On Thu, 10 Jul 2008 08:07:24 -0400, "Peter Dohm"
wrote:

"150flivver" wrote in message
...

In addition, what happens if I buy a VFR plane and then replace the
engine and avionics and make it a IFR platform? Am I the builder for
the parts I put on it or does the fact that I bought an already
airworthy plane make it in essence little different than buying a 172?


Bryan Martin
N61BM, CH 601 XL, Ram Subaru, Stratus redrive.

There is only one builder and that is established when the
Airworthiness
Certificate gets issued.

that is the answer to the guys question

snip


that had to be flown off initially. Minor mods do not need anyone to
sign off on as there is no "return to service" signature needed as in
normal category aircraft. This is a primary advantage of the Amateur
Built Experimental--no STCs, no 337s, no return to service--much
different than the rules pertaining to a 172,

Actually, it can be both a primary advantage and a primary dissadvantage.
It is hypothetically possible modify the aircraft such that a new flight
test period will be required, determine during the test period that the
modification is inferior to the original, and then find that you can not
simply return to the original equipment or configuration--possibly due to
something that reportedly occurred on another aircraft. I have no idea
whether such a thing has ever occurred in practice; but it was told to me as
an illustration of one of the differences between a type certificate and a
one time approval of operating limitations.


I doubt that that is entirely correct.
what they are mixing up is the regimen of the certified aircraft and
the total absense of the regimen for amateur built experimentals.

an amateur built experimental can be modified ad infinitum since ad's
and such never apply to experimental. they are part of the certified
environment.

mods from the original signoff can invalidate the original C of A and
require it to be reissued, sending the owner through the proof of
structural integrity period again.

in the worst case where no one will issue new paperwork the owner
could surrender the registration then assemble a new aircraft from
various parts and ask for it to be registered.
if he can prove 51% then he is the builder for the new registration.

NEVER mix aspects of certification with aspects of experimental.
experimental is basically an exemption from the certification
requirements. all experimental aircraft are maintained on an
individual basis. a mishap with another similar aircraft only matters
in the certified world. experimentals are not certified aircraft.
Stealth Pilot