There's a lot of competition to be the worst FSDO.
So there's lots of variation.

Standing is the key. If you don't have it, you will
have a very hard time.

That AC does make it sound like a minor alteration.
But it doesn't say anything about the approved flight
manual. It is written for people of standing. Still a 337
required around here.

Remembering Rule #1 will help: "It doesn't have to
make sense!"

I once got a one shot STC for a homebuilt 3 axis
autopilot. I'd hate to imagine what that would take
now. It was hard 20 years ago.

Bill Hale Denver area

Newps wrote:
In the last couple years the FAA has determined that GPS installs are
minor alterations. Perhaps your FSDO didn't get the memo.



Denny wrote:
My FSDO is requiring that 'they' inspect and sign off every IFR GPS
install, especially the antenna, before it is legal to fly the
airplane... i.e. once the antenna is hung the airframe is no longer
airworthy until FSDO approved... Backyard mechanics need not apply as
the inspector is requiring a sign off by a 'licensed radio shop' before
he will make the drive to look at the ship... I don't know if this is
from OK City, or just a wild hair up this FSDO... I became aware of
this when I picked up a ship that had a new install... It was parked on
the ramp at the radio shop and the owner asked me to retrieve it while
he was out of town... The line boys know me and knew I was taking it
.. Anyway, the owner got a panic call from the radio shop that his ship
was not legal to fly as the FSDO had not signed off yet, so I had to
quietly fly it back that night and let it sit another week before the
FSDO came around...

For the nit pickers, don't bother hyperventilating - yes it was also
not legal to fly back, but a phone conference with all involved decided
this was the best way to handle it...

denny