I find it a “stretch” to argue that
I accept the first two points (well, to the extent of the equipment actually going in, e.g. does installing a 2004 GTX330 need the latest (2017, say) IM and the 2004 IM would not be legal?) but to argue the rest would imply that any existence of the current data away from the mfg website is somehow not a “real existence” 
There is an argument, in other scenarios, that any printed copy is “uncontrolled” and cannot be used for anything real. But an installer may be working from a printout and not have a laptop running in the plane he is working on. So the installation would be illegal. And what if a dealer gives someone a copy of the PDF?
It quickly gets totally absurd.
Also the reality is that a huge amount of installations are done around the world by non dealers; are all these illegal?
That’s why I wrote (generally): while some Annex 1 planes are certified, generally, they are not (generally, they are homebuilt/vintage etc)
alioth wrote:
Annex 1 (generally) doesn’t need STCs so the whole thing is pretty much irrelevant. Garmin, at least, provides installation manuals for anything you want to put in non-certified aircraft.
That would be up to the national authority to decide, but lots of Annex 1 aircraft are certified and have an ICAO-compliant CoA. For those I expect the modification approval (e.g. STC) requirement applies.
Peter wrote:
There must be exemptions on all this for Annex 1 (non Part 23 etc).
Annex 1 (generally) doesn’t need STCs so the whole thing is pretty much irrelevant. Garmin, at least, provides installation manuals for anything you want to put in non-certified aircraft.
wigglyamp wrote:
Even Avidyne’s statement says that the data is available on their technical publications pages. You can’t access those unless you’re a dealer and have been issued with a log-in. Garmin’s dealer installation policy is pretty much identical to every other manufacturer.
Agree, and Garmin does not restrict the STC permission to use to its dealers, but you would have to get a copy presumably from a dealer as it is on the dealer website.
Even Avidyne’s statement says that the data is available on their technical publications pages. You can’t access those unless you’re a dealer and have been issued with a log-in. Garmin’s dealer installation policy is pretty much identical to every other manufacturer.
Agreed; the A&P will sign off on it.
Same under EASA; you don’t need to have any qualification to do the actual work.
There must be exemptions on all this for Annex 1 (non Part 23 etc). Garmin have gone public with that option in the US but would not reveal details.
Peter wrote:
But DIY installs cannot comply with the STC requirement unless you get permission from Avidyne.
I don’t see why not. If you’re an N-reg owner installing under the supervision of an A&P, then you are an approved installer as far as the FAA is concerned.
In the US context, definitely every A&P, because avionics work is under “airframe” and totally within A&P privileges.
In the European context, I’d think an EASA66 (or the post brexit CAA version) would also meet that.
But DIY installs cannot comply with the STC requirement unless you get permission from Avidyne.
“All National Aviation Authority approved installers” having access to the Avidyne STC must surely mean every licensed A&P? If so, that’s quite a shot across Garmin’s bow, and a more acceptable way of doing business.
