Peter wrote:
A GNS box has no “VFR/IFR” config, so this is doubly bizzare. I suspect the reason was a subtle one, along the lines of the issue here. Did the installer do the DER package design, used a US based DER, or did they buy the DER 8110 from another shop? I wonder if @wigglyamp could shine some light on what the reason might have been?
As far as I’m aware, an 8110-3 from a DER is specific to one aircraft serial number, so can’t be bought by another installer and just used as-is. This is certainly the case for the DERs we have used – both for structures and systems.
You are correct that there is no specific VFR/IFR configuration for the GNS. Provided it’s installed and tested to the installation manual then it’s certifiable for IFR and will then use the Garmin-supplied template AFM supplement. It’s important to remember that the original FAA STC certification for the GNS was just on a PA32 – no AML, so each subsequent aircraft (we’re taking N reg here) needs an individual approval whether it’s a field approval, a DER 8110-3 or possibly even a separate STC, and this process includes final approval of the AFMS.
The GNS certifications in Europe pre-date EASA, so there are multiple national approvals available. Surprisingly, the German LBA validated the FAA PA32 STC and cleared it for all Part 23 aircraft, so at a stroke made a very useful AML! UK CAA were not pleased if we quoted this in documentation once EASA came into force!
an 8110-3 from a DER is specific to one aircraft serial number, so can’t be bought by another installer and just used as-is.
I have never done this but AIUI that is correct. If it is to be re-used for another job, and even if the job is identical to previous, it may be necessary to pay the DER more money if he retains copyright, rather than put tippex over the aircraft reg and s/n 
Field approvals are the same – airframe S/N specific.
However, with the DER 8110, a Field Approval and even an STC, you can reference the data (not the 8110 or the field approval or the STC itself – just their contents) as acceptable data supporting another Field Approval. This was done here where the FA was prepared and submitted for me by an FSDO inspector. That job, for a TB20, referenced among other things (the full details are in the writeup) a Cessna 421 STC which was the only STC that Sandel ever had for the SN3500. Same as the KLN94 really – there is some Piper STC and everybody else had to do a FA.
And if you do this, there is no need to communicate with whoever prepared the other approvals; all the required stuff is on the FAA public-domain record. You are not copying it; you are merely referencing it.
But you still need somebody to present the 337 + data to an FSDO inspector on your behalf, and that is the hard bit for European pilots. The preparation of the package can be done by any individual who knows the process and has an A&P/IA who can stick his name on the 337 in the application. Actually any A&P/IA ought to know how to do it, but most don’t.
The GNS certifications in Europe pre-date EASA
The one Michael refers to seems to have been done in 2001 which is really early days for a GNS530.
Peter wrote:
But you still need somebody to present the 337 + data to an FSDO inspector on your behalf, and that is the hard bit for European pilots. The preparation of the package can be done by any individual who knows the process and has an A&P/IA who can stick his name on the 337 in the application. Actually any A&P/IA ought to know how to do it, but most don’t.
If you go through an EASA Part 145 maintenance organisation that also has FAA approval then they can raise the 337 without having access to an IA. With the increased access to AML STCs, we don’t often need to get data approved but if we do, we still use DERs rather than trying to get a FSDO field-approval.
Sure, but finding an IA is not an issue. Maybe I am fortunate there.
And yes, modern light-GA avionics mostly go in under an AML STC, which drastically simplifies the whole process. Like my full TKS system – the paperwork is trivial because there is a TB20/21 STC.
It is the awkward buggers (like me) who are installing the less common stuff who need a Field Approval or the DER 8110 route
The DER route is hard to do unless you are going via one of a very small number of avionics shops (the vast majority of them don’t know this stuff and don’t want to get involved) because few if any DERs will work directly for an aircraft owner, or for a lone A&P/IA. Or they are really pricey – I was quoted $10k, plus a list of virtually impossible to fulfil conditions (e.g. a full wiring diagram for the whole aircraft, which doesn’t exist for any Socata) by a DER for the Sandel SN3500. My view was that it was his way of saying he doesn’t want this business unless he can make a lot of easy money. Yet this DER specialised in Sandel products.
I posted the above just to help some people out. It’s not going to be a big business for anyone because, as you say, the market is getting more streamlined by people going for common boxes with STCs.
wigglyamp wrote:
If you go through an EASA Part 145 maintenance organisation that also has FAA approval then they can raise the 337 without having access to an IA. With the increased access to AML STCs, we don’t often need to get data approved
Correct on both counts and why trying to install a used, non-WAAS GNS unit is a waste of time – much easier/better just go with the AML !
Me thinks that the “VFR only” placard on the DER/8110-3 install I’m looking at is do to lack of AFMS and a proper Flight test, both of which are easily corrected.
What year was that GNS530 installed?
Peter wrote:
What year was that GNS530 installed?
You were correct: 2001
Why ?
It was the state of the art box then; no W version.
Peter wrote:
It was the state of the art box then; no W version.
Yes, that I know, but seems rather silly to spend all that money and not be able to use it for what it was made for: RNAV !
I agree but to be fair, in 2001, RNAV as a legal concept didn’t exist, the then trendy job creation scheme was probably PRNAV which almost nobody understood, GPS approaches didn’t exist in Europe…
This customer, like most, would have done what the installer (who is not on EuroGA, BTW, although they do read it because they once threatened legal action over some post) told him he needs, and got his cheque book out. I know the company and in my involvement with them found them having only a very basic capability and that was more than a decade after this job.
A Field Approval would have been the other option but, as I say above, probably as hard then as today. The FSDO business was handled by the NY IFO which has never been supporting these services to GA. Accordingly the DER 8110 route came into common use by avionics shops because it is predictable: the shop does the basic design, liases with a US based DER who signs it off at a rate of (according to one report) $300 per page, and the package is sent off with the 337 to Oklahoma for filing. The customer gets a bill which IME starts at 2k. Nowadays the 8110 data can be used to apply for an EASA STC which is a bonus for the shop which can sell on that STC to other (less clued-up) shops.
The Field Approval route – IF you can get it to work – is great for the proactive aircraft owner who wants to install something and has a good guy/team which can do it.
