"Bob" wrote in message om...
What happens if you finish up a project that has been built by several
people, none of whom built 51% (and you didn't either)?

Not required to. The 51% requirement is the test to see if the airplane
was constructed primarily for "recreation and/or education." There's no
requirement that any one builder build a preponderance of the project.
It's just to say that some "amateur builder(s)" did it as opposed to an
ersatz manufacuterer cheating on the certification rules.

Obviously
you aren't the owner/builder (and can sign off the annuals) and will
have to have an A&P sign off the annuals but who is listed as the
builder?

There's no requirement that you had to build all (or most) of the aircraft
to get the repairman's certificate either. All you need to be is the
"principal builder." I've never heard of the FAA not allowing the
last builder (i.e. the guy who gets it signed off) to not count as the
principal builder.