The FAA Safety Team posted a notice December 8 detailing the issue, and including links to an airworthiness concern sheet (ACS) published in October following the incident in the Netherlands. The pilot of a Piper PA–28-161 Cadet (a variant of the Piper Cherokee) noticed white smoke coming from below the instrument panel after a “low volt” light illuminated, declared an emergency, worked the electrical fire emergency checklist, and made a forced landing with no injuries to the pilot or passengers. An investigation revealed that a modification (installation of a fuse in that circuit) called for in a Piper Aircraft Co. service bulletin issued in January 1996, and applicable to several Piper models, had not been performed.
The ACS notes that the service bulletin in question applies to several Piper single- and twin-engine aircraft, including the Cadet; Aztec; Arrow, Arrow III, and Turbo Arrow III; Navajo; Chieftain; Pressurized Navajo; and Tomahawk. In each case, only aircraft with serial numbers within a certain range required corrective action.
The FAA is gathering information from aircraft owners and operators to assess whether further action is required by issuing an ACS to collect the data.
“This Airworthiness Concern Sheet (ACS) is intended as a means for FAA Aviation Safety Engineers to coordinate airworthiness concerns with aircraft owners/operators through associations and type clubs,” the agency stated in the ACS. “At this time, the FAA has not made a determination on what type of corrective action (if any) should be taken. The resolution of this airworthiness concern could involve Airworthiness Directive (AD) action or a Special Airworthiness Information Bulletin (SAIB), or the FAA could determine that no action is needed at this time. The FAA’s final determination will depend in part on the information received in response to this ACS.”
Owners and operators of aircraft subject to Piper Service Bulletin 991A are asked to contact FAA Aerospace Engineer Bryan Long via email, or by calling 404-474-5578, or by mail to 1701 Columbia Ave., Atlanta, Georgia, 30337, and confirm that the modification (fuse installation) called for in the service bulletin has been completed. If that work was not done, or if it cannot be confirmed, the FAA would like to know if the aircraft has “an alternate method to ensure that if the alternator out light solid state switch fails, there is still a safety barrier in the aircraft or if [that] cannot be determined please simply respond with ‘No’ or ‘Unknown’? If there is an alternate method[,] please provide [the details] of the installation.”
AOPA Senior Director of Regulatory Affairs Christopher Cooper said that the ACS process is a valuable tool to enhance safety and avoid unnecessary directives, and he is working with the FAA on efforts to raise awareness about the process among general aviation pilots. Cooper encouraged owners of Piper Aircraft listed in the ACS to respond promptly.