Improve Light A/C Separation
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Rod1. Your para 5; agree entirely.
Not GPS but the number of times I've flown abeam the LIC NDB and watched GA traffic pass its overhead at similar levels but seemingly oblivious to each other's presence is quite alarming.
For the record, I do not want any transponder in my aeroplane (I've better things to route the limited juice through and squander lift on); ENDEX. I have windows and perfectly good (and trained, disciplined) MK 1 eyeballs.
Not GPS but the number of times I've flown abeam the LIC NDB and watched GA traffic pass its overhead at similar levels but seemingly oblivious to each other's presence is quite alarming.
For the record, I do not want any transponder in my aeroplane (I've better things to route the limited juice through and squander lift on); ENDEX. I have windows and perfectly good (and trained, disciplined) MK 1 eyeballs.
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My (limited) experience of TCAS in a 182T (G1000) is that it's useful on route but it's value diminishes as one closes on a GA airport with a busy circuit. Any circuit traffic sends it nuts and the continual TRAFFIC warnings just become a distraction. I guess it's possible we don't have it set up right.
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Just to clarify terminology.. . . .
When we refer to "TCAS" it is only applicable to "TCAS II" equipped flying machines.
When we refer to "TCAS" it is only applicable to "TCAS II" equipped flying machines.
Other systems in use such as TPAS, FLARM, etc, are not TCAS systems.
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Rod1 & GBZ...."Not GPS but the number of times I've flown abeam the LIC NDB and watched GA traffic pass its overhead at similar levels but seemingly oblivious to each other's presence is quite alarming"
I'm quite astonished to see the amount of traffic that uses airfields as navigational waypoints by flying directly over them at 2050' (estimated!). Common sense suggests to me that flying directly over NDB's/VOR's/VRP's and airfields is best avoided, particularly at around 2000'. Why don't pilots navigate with some sort of offset from the feature that they're using ? Actually, thinking about it, the more pilots who navigate this way, the safer it is for me as I avoid such hotspots!
I'm quite astonished to see the amount of traffic that uses airfields as navigational waypoints by flying directly over them at 2050' (estimated!). Common sense suggests to me that flying directly over NDB's/VOR's/VRP's and airfields is best avoided, particularly at around 2000'. Why don't pilots navigate with some sort of offset from the feature that they're using ? Actually, thinking about it, the more pilots who navigate this way, the safer it is for me as I avoid such hotspots!
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Maybe it should be a choice to have TCAS but compulsory to have at least mode C transponder for all flying machines?
The problem you "fight" is that you, with a TCAS / PCAS / Skywatch / FLARM or whatever are expecting / relying on someone else to purchase / fit / get approved a device to make yours work. Some of the latter would, maybe quite rightly, ask you to pay for it? *
I do not know the numbers who have Mode C / Mode S / FLARM / whatever, but for collision avoidance purposes, especially given the lack of radar service(s), we are surely a long way from the "critical mass" to significantly reduce the chance of a mid-air?
NoD
PS before it gets personal, we are just fitting Mode S, but for other reasons...
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If on a visual approach, the rule is "see and be seen" 100% lookout and no gadgets to help. I appreciate this as a former fast jet and airline pilot; I also used to be a CVT resident before moving to Scotland, Now a pensioner, too!!
dbee
dbee
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I'm quite astonished to see the amount of traffic that uses airfields as navigational waypoints by flying directly over them at 2050' (estimated!). Common sense suggests to me that flying directly over NDB's/VOR's/VRP's and airfields is best avoided, particularly at around 2000'. Why don't pilots navigate with some sort of offset from the feature that they're using ? Actually, thinking about it, the more pilots who navigate this way, the safer it is for me as I avoid such hotspots!
Navaids and airfields are all in the GPS database under their normal ICAO code so it's easy to string a bunch of them together to make a route, then follow the magenta line.
(VRPs are a different matter. Most GPS databases have a limit to the length of a waypoint and a VRP like "South Woodham Ferrers" has to be abbreviated, which doesn't happen in a consistent way across GPSs and GPS manufacturers, or omitted altogether.)
But even without GPS, navaids are intended as navaids: string them together to form a route, then fly the route with fairly simple nav equipment. And airfields are rather easy to recognize and identify from the air if your nav is purely visual/DR.
But I agree that it concentrates the traffic, particularly in busy areas or areas without much else to base your navigation on, onto a single point in space. Flying offset (in case of a GPS not that hard to do, just make sure the cross track error is constant at 1 nm or so) would make a lot of sense.
