MachLots and FL 0.5. Such, at least, is my understanding from participating in ShareSpace a few years ago.