What is involved regulation wise adding an electric motor to a glider?

On Tuesday, February 2, 2021 at 5:10:00 PM UTC-8, David Scott wrote:
On Tuesday, February 2, 2021 at 1:26:10 PM UTC-8, David Scott wrote:
I DON'T mean to stir up trouble on this forum with this question, especially being new, but have been wondering about this for some time. I am wondering how feasible it would be to do this with either a homebuilt or experimental glider here in the US?

I figure this has been asked but didn't find any threads on it.
Thank you for your responses. To be clear I don't have a sailplane but would like to get into the sport and the answers to this question would possibly affect what glider I would get. I am smart enough to get all my ducks in a row before doing anything, and this is the first I have talked about it.. From an engineering standpoint, it doesn't look too difficult, navigating the regulations is where I expect the most trouble.

This would be cost prohibitive to certify; possibly hundred$ of thousands and years of your life. However, there are several ways to accomplish this with experimentals. As you mentioned, you could modify a homebuilt sailplane with an Amateur Built experimental airworthiness certificate. Alternatively, you could put a factory-built sailplane into an experimental category for R&D or Racing and Exhibition.

As somebody mentioned, each experimental airworthiness certificate is issued with a list of operating limitations. Almost always, the operating limitations require you to notify the FAA of any major alterations. The FAA would most likely require an airworthiness inspection, just to make sure you didn't do anything silly. They would also require a flight test period. Usually, this is 40 hours for an amateur built experimental with an uncertified engine/prop.

I've brought numerous aircraft into experimental categories and modified the hell out of them. In every case, the FAA was super easy to work with. I'd recommend that you make an appointment to discuss this with your local FSDO.