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I do not know the numbers who have Mode C / Mode S / FLARM / whatever, but for collision avoidance purposes, especially given the lack of radar service(s), we are surely a long way from the "critical mass" to significantly reduce the chance of a mid-air?
From my 900hrs of flying, with as much under an RIS as I can get, of the "level unknown" i.e. nontransponding contacts that I recall spotting, countless contacts were below me, and none that I ever recall was above me. (Of course the majority I never spotted). The statistical picture here is overwhelming and that is why I sometimes appear a bit cynical on this forum about the correlation between who is flying without a transponder (often a homebuilt/microlight type) and how low they fly, and probably how far (I mean not far) they fly.
Practically everybody who flies seriously, doing real distances and using the available airspace to the full, has a Mode C at least and uses it. But there is a large and vocal group who are against transponders but who probably do little beyond local bimbles, at low levels.
(time to duck under the barrage of examples of adventurers who flew their motorised hang glider all the way to Kathmandu, etc)
Backpacker - I don't think airfields generally make good waypoints. I would challenge you to to a dead reckoning exercise with say 10 waypoints, all of them being grass-only ones. Some are damn hard to spot for a visitor (easy for locals, obviously). And the bigger ones have an ATZ so you have to be at least 2000ft AGL and preferably more due to overhead joins at 2000ft, and you ought to talk to them. I never use airfields as waypoints, in the GPS route. They have minimal visual benefit - unless it's Heathrow
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IO540
“That depends on where you fly. If you fly at 1000ft then I agree 100%. If you fly at 3000ft+ then I am sure nearly all are Mode C/S equipped and transponding.
From my 900hrs of flying,”
The trouble is I have more than 900 hours, I actually fly one of these and I KNOW they fly 2-5000 ft on a regular basis!
“and how low they fly, and probably how far”
A typical 912 powered machine will climb at over 1000 fpm (mine is typically around 1700 fpm) and cruse at 100kn+ (mine does 138kn at 75%). Why would such aircraft a) fly low or B) stay at home. I am based on a strip with 18 other aircraft 2 of which have C of A and most fly significant distances and at normal GA levels using normal GA methods. The majority are flown by ex spamcan drivers who have found a “better” way. If you were to argue that weight shift micros were flown low you would have more of a point (about 3000 aircraft not transponder equipped), but now the engines are getting bigger you increasingly see them at 2-3000 ft too.
The LAA hold a series or regional rallys around the country. You will find 200 + aircraft a day visiting from all over the UK, with some from Europe. The picture of a home built / micro which is just capable of getting airborne is completely out of date. A CT Micro (factory built) will do 120kn with 4 hours fuel, nobody flyes such a machine at low level, too many ATZ, MATZ etc. The 12000 paramoters probably do fly low, but add in the gliders and traditional transponder equipped GA is a minority at 3000 ft on a summer’s weekend
I raise the above so that we all understand the problem. The CAA came in all guns blazing for every flying machine to be fitted with mandatory Mode S. Just a few short month ago they accepted it was an impossible dream for a host of reasons. Current technology transponders will never be made mandatory for all airspace users. If we are serious about improving separation we must go back to basics and be prepared to retrain people in better lookout and test to measure the improvement. This is the only game in town right now. If there is a form of airborne radar we can fit which detects non transponding aircraft, costs 2k and 2kg then I will buy one now, but until then go out and get your eyes tested and clean the canopy.
Rod1
“That depends on where you fly. If you fly at 1000ft then I agree 100%. If you fly at 3000ft+ then I am sure nearly all are Mode C/S equipped and transponding.
From my 900hrs of flying,”
The trouble is I have more than 900 hours, I actually fly one of these and I KNOW they fly 2-5000 ft on a regular basis!
“and how low they fly, and probably how far”
A typical 912 powered machine will climb at over 1000 fpm (mine is typically around 1700 fpm) and cruse at 100kn+ (mine does 138kn at 75%). Why would such aircraft a) fly low or B) stay at home. I am based on a strip with 18 other aircraft 2 of which have C of A and most fly significant distances and at normal GA levels using normal GA methods. The majority are flown by ex spamcan drivers who have found a “better” way. If you were to argue that weight shift micros were flown low you would have more of a point (about 3000 aircraft not transponder equipped), but now the engines are getting bigger you increasingly see them at 2-3000 ft too.
