How do I legallly install winglets on a standard airworthiness certificate?

OK...I am not the original poster...at present I do not own a
sailplane...just a powered expermental airplane. *I didn't realize it
was apparently fairly easy (???) to ask the FAA to change from a
standard to experimental airworthiness certificate. *Maybe I will see if
I can get our Cessna 140 into the experimental class so I can do more owner maint/mods

Scott, you are apparently confusing Experimental Homebuilt (where the
original builder can maintain "his" plane) with Experimental Racing
and Exhibition, which is the catagory many gliders are registered in.

No way you can change your 140 to Ex-homebuilt, but you could probably
change it to EX-Racing and Exhibition.

I'll leave it to smarter people than I to explain the difference.

Kirk
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