OpenFLARM project

[bcw]

Originally Posted by crablab

The other *massive* advantage of PilotAware that has not been mentioned as far as I can see, is that with a Mode S transponder it can be configured to make ADS-B broadcasts - along the open standard, that all the controllers and commercial traffic use. Surely this is better than FLARM etc? It is certainly cheaper than the £2.5k needed for the "official" unit and before people ask, yes it is allowed and has been "approved" by the CAA.

That would be a massive advantage, but as far as I am aware it is not the case. Yes it can do it technically, but the regulations state that an approved and certified GPS source must be used. Pilot Aware is neither and therefore you would be breaking the law if you connected it to your transponder.

This was also mentioned above by PaulisHome:

Originally Posted by PaulisHome

Regulation is probably actually getting in the way. In the UK there are some trials of ADSB with low cost GPSs, but they are moving awfully slowly.

[crablab]

Originally Posted by bcw

That would be a massive advantage, but as far as I am aware it is not the case. Yes it can do it technically, but the regulations state that an approved and certified GPS source must be used. Pilot Aware is neither and therefore you would be breaking the law if you connected it to your transponder.

Did you read my last sentence?
You can do it, legally, with PilotAware, without a certified GPS.

Read here

[FullWings]

It’s great that people are developing cheaper and (hopefully) less proprietary electronic conspicuity systems but interoperability appears to be slipping down the priority list.

Barely a week or two goes by in UK airspace where there isn’t some form of near get-together that could have been prevented by devices (and people) talking to each other. VHF/UHF, XPDR, FLARM, PilotAware, ADSB, SSR... The information needed to prevent collisions is mostly out there and has been for some time but the multiplicity of formats seems to be preventing an effective one-stop solution.

I am much reminded of:

[crablab]

FullWings: entirely agree. But ADS-B IS the standard, isn't it? the FAA mandate it and it's being pushed by EASA. FLARM, OpenFLARM, P3i etc. have just sprung up of their own accord as a "distraction" from the main problem: ADS-B has been too expensive in the past to install. Now, it's getting slightly cheaper to have certified GPS etc. but the cheapest option still seems to be uncertified GPS with PAW, giving you both ADS-B in and out. The equivalent panel transponder from Garmin that does that is about £5k.

[FullWings]

True. I don’t understand enough about the technicalities of ADS-B to know if you could get FLARM-equivalent performance from ADS-B data. If that works, then great.

For instance, this year there will be 100+ gliders and light aircraft in the immediate vicinity of Lasham before the tasks start at the European Championships this August. If they were all squawking, it would be a mess but FLARM seems to be able to cope as they all carry it.

[ChickenHouse]

ADS-B In/Out could serve perfectly, if not better, than Flarm, BUT physics comes right at the corner. The US already had to introduce UAT to free available bandwidth from 1090ES and if we really would all go for an ADS-B 1090ES solution, the gibberish of all that stations will congest the air. Flarm did overcome some of the restrictions by reducing power, so making the area covered "fit for purpose of the gliders". Now with the new PowerFlarm the advantage gets less ... Same trouble as with radios, as long as we all had 3 to 5 Watts of power, we could reach the next airport and traffic control, now we blow our stumbling with 16 Watts from final in Birmingham to the Orkneys.

[bcw]

Originally Posted by crablab

Did you read my last sentence?

I did. Did you read my post before you quoted it?

Originally Posted by bcw

That would be a massive advantage, but as far as I am aware it is not the case.

I was not aware when I wrote that post that the law had changed. Thank you for providing the link; this is something I will read up on.

[Forfoxake]

Originally Posted by ChickenHouse

ADS-B In/Out could serve perfectly, if not better, than Flarm, BUT physics comes right at the corner. The US already had to introduce UAT to free available bandwidth from 1090ES and if we really would all go for an ADS-B 1090ES solution, the gibberish of all that stations will congest the air. Flarm did overcome some of the restrictions by reducing power, so making the area covered "fit for purpose of the gliders". Now with the new PowerFlarm the advantage gets less ... Same trouble as with radios, as long as we all had 3 to 5 Watts of power, we could reach the next airport and traffic control, now we blow our stumbling with 16 Watts from final in Birmingham to the Orkneys.

Take your point about ADS-B in/out do not think this would be much of a problem as long as the system used mainly warns of imminent collision, which is thankfully very rare. That is why I much prefer some sort of audible warning of a potential collision rather than the virtual radar display being promoted by many. You really do not need to know about all the aircraft near you- only about the ones that are likely to hit you!


PowerFLARM does this with ADS-B and other FLARM/PowerFLARM transmitters but only indicates the close presence of Transponder equipped aircraft (if transponder switched on!). Not sure about PilotAware.


