FAA finalizes Piper cable inspection AD
Two NTSB investigations in the past two years have found corrosion of the stabilator cable contributed to loss of control accidents involving a Piper Cherokee Lance and Turbo Saratoga. The FAA has updated an airworthiness directive and will now require inspections of those control cables in various Piper models that are 15 years old or older as of March 1.
The NTSB supported the mandate, noting that corrosion and stress continue to cause control cable failures a decade after special airworthiness information bulletins (SAIBs) were issued on the same topic.
The new directive allows owners to complete the inspections in conjunction with the next annual inspection due after March 1, and every 2,000 hours thereafter. The FAA estimates 34,013 aircraft in the U.S. registry are subject to the requirement. The directive was also revised to allow the use of Scotch-Brite and similar products from the cable and turnbuckle in keeping with a service bulletin issued by Piper in November 2012. The final rule notes there have been “multiple reports” of cable corrosion and fraying in various models.
Corrosion, fatigue, and fraying are not just a problem for older-model Pipers--all aircraft owners should expect some degree of corrosion and fatigue as airplanes age. The AOPA Air Safety Institute offers a free online course covering a range of issues with aging aircraft.
February 6, 2013