...If they did, everyone would be able to perform annuals or modifications on their 150/152's
That's my point! Anyone CAN perform ANY maintenance on their 150's or 152's... under properly certified supervision, which often can be as little as an inspection after the fact! I agree that you won't be allowed to do everything without some over-the-shoulder coaching, and the A&P still does the signoff!
You still need A&P supervision on a homebuilt! The FAA designated examiner who periodically inspects your work during the build is also an A&P/IA, and you will require his signoff before first flight. Afterwards, while you might perform any maintenance on your homebuilt and signoff any logs yourself, you'll still need a repairman's certificate good only for your plane, requiring documentation acceptable to the FAA that you built 51% of the plane. If you built less than 51% (after buying someone's partially completed project, for instance), you don't get the repairman's certificate, and an A&P still has to do all the signoffs. I also believe the annual re-certification inspection still needs an A&P signoff, regardless (somebody correct me if I'm wrong here). I believe there are also certain operational restrictions with homebuilts that aircraft built under a production authorization don't have, such as airspace where they CAN'T be flown (again, I may be wrong).
Nobody clearly understands the FAA (even the FAA) but there is reasoning behind most of the madness!