The LAA hold a series or regional rallys around the country. You will find 200 + aircraft a day visiting from all over the UK, with some from Europe. The picture of a home built / micro which is just capable of getting airborne is completely out of date. A CT Micro (factory built) will do 120kn with 4 hours fuel, nobody flyes such a machine at low level, too many ATZ, MATZ etc. The 12000 paramoters probably do fly low, but add in the gliders and traditional transponder equipped GA is a minority at 3000 ft on a summer’s weekend
I raise the above so that we all understand the problem. The CAA came in all guns blazing for every flying machine to be fitted with mandatory Mode S. Just a few short month ago they accepted it was an impossible dream for a host of reasons. Current technology transponders will never be made mandatory for all airspace users. If we are serious about improving separation we must go back to basics and be prepared to retrain people in better lookout and test to measure the improvement. This is the only game in town right now. If there is a form of airborne radar we can fit which detects non transponding aircraft, costs 2k and 2kg then I will buy one now, but until then go out and get your eyes tested and clean the canopy.
Rod1
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"If you fly at 3000ft+ then I am sure nearly all are Mode C/S equipped and transponding"
As a converse example, on Saturday 23rd August there were (NOTAM'd) gliding competitions at Dunstable, Lasham, Bicester, Pocklington, Husbands Bosworth and Aston Down. These alone will have accounted for around 200 gliders airborne between 12:00-16:00. Cloudbase in the task area (basically most of Southern England) was between 3000-6000'. Therefore I'm pretty sure there'll have been several hundred non-transponder equipped aircraft operating between 1000'-10,000'. Anybody out flying that might day might ponder on how many gliders they saw (and importantly, how many they didn't).
As a converse example, on Saturday 23rd August there were (NOTAM'd) gliding competitions at Dunstable, Lasham, Bicester, Pocklington, Husbands Bosworth and Aston Down. These alone will have accounted for around 200 gliders airborne between 12:00-16:00. Cloudbase in the task area (basically most of Southern England) was between 3000-6000'. Therefore I'm pretty sure there'll have been several hundred non-transponder equipped aircraft operating between 1000'-10,000'. Anybody out flying that might day might ponder on how many gliders they saw (and importantly, how many they didn't).
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The CAA came in all guns blazing for every flying machine to be fitted with mandatory Mode S. Just a few short month ago they accepted it was an impossible dream for a host of reasons.
About 30 yrs ago students at Cranfield uni experimented with a system that detected aircraft strobe lights. It was basically sphere covered with photelectic cells that detected the flash from the strobe lights.
This info was then displayed on the flight deck.
With the vast development in electronics since the would this be a possibility?
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Outside of gliding competitions, there were also plenty of people flying above 3000 feet on other tasks, whether self-selected or club gliding tasks. I flew from Essex to Saltby, Lincolnshire, and back to Ely, much of the time above 3000 feet. I encountered several other gliders at similar heights, nothing to do with the main competitions.
The previous week, when flying between Cambridge and Suffolk in the Lakenheath area, I heard the pilot of a transponder-equipped aircraft near Bury St Edmunds making repeated efforts for his squawk to be seen, and Lakenheath could see nothing of him, on either primary or secondary radar. So please don’t think that having a transponder automatically makes you visible to air traffic control. Like any other machine, they are not 100% reliable.
Regarding wider use of FLARM, my personal opinion is that for the UK, use by gliders will increase slowly from a few per cent to a significant proportion, when the critical mass will be perceived as being large enough to encourage most glider pilots to use it. Unless something better comes along for powered GA, I think it quite possible that the same thing would happen, with the timing a few years later. [Always provided that it is permitted, and not prohibited, by the CAA or other authorities.] I suspect that the middle phase, rapid increase in use once a critical mass is reached, will happen because those without will be shown how many more aircraft they can’t see that are in fact detectable. Just my opinion.
Chris N.
The previous week, when flying between Cambridge and Suffolk in the Lakenheath area, I heard the pilot of a transponder-equipped aircraft near Bury St Edmunds making repeated efforts for his squawk to be seen, and Lakenheath could see nothing of him, on either primary or secondary radar. So please don’t think that having a transponder automatically makes you visible to air traffic control. Like any other machine, they are not 100% reliable.
Regarding wider use of FLARM, my personal opinion is that for the UK, use by gliders will increase slowly from a few per cent to a significant proportion, when the critical mass will be perceived as being large enough to encourage most glider pilots to use it. Unless something better comes along for powered GA, I think it quite possible that the same thing would happen, with the timing a few years later. [Always provided that it is permitted, and not prohibited, by the CAA or other authorities.] I suspect that the middle phase, rapid increase in use once a critical mass is reached, will happen because those without will be shown how many more aircraft they can’t see that are in fact detectable. Just my opinion.
