FLARM - equipment options and how well does it work around Europe?

turns out that the “person” (I usually use a different term when recounting this story) in charge of the second plane was flying in loose formation, in crowded restricted airspace, without a transponder fitted, so nothing except eyeballs would have seen him.I get high blood pressure just thinking about his recklessness…and you’ll appreciate of course that he didn’t see me until very very late…closing speed of more than 230mph.

There is quite a bit of non transponder traffic out there. While I agree having a transponder is a good idea, I am not sure I would see the absence of one as reckless.

Howard wrote:

It turns out that the “person” (I usually use a different term when recounting this story) in charge of the second plane was flying in loose formation, in crowded restricted airspace, without a transponder fitted

Do you know for certain the aircraft didn’t have a transponder? It’s quite normal for only the lead aircraft in a formation to squawk. You’ll often hear ATC giving the instruction “lead aircraft squawk xxxx”.

It sees much more traffic than the Zaon : ADSB, Flarm, and Transponder traffic. The Zaon only sees transponder traffic.

Problem: In UK powered GA almost nobody is radiating FLARM or ADS-B. Which leaves you… ? The reality here is that detecting Mode C is simply the best method, by a factor of maybe 100×. The problem with that is that it costs about £12k and evidently very very few installers are capable of installing it without doing a right hash of it. And I am pretty damn sure that the Mode C prevalence applies to most busy GA communities around Europe. ADS-B is only just starting to become talked about (a few IFR diehards are installing it, after LPV) and FLARM is highly localised. The UK has about 20k GA planes and I would be astonished if even 1% has ADS-B.

It shows the position of Flarm and ADSB traffic brilliantly. I now actually see the gliders and ADSB traffic out the window, from my cockpit.

What sort of ADS-B traffic do you see?

The Powerflarm however does not show position for transponder-only traffic, whereas the Zaon XRX device allegedly did so within about 45 degrees….but in fact I never found the Zaon to be very accurate and much of the traffic that it allegedly detected I could not see from the cockpit.

ZAON have also gone bust… yes it did just the four quadrants.

The height is computed from the other plane’s broadcast mode-C height information which may be a hundred feet or so out of course, but that’s close enough.

It’s all you get with any system, unless GPS altitude is used.

much of the traffic that it allegedly detected I could not see from the cockpit.

That is normal anyway. I could put three ex RAF people in the cockpit and fly around under the LTMA and I bet you that 50% of the TCAS targets would never be spotted.

There is quite a bit of non transponder traffic out there. While I agree having a transponder is a good idea, I am not sure I would see the absence of one as reckless.

It’s not legally reckless but if I see a plane which obviously has or could have a transponder (say, worth 100k plus), but it doesn’t show up on TCAS despite passing within 100m of me, then I say to myself that the pilot is at best pretty irresponsible. We all share the same sky and have to make the best of it. And I am sure many fly like that deliberately, for all kinds of reasons, not always to do with the ability to bust airspace from underneath.

@fattony I know for a fact that the other plane concerned had no transponder fitted, and he wasn’t flying in formation with the other plane. At best it was a ‘loose formation’. The Airprox investigation quickly found out about the absence of a transponder. You can imagine the view of Airprox investigators, air traffic controllers and other involved in air safety of planes that fly in crowded airspace without even a transponder. (I’m with them on this.)

Peter wrote:

What sort of ADS-B traffic do you see?

I see mostly CAT planes, flying a few thousand feet above me, where such information is entirely irrelevant, but every so often I see a GA plane broadcasting ADSB-out. I am hoping that more and more people will start fitting ADSB-out transponders as they replacement cycle rolls around. These new devices from Garmin look like a perfect solution. Garmin’s new GTX 335/345 ADSB-out transponders

Howard

Howard, how does the mode c traffic display on the 795 when you habe no azimuth?

I would confidently predict that we will all be dead before the part of UK GA which is most likely to hit you will be equipped with ADS-B or FLARM or anything else beyond Mode C.

The sort of pilots who buy the gear are not that likely to be flying through the really busy spots, doing weekend burger runs. They tend to fly as high up as they can get clearance for, or fully IFR in CAS.

Mode C has been around for much longer than I have been flying and still maybe 50% of the sub-2000ft traffic is not visible, and I am sure they have no plans whatsoever to do anything about it. Many are homebuilts based on strips and thus pretty well outside “the system”.

Unfortunately what this means is that there isn’t actually a good solution. Not everything in life has a solution Well, you can get a fairly good solution for the 12k I spent (just choose the installer carefully!) and by flying above 2000ft if at all possible.

That said, most UK mid-airs have been near aerodromes, but there you get all the traffic concentrated so a fairly good % is Mode C. And there I really do act on traffic warnings, often getting out of the circuit or the vicinity of the aerodrome even though ATC is not aware of the traffic.

Peter wrote:

It’s not legally reckless but if I see a plane which obviously has or could have a transponder (say, worth 100k plus), but it doesn’t show up on TCAS despite passing within 100m of me, then I say to myself that the pilot is at best pretty irresponsible. We all share the same sky and have to make the best of it. And I am sure many fly like that deliberately, for all kinds of reasons, not always to do with the ability to bust airspace from underneath.

Sure but in the case Howard describes we are talking a non-txpdr aircraft which is not particularly expensive (R200).

Howard wrote:

but every so often I see a GA plane broadcasting ADSB-out. I

As have I which works beautifully. I had an excellent traffic pickup using ADS-B into Cranfield that helped me avoid and join in trail. But most aircraft don’t have it and while a greater proportion have traffic systems, most aircraft still don’t. See and avoid remains the primary means of avoiding collision OCTA.

While I wish everyone had ADS-B out installed that is not going to happen in the foreseeable future. An additional problem I see is people with traffic systems (like myself) assuming that they see all the traffic. Easy to get head down and forget to look out the window. Traffic systems are a useful aide (as is a traffic service) but as in Howard’s case even a traffic service would not have seen the aircraft concerned.

Sir_Percy wrote:

how does the mode c traffic display on the 795 when you have no azimuth?

Sir Percy, the Garmin displays a circle with height data, with the radius being the distance of the detected plane, but no mark on the circle to identify where the plane is on the circumference. As the plane gets closer, the radius shortens….The Powerflarm display does the same. As you imagine, this means : threat somewhere on this circle, at the height shown.