This is copy pasted from the Facebook post by Mark Wittmayer on the topic (after he did a one off IFR modification for his GCAA).
"When I had questions about my 7GCAA’s IFR certification, I did the following:
- I first called my local FSDO in Orlando. They said that they really didn’t know about this type of aircraft and IFR certification. They then told me to call the Aircraft Certification Office (ACO) in Atlanta.
- I called the Atlanta ACO and they were very nice but said that they would prefer I ask about such an aircraft with the FSDO up in Milwaukee because they are the experts with American Champion aircraft.
- I called the Milwaukee FSDO serving ACA and they referred me over to one of their people named Peter Corrao. So I called and chatted with Peter. This guy is the real deal and knows what he’s talking about. I would suggest you write or call him. Here’s his office contact info:
Peter Corrao
Aviation Safety Inspector
Milwaukee Flight Standards
District Office
[email protected]
414-486-2952
Peter may even be able to run your IFR paperwork, such as a 337 or single aircraft STC, through at his office for approval.
As a further reference, there is an 8KCAB Super Decathlon owner named Ken Bowersox, (retired astronaut, nice guy) who got his airplane IFR certified with an ACO. I chatted with him and here’s what he had to say about it:
I applied for a single aircraft STC with the closest FAA Aircraft Certification Office – not a FSDO…
Helps to call them first and that can take a little time before you get one of their engineers on the phone.
Once you’re application is in the system, the ACO will assign a rep to your case.
The ACO rep has a lot of flexibility in what they can approve. My rep required equipment that was beyond the equipment for an IFR 7GCBC – which can be factory certified.
In addition to pitot heat, gyros, lights and IFR instrumentation, was required to do the following:
Add a standby static source
Add a second attitude reference
Install new limitations decals that included IFR flight
Test the current draw of all the electrical equipment, and verify the installed battery could power the systems for the required amount of time in an emergency.
Assemble a flight manual supplement which listed minimum required equipment for the STC and new operating limitations, which included IFR operations.
Once the rep had a chance to inspect my airplane and sign off on all the paperwork, the FAA granted an STC which modified the operating limitations from the original type certificate to allow IFR flight.
Well I hope this all helps. Good luck!"