mooney75 wrote:
50% of GA in Europe today have FLARM
Can you provide the source for this info?
I have seen that info circulated in many places. A quick Google search comes up with this at least official-looking page (but seems to be old):
https://support.flarm.com/hc/en-us/articles/360008584593-How-many-aircraft-have-FLARM-
I can offer one data point: a few years ago I borrowed a Flarm box and flew with it for about 6 months, and it didn’t pick up a single aircraft.
Admittedly I wasn’t flying near glider sites…
I also find, to my slight surprise, that a lot of gliders doing x/c flights are carrying Mode C (maybe Mode S but I can’t tell) which shows up nicely on my TAS605 – azimuth, relative height and distance.
Note that the TAS605 is “TCAS” but TCAS1 not TCAS2; the two are being confused in this debate, with TCAS1 being highly useful for all OCAS traffic avoidance. And most modern “IFR tourer” planes have TCAS1, factory installed. A small % of them also have ADS-B IN/OUT.
Anecdotally, from pilot feedback, Flarm usage in powered GA is bigger in some places in Europe e.g. Germany. But not the UK.
I have been flying with FLARM for many years. Maybe around half the aircraft I see are either powered aeroplanes or helicopters. I often fly in continental Europe though. But the collision warnings I have received in the UK have been only with powered aircraft (of which one helicopter).
mooney75 wrote:
I have seen that info circulated in many places. A quick Google search comes up with this at least official-looking page (but seems to be old):https://support.flarm.com/hc/en-us/articles/360008584593-How-many-aircraft-have-FLARM-
I still seriously doubt 50% of GA. If there were 35.000 installations in 2017 (manned aircraft) and from GAMA report there’s some 140.000 GA aircrafts in Europe (not including non-powered gliders – main users of FLARM), it’s easy to calculate that 50% is big big over-estimate.
The GAMA report includes many biz jets, so my guess is that those are included from the 50%. Whatever GA means…
Not really a factor… If you look at this (admittedly long, but most informative threads are not short) thread you will find some numbers for airframes around Europe.
For example the UK has about 20k GA planes, IIRC.
It is quite impossible for anywhere even remotely near 50% of European GA to have Flarm. That many boxes have not been built and shipped, otherwise it would be a huge company 
It is well possible that a specific glider community in Germany is well Flarm equipped.
IMHO, this ship has now sailed, ADS-B will be the only way in the long run, and the wide range of other boxes exist only because
and this is hugely obvious from reading the UK sites. They are also full of posts by industry players who should know better – example. It is pretty depressing to read. But the reality is that a lot of e.g. Skydemon users don’t know how to config the program correctly (yeah; one gets beaten up for posting that) so there is no chance of this issue being understood any better.
I have been using a Power Flarm, which does all 3 modes:Flarm, ADS-B and Mode C, where in the latter it will only give vertical separation.
Personally, I would not like to fly without at least the latter two anymore I´ve not had a lot of Flarm alarms, but I´ve had LOTS of mode C resolutions and quite a few ADS-B alerts. The most important thing is that these devices can give you a vertical information, e.g. how much above or below you a target is. So even if you don´t spot it immediately, you still get a good idea about the altitude difference and can react accordingly.
For me, clearly, ADS-B is the future. FLARM was a valiant and necessary attempt of self help originating from the glider community, which however has caused a system confusion. That is why in my view, only systems which can detect all sorts of trafffic make sense.
Personally, I’m very confident that the ship has sailed for ADS-B. Except for aircraft > 5,700 kg, almost nobody transmits it. It’s also not very useful for collision avoidance. It was intended for ATC as a replacement for SSR, but wasn’t good enough even for that purpose. I suggest reading about ADS-B and FLARM before making comments like “ADS-B is the future”. ADS-B is just a transmitter (that nobody is using). FLARM is both a radio protocol and a collision-avoidance system. So even if you have ADS-B Out/In, you still need FLARM for the collision avoidance part.
FLARM is today very big in powered aeroplanes, helicopters, drones, paragliders, etc. To think that a significant part of these would install any type of ADS-B is ridiculous.
It’s also not very useful for collision avoidance.
Mooney75 – I don’t think you are familiar with certified TCAS1/TAS systems – example
They are made by Garmin, L3, Avidyne and older ones by Honeywell, and are pretty common on newer IFR tourer aircraft. See various threads here on these systems; the search box finds them. Garmin and L3, and upgraded Avidyne can also display ADS-B emitters. These display only SIL=1 or higher emissions, which for the “portable” emitters is just SkyEcho2 when configured for SIL=1 which I am not sure is legal outside the UK. On the UK sites everybody is skirting around TCAS1, pretending it doesn’t exist, because it is in the interests of certain businesses.
