Peter wrote:
It is still in theory illegal unless you are 250kt+ etc and one UK avionics shop (Lees) wrote openly some years ago that (paraphrasing) they had to rip out large numbers of the interconnections which made the installations illegal.
I don’t think that is true. It is mandatory at 250Kts+ that does not make it illegal below does it? There are many approvals which allowed the installation of ADS-B out on a non WAAS GPS. Later EASA changed that for new approvals, requiring WAAS GPS.
From the German aircraft which I do testing on, most of them are equiped with some form of ADS-B out. The transponder will also send information on the GPS used (often set in configuration). Such that you can have no compliant ADS-B out installation, which are still very useable for traffic avoidance on for example TRX1500 / TRX2000 / Power Flarm systems.
Typically with the transponder on ALT it will do mode A (squawk), mode C (altitude) mode S (additional data depending on aircraft). Likely they do mode S only to keep track of multiple aircraft. You can have multiple aircraft which squawk 7000 and can be on the same altitude. It would be difficult to keep track of these if you don’t have a sense of direction. When you know the unique 24 bit adress you will be able to keep track of them.
I sort of understand but since none of this gives azimuth, what do they gain by restricting it to Mode S aircraft?
I suppose they can say “5 aircraft known at your level” versus “1 or more aircraft known at your level” but if you can’t see the direction, all you can do is climb or descend and hope that they didn’t see you so they continue at their previous level.
I don’t think that is true. It is mandatory at 250Kts+ that does not make it illegal below does it? There are many approvals which allowed the installation of ADS-B out on a non WAAS GPS. Later EASA changed that for new approvals, requiring WAAS GPS.
I have an old reference here Probably, nobody cares about this anymore.
Peter wrote:
Why FLARM is encrypted is incredibly stupid. It’s a market grab – get it adopted, with lots of addicts, and then screw them. What other motive could there be?
Well, I think this is how most big companies play their game :-(
Peter wrote:
I wonder how can that be
My understanding is that with mode A/C only the interogator (ground SSR or TCAS) knows if the a/c transponder is answering its sqawk code or altitude. So PFLARM and co need to make some educated guess if they want to show the Mode C a/c. With mode S it is easier because the transponder answer tells you what was the question.
Peter wrote:
I have an old reference here Probably, nobody cares about this anymore
That doesn’t say it is not allowed for others does it? It says is is mandatory for aircraft over 5700 kg and/or over 250 Kts.
Aircraft which are only required to provide Mode S ELS, but which can provide one or more EHS parameters are not required to
seek a Mode S EHS exemption from Eurocontrol.
You get an non complient installation.
For an RV7 I would (am) do nothing until the new pilot aware product has been released.
For an RV7 I would (am) do nothing until the new pilot aware product has been released.
That is a completely different thing. The original poster wants a proper TAS system that will show all current transponding aircraft.
It’s a great initiative, but PilotAware will always be a niche product like FLARM.
vic wrote:
As far as I know it is not EASA requiring a “certified” GPS unit for ADS-B out,
It is for certified ADS-B out. A non certified GPS as source has been accepted, and rejected depending on regulations (this has changed from time to time)
CS-STAN subsection CS-SC002a – the one about mode s – says:
However, the voluntary transmission of additional ADS-B data (e.g. GPS position and velocity) can be accepted when the position and velocity quality indicators report lowest quality, the equipment manufacturer has stated compatibility with the directly connected GPS source, and the transponder is not
authorised according to ETSO C166b or equivalent.
Which would be great, but the requirement for the transponder to NOT be covered under ETSO C166b would make this much less usable, right? As in, most anything with mode S would be ETSO C166b? The Trig stuff seems to be.
