Keeping in mind than an _ultralight_ glider is restricted to less than
155lbs,
with no other restrictions:

What regulatory differences, if any, would a homebuilder encounter
when building a sailplane or motorglider in stead of an experimental
airplane?

Does the 51% rule still apply? ( I would guess so.) Would one be
able to get an airworthiness cert for a prototype or one-off design,
as one would for an airplane?


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FF