So ADS-B in/out would be much better but is still pretty expensive (and not widely adopted by light aircraft).


In the meantime, I think PowerFLARM is the best solution (or possibly PilotAware), despite the cost. What price do you put on reducing the risk of a probably fatal mid-air collision?


PS Any system that detects ADS-B is better than nothing because nearly all airliners have it. Can you imagine the consequences for GA in the UK if a light aircraft, microlight, gyro, helicopter or glider were to pile into an airliner?

[cotterpot]

Barely a week or two goes by in UK airspace where there isn’t some form of near get-together

I don't see that at all. Any recent evidence?

[abgd]

Any system that detects ADS-B is better than nothing because nearly all airliners have it. Can you imagine the consequences for GA in the UK if a light aircraft, microlight, gyro, helicopter or glider were to pile into an airliner?

How does one pile into an airliner? How does one avoid an airliner? I suspect with considerable difficulty, as it's more likely to be the airliner that does the piling-in. In my hang-gliding days my instructor's advice was that if a military jet came along, one should turn to show them your wing... the thinking being that the speed differential was such that there was nothing you could do to avoid a jet, but if they knew you were there, they might just be able to avoid you.

I imagine a transponder is a more useful tool for avoiding meeting airliners. Even in class-G, someone can usually see you on radar and separate you.

Not saying a system that shows you the airliners is useless... but I doubt it's a panacea either.

[abgd]

I don't see that at all. Any recent evidence?

Ditto. The Kitfox/Cessna 177 accident is the last one I can think of. En-route midairs cause a very small proportion of aviation fatalities. I share the concern re. the risks to GA if someone were to bring down an airliner but mid-air collisions with other small aircraft are fairly low on my list of concerns - well below the weather, carb-icing and all of that.

[Forfoxake]

Originally Posted by abgd

How does one pile into an airliner? How does one avoid an airliner? I suspect with considerable difficulty, as it's more likely to be the airliner that does the piling-in. In my hang-gliding days my instructor's advice was that if a military jet came along, one should turn to show them your wing... the thinking being that the speed differential was such that there was nothing you could do to avoid a jet, but if they knew you were there, they might just be able to avoid you.

I imagine a transponder is a more useful tool for avoiding meeting airliners. Even in class-G, someone can usually see you on radar and separate you.

Not saying a system that shows you the airliners is useless... but I doubt it's a panacea either.

I agree that a Mode C/Mode S transponder (if switched on!) is a better tool at the moment for avoiding a close encounter with an airliner but only because it detects YOU with TCAS and airliners normally operate in a known traffic environment.

However, personally, despite my comments about virtual radar, I find it very reassuring that PowerFLARM confirms that a collision with a nearby airliner is not imminent because of the potential for large loss of life if a collision occurs and the probable resulting massive restrictions on GA in this country. Not that I would probably have to worry about the latter myself!

As you suggest, because of the higher closing speeds involved with jets, an electronic warning system is even more likely to be effective than the Mark 1 eyeball. However, I said that ADS-B detection was "better than nothing" not a panacea.

[Forfoxake]

Originally Posted by abgd

Ditto. The Kitfox/Cessna 177 accident is the last one I can think of. En-route midairs cause a very small proportion of aviation fatalities. I share the concern re. the risks to GA if someone were to bring down an airliner but mid-air collisions with other small aircraft are fairly low on my list of concerns - well below the weather, carb-icing and all of that.

As I said earlier, imminent (mid-air) collisions are thankfully very rare but the results are almost always fatal, unlike many other incidents involving light aircraft.

Since I fly a Kitfox, it was probably the Kitfox/Cessna 177 accident that concentrated my mind on this issue, plus a few close encounters of my own. I think that most GA pilots who have done a reasonable number of hours in uncontrolled airspace will, if pressed, admit that they have come too close for comfort to another aircraft which they did not spot until very late.
And of course, you do not see the one that hits you!

I hate to say this but I came to the conclusion some time ago that "see and be seen" is largely a myth. Because of the natural limitations of the eye, the main reason that there are so few mid-air collisions is because the air is such a big place and there are, relatively, so few aircraft flying in it.

Electronic warning systems have been available for many years (what happened to the strobe detection system being trialled some years ago?) but have not been widely adopted in GA. I think it is about time we got our act together.

[FullWings]

I don't see that at all. Any recent evidence?

UKAB Reports

There are many instances of aircraft getting close enough to “cause concern” to the pilots or ATC. Often, they have some form of electronic conspicuity and/or are talking/listening on the radio but although there is enough data in retrospect to prevent the near-miss, it wasn’t available to assist at the time, e.g. a controller can see two dots converging on his screen (and maybe gets a STCA) but the aircraft aren’t on his frequency; one has FLARM, one has a XPDR; one is on an en-route frequency, the other on SafetyCom and so on.

