The AD requires inspections of the stabilator control system and replacement of parts as necessary. We are issuing this AD to correct the unsafe condition on these products. In the discussion posted on the Federal Register Monday, the FAA said that according to NTSB Chair Deborah Hersman, two special airworthiness information bulletins (SAIBs) have been issued that recommend inspecting the entire surface of each cable terminal, turnbuckle, or other cable fittings for corrosion or cracking. Within the past 2 years, the NTSB has investigated two accidents and one incident involving Piper airplanes where control cable assembly failures due to stress corrosion cracking led to failures of the horizontal stabilator control system. She stated that the fact these events continue to occur more than 10 years after the SAIBs were issued shows that the SAIBs were not effective. The NTSB supports the need for this AD.
Piper investigated the possibility of using a commercial product called “scotch-brite” to remove surface corrosion and found it to be acceptable. The FAA said it will change this AD to reference the revised Piper Aircraft, Inc. Mandatory Service Bulletin No. 1245A, dated November 28, 2012, which incorporated cleaning agents and scotch-brite.
The inspection is expected to cost individual owners of the airplanes about $425 according to an estimate provided by the FAA. If it is determined that the stabilator control system needs to be replaced, that repair is estimated to cost the individual owner $1,458 in parts and labor.
The AD is effective March 11.