Peter wrote:
It is actually a very interesting Q whether this EASA “fear” of a dual GNS failure killing both boxes is still applicable to one GNS and one non-GNS box.
It just shows how clueless are people involved in defining such regulation.
Pirho wrote:
I would never have thought having two boxes from the same family would be an issue.
And it’s not an issue – just take G1000 as an example.
I haven’t read the whole thread, but our current aircraft relies on two GNS430 units. I can also think of about 5 aircraft I previously flew both privately and commerically that had various combinations of 430 and 530 boxes. I would never have thought having two boxes from the same family would be an issue.
I’m afraid I have no further information. I ended up replacing my 430 with a 530W, and then adding a Trig radio as backup, so two radios in total, and not three.
Howard
The initial post references a 3rd COM requirement. One could ask @Howard for more info…
But perhaps no longer applicable to newer (non-GNS/GNSW) boxes? I might ask Socata about the other questions.
Peter wrote:
So the dual-GNS STC which required a separate (third) radio was done by somebody else. Who was that?
There are quite a few dual GNS STCs listed by EASA – no AML versions, and nothing in the descriptions to suggest they had to have the third Comm fitted. I had heard that some German companies were pushed down that road by the LBA but were doing the dual GNS as a Minor change and had to do the third Comm to avoid an STC.
We achieved dual GNS certification in quite a few Part 23 aircraft under Minor changes (both as direct UK CA-approved Minor mods prior to EASA and later also under our Part 21J). The hassle one for me was on a Citation 500 when a particular UK CAA expert pushed the third Comm issue and we spent a long time arguing about it. I won in the end!
I then misread your post above.
So the dual-GNS STC which required a separate (third) radio was done by somebody else. Who was that?
And has this issue gone away for
I also wonder how exactly Socata got their 2×GNS430 option (which sadly I didn’t choose in 2002 ) approved, presumably by the DGAC? IIRC, they also had a 430+530 option available.
Peter wrote:
@wigglyamp did the original “extra radio” STC.
Wigglyamp certainly did not do the ‘Extra radio STC’. As I said in an earlier post on this subject, my STCs claimed credit for other existing systems (transponder, DME) to mitigate a potential dual GNS failure and these arguments were accepted by EASA..
It is actually a very interesting Q whether this EASA “fear” of a dual GNS failure killing both boxes is still applicable to one GNS and one non-GNS box. In the past, before Avidyne came along with the IFDs, if you wanted two modern navigators they had to both be GNS.
Thinking about my last Q, I vaguely recall Avidyne have an STC for two, but I am not sure. @steveavidyne will know.
@wigglyamp did the original “extra radio” STC.
Peter wrote:
Is this dual GPS installation issue still current under present EASA regime?
FWIW, I know about one SE-reg which was equipped with a used GNS430 and a new GPS175 (Garmin’s simplest SBAS navigator) last year, both hooked up to dual G5. At least the avionics shop had no problems with that.
Is this dual GPS installation issue still current under present EASA regime?
Is it also applicable to Avidyne?