That’s one of the frustrations: there is a lot of “here I am!” going on but because of the diversity of position reporting and receiving equipment on smaller aircraft, there are many cases of the data to prevent a near miss or collision being available but not collated/interpreted in real-enough time to help...

The Kitfox/Cessna 177 accident is the last one I can think of. En-route midairs cause a very small proportion of aviation fatalities. I share the concern re. the risks to GA if someone were to bring down an airliner but mid-air collisions with other small aircraft are fairly low on my list of concerns - well below the weather, carb-icing and all of that.

There were c.50 Airprox reports in 2016 that were graded at the highest risk category, “A”, in that the separation was small enough it was purely down to luck that the aircraft didn’t collide. Remember this is just from pilot & ATC reports - those that “pass in the night” are not recorded.

There were multiple fatal midairs in 2016, I haven’t researched the exact number but it was significant.

[Forfoxake]

Interestingly, the latest (2015) annual report by the UK Airprox Board states:

GA-GA incidents nearly doubled in 2014 compared to 2013, and only abated slightly in 2015. Depending on one’s perspective, this overall step-increase in GA-GA incidents over the last 2 years is either cause for concern in that GA are having more Airprox or, on the other hand, may be cause to rejoice in the fact that our engagement strategy over the last couple of years is bearing fruit through a greater awareness and willingness to report Airprox. However, notwithstanding the latter perspective, such a marked increase seems intuitively to indicate an underlying issue.

The equivalent AAIB Annual Safety Review for 2015 states:

"Nine of the AAIB’s reported field investigations were into accidents involving fatal injuries. Of these fatal accidents, eight were as a result of Loss of Control inflight (LOC-I) and one due to Controlled Flight Into Terrain (CFIT). Other factors recorded were one accident was a mid-air collision (MAC), one had a powerplant failure (SCF-PP) and one related to fuel (FUEL). Two of the fatal accidents suffered post crash fires (F-POST)."

Also very revealing, from the GASCo Flight Safety Extra:

"Avoiding collisions – a monthly update from Director UK Airprox Board giving some learning themes for recreational pilots.

The Airprox Board assessed 23 incidents during the January 2017 meeting, 7 of these were drone/UAV reports and 16 were aircraft-to-aircraft incidents. Of the aircraft-to-aircraft incidents, a definite risk of collision was assessed to exist for 5 events (1 x Category A and 4 x Category B). Two of these risk-bearing incidents involved aircraft joining the visual circuit (see comments below and the Airprox of the Month) which reinforces the need to fully understand the various join types, adhere to procedures, and watch out for others joining the circuit who you may not have heard on the radio. The other main themes discussed this month were: poor airmanship decisions in 9 incidents; late-sightings/non-sightings in 5 events; and 3 miscellaneous incidents involving simple conflicts where neither pilot was fully aware of the other.

As for the 2 incidents involving aircraft joining the visual circuit, both of these involved a combination of pilots pressing on when uncertain of the position of the other aircraft; assuming another pilot would do something he did not in the end do; pilots not following join procedures (thereby denying others situational awareness of where they might be); and confusion over radio calls that were either missed, or not representative of what the pilot was actually doing. As we have seen before, and especially at airfields with air-ground only, the visual circuit relies heavily on people being predictable (or clearly stating their intentions if they cannot be); robust lookout at all times; thinking about potential conflict points (and especially with respect to non-radio or radio-fail aircraft); and clear communication of intentions.

My Airprox of the month was one of these joining incidents. Airprox 2016210 was a Category A incident involving a PA30 and an RV9 that were both joining runway 27LH at Shobden. The RV9 pilot was joining from the south and conducted an overhead join as he stated on the radio. The PA30 initially wanted to join effectively crosswind from the north but agreed also to conduct an overhead join when requested by the AFISO. Unfortunately, the PA30 pilot then subsequently reverted to a crosswind join rather than flying through the overhead, and the 2 aircraft came into proximity near the upwind threshold. The PA30 pilot was of course perfectly entitled to join crosswind, but should have made his revised intention to do so clear to all, and should have avoided the RV9. The full report can be found on the UKAB website at (Welcome to the UK Airprox Board | UK Airprox Board) in the ‘Airprox Reports and Analysis’ section within the appropriate year in the ‘Individual Airprox reports’ tab."

[bcw]

I think we are going a little off-topic here!

[abgd]

It's nonsensical to talk about solutions if discussion of the problems is off-topic.

