SAIB - Pipers Cherokee & Seminole

On October 24, 2010, the FAA issued a Special Airworthiness Inspection Bulletin (SAIB) for Piper Cherokees and
Seminoles.

The bulletin discusses a potential issue with stress corrosion cracking at the turnbuckle/control cable assembly leading to
the stabilator which can cause the loss of pitch control.

Two incidents occurred in 2008 which prompted the FAA to issue the SAIB. One of the incidents involved a Seminole
on its takeoff roll. The pilot noticed a problem with the horizontal stabilator and aborted the takeoff. The other incident
involved a Cherokee while it was in flight. The pilot landed safely using stabilator trim and engine power and while the
landing was hard, there was no damage to the plane or, apparently, the pilot. Both incidents were caused by failure of the
control cables and/or turnbuckles leading to the stabilator.

Back in 2003, Piper recognized the potential problem and issued a service letter that discussed it. The service letter
described a specific inspection be carried out for planes that have been in service for more than 15 years. It also
mandated that a logbook entry be made specifically about the cable/turnbuckle inspection.

The incidents which happened in 2008 seem to indicate that the control cable/turnbuckle inspection procedure may have
fallen off some people's radar. Thus, we recommend you do the following three things:

1. Review your airframe logbook to see if any entries were made in the past which indicate compliance with the control
cable/turnbuckle inspection procedure from 2003;

2. Before your next annual inspection, when you discuss the inspection with the personnel at your shop, specifically
remind them about the service letter;

3. Once the annual inspection is complete, review the logbook entry to ensure compliance with the control
cable/turnbuckle inspection procedure.

On January 5, 2011, the FAA issued several Special Airworthy Information Bulletins (SAIB) for the PA-28, -32, -34, and
-44 series Pipers regarding the possibility of corrosion involving the vertical stabilizer, the wing front spar, the wing rear
spar, the aileron hinge fitting, and areas around the flaps. (If you click any of the links, you'll get to the documents in pdf
format.)

The FAA issues SAIBs when they hear about a safety problem with an airplane but the problem’s not endemic to the entire
fleet. If they believe the problem poses an unsafe condition, they issue an AD.

Over the years, Piper has issued a variety of Service Bulletins (SB) that discuss the possibility of corrosion in areas relating
to the control surfaces. The bulletins recommend procedures for inspecting those different areas. Some of the inspections
are quite involved and require getting under the riveted skin of the plane to peek inside.

The service bulletins issued by aircraft manufacturers aren’t mandatory and neither are SAIBs. Nevertheless, you should
keep them in mind whenever you do your preflight inspection and again when it's time for the annual inspection. While one
or more of the SBs call for peeking under the skin, corrosion tends to migrate and it shows through paint, too. We suggest
that you read the SAIBs, learn where they call attention to corrosion problems, then carefully look at the external skin in
those areas on your plane to see if there are any abnormalities.

If your plane lives in - or came from - a wet or coastal environment, and particularly if it has no corrosion proofing, we
strongly recommend that in spite of the expense of complying with the SBs, you direct your mechanic to perform the
recommended inspections and detail them in the airframe log book.