Experimental Exhibition Sailplane: Modifications, Add Self-Launch Engine

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Sailerboy

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If a sailplane is registered as "Experimental Exhibition" can I maintain and modify it the same as an "Experimental" home built sailplane that I purchase? Is it possible to retrofit an "Experimental Exhibition" sailplane to add a self launch engine (talking about the paperwork side, not the engineering and construction side). Or does the "Exhibition" adder effectively limit my options?
 

TFF

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No. You have to have a DER sign off on the major modifications. It also has to be renewed every year.
 

skydawg

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I don’t think you need a DER sign off if already registered as experimental unless there is something specific in op limitations. Typically for ex exhib limitations will state if modifications are made that may impact flight characteristics it must be put back into phase 1 flight test restrictions as noted in op limitations Until it’s proven safe to again return to phase 2.

if you were applying for initial experimental cert, FAA can require you to have a DER sign off on something, but once issued, your op limits will list what’s required....this is my experience at least.

as far as being signed off by FAA each year, this is not normally the case. unless the aircraft has very unique features, exhibition only requires a yearly condition report from an A&P and updated program letter. However, if the aircraft was originally certified, regardless of how long ago, it must be maintained as a certified aircraft Per part 43.

hope this helps.
 

TFF

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Rules are rules. Interpretation is subjective. As long as you can get them to sign the paperwork... Part of the reason they want you to go to a DAR/DER. FAA employees don’t want to be on the hook. Those are internal problems of the agency, not the actual inspectors wanting to help.
 

proppastie

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My IA once called the Philly Fisdo (reportedly the worst in the nation) to ask a question, and the response was "you are an IA....figure it out yourself" ....Try to get the answer in writing ....good luck with that.
 

Marc Zeitlin

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If a sailplane is registered as "Experimental Exhibition" can I maintain and modify it the same as an "Experimental" home built sailplane that I purchase? Is it possible to retrofit an "Experimental Exhibition" sailplane to add a self launch engine (talking about the paperwork side, not the engineering and construction side). Or does the "Exhibition" adder effectively limit my options?
As an A&P, my answer is "yes, you can maintain and modify the aircraft the same as an Amateur Built Experimental". However, you cannot sign off the Condition Inspection - only approved people (per FAA Order 8130.2J, Table D-1, number 19) can do that.

Obviously, adding an engine to a sailplane would be considered a Major Change, per 14 CFR Part 21.93, so we then go to Table D-1, number 22 for the limitation that will be in the Operating Limitations (if the OL's were issued within the past few years - they could say just about anything if they're older, but reading them will tell you what you need to do) with respect to MC's, and it says:

The geographically responsible FSDO where the aircraft is based must be notified, and its response received in writing, before flying this aircraft after incorporation of a major change as defined by § 21.93. The FSDO may require demonstrated compliance with § 91.319(b).​
So, you need to tell the FSDO that you made a major change, propose a new test area, and get their response in writing regarding the test area (there is nothing in here that requires an inspection of the airplane or approval of anything you've done). As the last sentence states, they may require demonstrated compliance with 91.319, so taking good data during the test period is critical so that you can prove that you've done that.
 

BBerson

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The geographically responsible FSDO where the aircraft is based must be notified, and its response received in writing, before flying this aircraft after incorporation of a major change as defined by § 21.93. The FSDO may require demonstrated compliance with § 91.319(b).So, you need to tell the FSDO that you made a major change, propose a new test area, and get their response in writing regarding the test area (there is nothing in here that requires an inspection of the airplane or approval of anything you've done). As the last sentence states, they may require demonstrated compliance with 91.319, so taking good data during the test period is critical so that you can prove that you've done that.
Hmmm. Does that mean notification before a major change is not expected or common?
What if the FAA has a concern about the change after the fact?
 

Marc Zeitlin

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Hmmm. Does that mean notification before a major change is not expected or common?
Certainly in the E-AB world, it's uncommon (if it ever happens) and not expected - I've never heard of anyone asking the FSDO for permission for a MC - only notification after the fact, but before flight to get approval for the test area. Since they have no jurisdiction to approve or reject any Major Change to an E-AB (or, it seems, from 8130.2J an E-Exhib.) aircraft, there's no reason to ask for it. It clearly states that you have to get a written response, but it also makes it clear that you ask for their response AFTER incorporating the Major Change. The only thing you need to ask for approval of is the test area, at least for E-AB aircraft. Exactly what the "response" from the FSDO is isn't totally clear for an E-Exhib. aircraft, but by looking at the verbiage in the E-AB MC rule in Table D-1, #23, one can see that the restrictions on E-Exhib. aircraft are LESS stringent than those on E-AB aircraft - not more.

What if the FAA has a concern about the change after the fact?
Then they will tell you that you're only allowed to fly over a totally uninhabited area, and they'll restrict your test area to something they think doesn't endanger folks on the ground, and give you a longer test period (25 hours, maybe, instead of 5) and ask for proof of 91.319 compliance after the testing is complete.

This is somewhat conjecture, of course, but it's my interpretation of the words in 8130.2J. I'm extremely confident in my position with respect to E-AB aircraft; marginally less so with respect to E-Exhib. aircraft. Certainly open to being proven wrong, as always.
 

BBerson

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This is somewhat conjecture, of course, but it's my interpretation of the words in 8130.2J. I'm extremely confident in my position with respect to E-AB aircraft; marginally less so with respect to E-Exhib. aircraft. Certainly open to being proven wrong, as always.
This is interesting. I may be able to convert to E-Exhib without any inspection and then later do any major changes without any approval or inspection from the FAA or DAR. Post # 4 said the FAA can require a DAR signoff at initial certification. (but maybe not)
I would be interested in what others have experienced.
Thanks.
 

TFF

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One, most FSDOs does not have the manpower to inspect planes. They have the option though if they are required to respond.

A friend with a homebuilt he bought was found to have a paperwork anomaly from a DAR from another part of the country. The plane as a project had crossed boarders a couple of times, and was re registered as its former US self. That seems to be the no no as it was given up to cross into another country. The local FSDO figures out there is some odd stuff in the FAA database that does not match what the DAR was allowed to do. For a regular major change letter, different engine prop, and new test area because the plane had been trucked in, the FAA came out twice to eyeball it. Of course they send lowest non GA inspector out. To the credit of the FAA, they saved the airplane. All the no paperwork completed airframe horrors were in play. Someone did sign the paperwork to make the plane legal again, but, but they made it fly 40 hours off like it was a new build.

Most FSDOs would tell you to scrap it. Someone is pissed about that one. Someone will be pissed that they had to fly 40 hours. Someone will be pissed that they were allowed to fly 40 hours off. It all comes down to getting the piece of paper signed. That is all. Every once in a while a washer thickness of common sense will come out of the FAA but you can’t bet on it.

Inspection of my friends plane was really more to see it existed as a physical airplane. That it wasn’t a pile of junk posing as a plane. They walked in, said “ Yep it’s yellow and black and the engine is bolted on”. Most of the visit was about trying to figure out what to do with the paperwork.

I suspect the original DAR was a friend of the seller and did not know the plane had left the country. The plane could have flown illegally forever if the original displacement engine was available.
 

proppastie

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In your letter to the local be sure to quote the appropriate rule.....especially the part about a response (in writing ) is required.
 

Pops

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My IA once called the Philly Fisdo (reportedly the worst in the nation) to ask a question, and the response was "you are an IA....figure it out yourself" ....Try to get the answer in writing ....good luck with that.
FAA friend of mine told me that the FSDO office in WV was the bottom of the barrel. Hard to believe there is another that is worse.
 
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