I hate to say this but I came to the conclusion some time ago that "see and be seen" is largely a myth. Because of the natural limitations of the eye, the main reason that there are so few mid-air collisions is because the air is such a big place and there are, relatively, so few aircraft flying in it

This is true; as you probably know there's been a lot of proper research done that confirms your view. Theoretical studies. Practical experiments with 2 aircraft where they sit a pilot as a passenger, and fly the second aircraft around and ask the pilot-passengers to record when they see it. All of it confirms what you say: a good lookout only slightly reduces your chance of a midair collision because you don't see most traffic.

My own view is that a good lookout remains helpful around airfields where you can predict - more or less - what paths the aircraft are going to take. That means you can focus your attention on the most dangerous regions.

As for the number of near-misses - I'm not particularly impressed. As the numbers of mid-air collisions are low, anybody trying to study them will do well to look at near-misses, which are more frequent. For example, if there were to be lots of near-misses in the Luton/Stanstead corridor this would be a good indicator that something ought to be done to prevent a future accident. However, if you say 'it's true that over a period of X years, mid-air collisions make up only Y percent of fatal accidents - but look how common near misses are', this doesn't make mid-air collisions any more of a risk.

It's true that midair accidents are often fatal when they happen, but even then they are infrequent enough to be rare causes of fatalities. The issue with yet another box of tricks is that it's potentially yet another thing to distract our attention from the important things in aviation.

This isn't to say that I'm against the idea. If the signal to noise ratio is low enough - i.e. it only distracts you when evasive action is actually required - then why not? And in the future I think we will need tools to enable us to share airspace with drones.

I think part of the reason mid-airs capture our imagination so much is that psychologically we like to think we can handle emergencies such as an engine failure or inadvertent IMC - even when this may not be the case. The idea of colliding with another aircraft then being a passenger all the way down though, is horrifying.

[crablab]

I think mid-airs with drones are more frequent than other aircraft at the moment!
Although saying that there was the PA-28 collision in the London vicinity which only serves to reinforce the requirement for especially good lookout under the LTMA.

Only one had Mode S and although that doesn't necessarily provide ADS-B most have ES which does broadcast on 1090Mhz albeit with only altitude information. Report here

[Forfoxake]

Originally Posted by abgd

It's nonsensical to talk about solutions if discussion of the problems is off-topic.

This is true; as you probably know there's been a lot of proper research done that confirms your view. Theoretical studies. Practical experiments with 2 aircraft where they sit a pilot as a passenger, and fly the second aircraft around and ask the pilot-passengers to record when they see it. All of it confirms what you say: a good lookout only slightly reduces your chance of a midair collision because you don't see most traffic.

My own view is that a good lookout remains helpful around airfields where you can predict - more or less - what paths the aircraft are going to take. That means you can focus your attention on the most dangerous regions.

As for the number of near-misses - I'm not particularly impressed. As the numbers of mid-air collisions are low, anybody trying to study them will do well to look at near-misses, which are more frequent. For example, if there were to be lots of near-misses in the Luton/Stanstead corridor this would be a good indicator that something ought to be done to prevent a future accident. However, if you say 'it's true that over a period of X years, mid-air collisions make up only Y percent of fatal accidents - but look how common near misses are', this doesn't make mid-air collisions any more of a risk.

It's true that midair accidents are often fatal when they happen, but even then they are infrequent enough to be rare causes of fatalities. The issue with yet another box of tricks is that it's potentially yet another thing to distract our attention from the important things in aviation.

This isn't to say that I'm against the idea. If the signal to noise ratio is low enough - i.e. it only distracts you when evasive action is actually required - then why not? And in the future I think we will need tools to enable us to share airspace with drones.

I think part of the reason mid-airs capture our imagination so much is that psychologically we like to think we can handle emergencies such as an engine failure or inadvertent IMC - even when this may not be the case. The idea of colliding with another aircraft then being a passenger all the way down though, is horrifying.

Your point about drones is important. You have virtually no chance of spotting a small drone with your eyes if it is going to hit you. However, I fear that even if electronic conspicuity is made mandatory for drones soon, there will still be lots of illegal ones (*) around so we will have to depend again on the air being such a big space.

Your point about another distraction (in the cockpit) is also well made. That is why I dislike a sophisticated virtual radar display. A simple display that can be included in the visual scan plus some sort of special warning (for example an increasingly urgent audible tone into your headset in a powered aircraft) of an imminent collision is much better imho.

(*) The BBC website reports today that "A passenger plane had a near-miss with a drone at 10,000ft as it approached Heathrow Airport.....Large drones are not permitted to fly above 400ft (121m) or within proximity of airports or airfields. It happened on 11 November 2016, so quickly the Airbus A320 pilots said they had "no time to react"..... It was one of four near misses between aircraft and drones in the latest UKAB monthly report, and brings the total in the past 12 months to 59."

[Forfoxake]

PS Why do most people persist in calling such incidents a near-miss.
A near-hit would be much more accurate!