When does an experimental become a new plane?

[thisadviceisworthles]

I noticed another post about buying a deregistered experimental, and it leads to me wondering when a plane is a new plane.

If, hypothetically, that deregistered plan was purchased for parts to build a new one, how much could be used as parts and still certificate as a new E-AB?

[Sam Buchanan]

As stated in the other thread, the main hurdle to jump is establishing at least 51% of the aircraft being amateur-built. If so the aircraft could be reassembled and presented for an experimental airworthiness inspection. The aircraft becomes a "new" aircraft when the airworthiness certificate is issued.

[DaleB]

I wonder if the previous E-AB airworthiness certification would be sufficient to prove majority amateur construction. I mean, presumably it was proven to be amateur built at some point... its component parts are not going to get any LESS amateur built.

[Frank Giger]

Dale, that's a bad road to go down, as one is the nebulous business of saying that the parts amateur built are part of the theoretical 51% and not the 49% that isn't.

The Builder's Log, however, is absolute gold for this purpose, as it shows fabrication of each part used.

When a plane is decertified, it's just parts, and becomes just that. Showing that the parts were fabricated is the big deal here.

In fact, I wouldn't muddy the waters with a prior pink slip too much.

[DaleB]

Totally agree that IF the builder's log exists, or other docs, they could and should be used if they exist. My question was whether, if one were trying to resurrect a de-certified E/AB without adding any non amateur built parts, the fact that it was originally certified as E/AB would count for anything. Mathematically, if I start with something that was 51% amateur built, and I do repairs or build new parts that are amateur built, then it can't get any LESS amateur built. Right?

Of course it may just be a lawn ornament. That sort of thing happens.

[1600vw]

The FAA in OKC explained it this way to me. Once an airplane is deregistered, the old Airworthy Certificate is no longer valid. You can not use it to prove anything. That paper has been destroyed. So now if you want to try and get this airplane flying you must have it reinspected as a complete airplane. Seeing how you can not prove who built it or anything else, it will have some special registeration. It was explained to me, if you ever want to fly the airplane again, don't destroy the orginal registration. Once this paper work is filled, your airplane is now screwed. It was also explained to me if someone does this, declares and airplane destroyed and in fact it is not. Someone is in deep. There are laws against filling false papers with the federal government.

Tony