Chris N.
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IO and Rod
I think there are a few issues at work.
I commented earlier on a recent trip to the West Country.
In both directions it would have been difficult or impossible to fly at altitude without an instrument rating. This summer such conditions have been a common feature of the weather. To remain "VFR" (and even then not strickly legal) you might have weaved around the cloud or found a route on top but even then without an instrument rating a route down was far from assured.
I think this means that had the viz been 10K with a base well above GA levels there might have been more of a mix of traffic but the fact of the matter is there wasnt and that seems to be typical of any number of trips this year.
For that reason I think LAA types will often be "held down" by the weather but when the weather is good we will increasingly see their numbers grow at higher levels.
In my view there is no doubt the percentage of faster traffic has grown. As you say LAA types are flying at speeds that were never obtainable not that many years ago and there are more fast singles around.
To nail my colours to the mast I dont believe see and avoid works - or should I have said works sufficiently well enough of the time. The faster the traffic the more this becomes true.
It leaves me wondering if we are not going to mandate the carriage of transponders for all traffic we should mandate its carriage for traffic flying above a certain speed or above a certain altitude (regardless of the class of airspace). At least that would mean in the second instance we could be assured that en route above a certain altitude we were no longer totally reliant on see and avoid.
I remember many years ago coming across a hang glider at just over 5,000 feet. Given that the terrain was at most 700 feet I never expected to see him there (all his mates were at least 2,000 feet below). He was legal and he was entitled to be there. Perhaps I should even have expected to come across him. However, despite his slow speed he presented a very poor target - I hasten to add we never the less managed to avoid each other!
I appreciate this may not suite the gliding community or some paraponting and hang gliding sites but how much of this traffic is en route? NOTAMing or establish "danger areas" around sites with non transponding traffic operating above the transponder base might help accomodate all.
I think there are a few issues at work.
I commented earlier on a recent trip to the West Country.
In both directions it would have been difficult or impossible to fly at altitude without an instrument rating. This summer such conditions have been a common feature of the weather. To remain "VFR" (and even then not strickly legal) you might have weaved around the cloud or found a route on top but even then without an instrument rating a route down was far from assured.
I think this means that had the viz been 10K with a base well above GA levels there might have been more of a mix of traffic but the fact of the matter is there wasnt and that seems to be typical of any number of trips this year.
For that reason I think LAA types will often be "held down" by the weather but when the weather is good we will increasingly see their numbers grow at higher levels.
In my view there is no doubt the percentage of faster traffic has grown. As you say LAA types are flying at speeds that were never obtainable not that many years ago and there are more fast singles around.
To nail my colours to the mast I dont believe see and avoid works - or should I have said works sufficiently well enough of the time. The faster the traffic the more this becomes true.
It leaves me wondering if we are not going to mandate the carriage of transponders for all traffic we should mandate its carriage for traffic flying above a certain speed or above a certain altitude (regardless of the class of airspace). At least that would mean in the second instance we could be assured that en route above a certain altitude we were no longer totally reliant on see and avoid.
I remember many years ago coming across a hang glider at just over 5,000 feet. Given that the terrain was at most 700 feet I never expected to see him there (all his mates were at least 2,000 feet below). He was legal and he was entitled to be there. Perhaps I should even have expected to come across him. However, despite his slow speed he presented a very poor target - I hasten to add we never the less managed to avoid each other!
I appreciate this may not suite the gliding community or some paraponting and hang gliding sites but how much of this traffic is en route? NOTAMing or establish "danger areas" around sites with non transponding traffic operating above the transponder base might help accomodate all.
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It leaves me wondering if we are not going to mandate the carriage of transponders for all traffic we should mandate its carriage for traffic flying above a certain speed or above a certain altitude (regardless of the class of airspace).
Conspicuity Code
When operating at and above FL 100 pilots shall select code 7000 and Mode C except:
(a) when receiving a service from an ATS Unit or Air Defence Unit which requires a different setting;
(b) when circumstances require the use of one of the Special Purpose Codes or one of the other specific conspicuity codes assigned
in accordance with the UK SSR Code Assignment Plan as detailed in the table at ENR 1-6-2-5 to ENR 1-6-2-10.
When operating at and above FL 100 pilots shall select code 7000 and Mode C except:
(a) when receiving a service from an ATS Unit or Air Defence Unit which requires a different setting;
(b) when circumstances require the use of one of the Special Purpose Codes or one of the other specific conspicuity codes assigned
in accordance with the UK SSR Code Assignment Plan as detailed in the table at ENR 1-6-2-5 to ENR 1-6-2-10.
