Our 1979 Arrow IV is in the shop for its annual inspection. As usual, the
inspection itself went smoothly, but it uncovered some maintenance items
that will run into several AMUs. Here are the top three uglies:

1) The inspection part of Piper Service Bulletin 1161 resulted in
identification of cracks in both affected wing ribs. That's the bad news.
The good news is that the cracks are in locations that will allow the use of
the Piper repair kits, which Piper stocks. Jack Allison has posted on this
NG his horror story of replacing the ribs when the cracks precluded use of
the repair kits, so in a way we feel lucky. Cost estimate for the SB
compliance with the repair kits is about 1.3 AMU, including parts and the
initial inspection.

2) The hydraulic power pack has to be replaced or overhauled. We can't feel
too bad about this one because it's the original (1979) unit. 27 years is a
more than reasonable service life. A rebuilt replacement goes for 0.8 AMU,
which is about the cost of overhauling ours. We will do a swap in order to
avoid downtime for an overhaul.

3) The biggie! The support structure under the wing walk is cracked in
several places and needs to be replaced. This is apparent from a slight
"oilcanning" of the wing skin in the wing walk area when we step on it.
Repair will necessitate removing the right wing, a bunch of drilling to
remove the old structure, replacing it with a new assembly (cost unknown)
and replacing the wing. our mech estimates (roughly) the job will take
about 24 hrs of labor and cost, with parts, around 2 AMUs. It's not really
a safety issue as the structure only supports and reinforces the wing walk
-- it is not part of the primary wing structure. But left unrepaired the
outer skin could crack, resulting in a much bigger repair job. Our shop has
never done this job before but one of the assistant A&Ps has, and the
estimate is largely based upon his knowledge. Have any of you other
PA-28/PA-32 owners had this problem?

The rest of the identified maintenance items are the usual collection of
individually minor items -- a seal here, a gasket there -- but of course
collectively they typically add up to about 1 AMU.

Glad this is going to be split 3 ways!


-Elliott Drucker