NoD
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I suspect you mean though wanting a much lower altitude
confining the nasty LAA types to <2000' where they can have even more chance of bumping into each other
Confining non transponding aircraft of any type.
I wonder what percentage of LAA types are unable to fit a transponder (because of weight or power) and what percentage are unwilling because of cost?
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I wonder what percentage of LAA types are unable to fit a transponder (because of weight or power) and what percentage are unwilling because of cost?
I am not sure it would achieve much, since mid-airs seem to happen in the lower levels (?), and you would still have to transit in and out of the "upper areas" through the "danger zone" (unless you could confine that to CAS).
The 10,000' is a long established rule? What would you change it to? On what basis/reasoning? What arguments would alter the debate we have just been through? Would it be amsl? Or agl?
NoD
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I started this thread to try and prevent another terrible accident.
It seems to be going the way of most threads and ignoring the core question.
How can we stop banging into each other?
We all have to share the same airspace irrespective of the type of flying we do.
Please lets try to have constructive discussion.
It seems to be going the way of most threads and ignoring the core question.
How can we stop banging into each other?
We all have to share the same airspace irrespective of the type of flying we do.
Please lets try to have constructive discussion.
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NoD
For the purpose of debate (because I am not certain my proposal is serious)
1. I agree most collisions occur in or around the circuit. However, see and avoid should work well in the circuit (the fact it doesnt may be for other reasons). Nearly all the traffic (around GA airports at any rate) is likely to be slow moving. The circuit should help pilot's know where to look for traffic. Where there is AT they should provide additional help.
2. The 10,000 foot rule is well established but how much GA traffic is there above 10,000 feet? Very little. Oxygen constraints provide little headroom above 10,000 feet for most, combined with semi-circular or quadrangle levels and CAS. In short I would suggest the 10,000 rule is largely irrelevant to GA.
3. Providing a corridor above the terrain but below transponding height would point in favour of agl however I am not in favour of the use of dual or alternate altimeter settings.
4. Perhaps 10,000 feet is simply too high to be relevant but that opens up the debate as to what would be a more sensible height / level.
5. As I commented earlier perhaps speed would provide a better common demoninator. How many aircraft capable of flying above 100 knots indicated are incapable of fitting a transponder for reasons other than cost or desire?
Robin 400
I dont see your point.
I agree there are many aspects to avoiding collisions. Only one aspect is the impact of PCAS, TAS and TCAS but I think it is very relevant. A PCAS unit can now be purchased for a few hundred pounds and fitted to anything that is capable of getting airborne! I have noticed the up take of these units has significantly increased but of course there is no relevant training involved in their use and their limitations.
By all means lets discuss how we can adapt our flying to reduce the risk of collision a very effective means of reducing the risk - the floor is yours on that topic as you wish. I will be happy to chip in.
For the purpose of debate (because I am not certain my proposal is serious)
1. I agree most collisions occur in or around the circuit. However, see and avoid should work well in the circuit (the fact it doesnt may be for other reasons). Nearly all the traffic (around GA airports at any rate) is likely to be slow moving. The circuit should help pilot's know where to look for traffic. Where there is AT they should provide additional help.
2. The 10,000 foot rule is well established but how much GA traffic is there above 10,000 feet? Very little. Oxygen constraints provide little headroom above 10,000 feet for most, combined with semi-circular or quadrangle levels and CAS. In short I would suggest the 10,000 rule is largely irrelevant to GA.
3. Providing a corridor above the terrain but below transponding height would point in favour of agl however I am not in favour of the use of dual or alternate altimeter settings.
4. Perhaps 10,000 feet is simply too high to be relevant but that opens up the debate as to what would be a more sensible height / level.
5. As I commented earlier perhaps speed would provide a better common demoninator. How many aircraft capable of flying above 100 knots indicated are incapable of fitting a transponder for reasons other than cost or desire?
Robin 400
I dont see your point.
I agree there are many aspects to avoiding collisions. Only one aspect is the impact of PCAS, TAS and TCAS but I think it is very relevant. A PCAS unit can now be purchased for a few hundred pounds and fitted to anything that is capable of getting airborne! I have noticed the up take of these units has significantly increased but of course there is no relevant training involved in their use and their limitations.
By all means lets discuss how we can adapt our flying to reduce the risk of collision a very effective means of reducing the risk - the floor is yours on that topic as you wish. I will be happy to chip in.