• FAA

Piper Safety concern Bulletin for Alternator out light/switch

The FAA was made aware of model PA28-161 Cadet in the Netherlands had a “Low Volt” light illuminated and quite a lot of white smoke appeared from below the left hand side of the instrument panel, while in flight. This resulted in the crew of the aircraft declaring an emergency, performing the Electrical Fire emergency checklist actions, followed by the Forced Landing emergency checklist actions, and then landed with no injuries. The pilot in command shut the engine down, and the occupants evacuated the aircraft. The investigation found that a fuse in the circuit would have prevented the event. The investigation also revealed that Piper Aircraft Company issued a Service Bulletin SB 991A, dated 1/10/1996, addressing possible smoke formation from a failed alternator out switch. The service Bulletin provided instructions for the installation of a fuse on the alternator aux terminal. The subject aircraft did not comply with Service Bulletin 991A.


The FAA has been made aware of a model PA28-161 Cadet in the Netherlands that had a “Low Volt” light illuminate, and then white smoke appeared from below the left-hand side of the instrument panel while in flight. This resulted in the aircrew declaring an emergency, performing the electrical fire emergency checklist actions, followed by the forced landing emergency checklist actions, and then landing with no injuries. The pilot in command shut the engine down, and the occupants evacuated the aircraft. An investigation found that a fuse in the alternator aux circuit would have prevented the event. The Piper Aircraft Company issued a Service Bulletin, SB 991A, dated 1/10/1996, addressing possible smoke formation from a failed alternator-out switch. The service Bulletin provided instructions for installing a fuse on the alternator auxiliary terminal. The subject aircraft did not have the modification to comply with Service Bulletin 991A.


The FAA is concerned that other aircraft included within the affected by of SB991A may not have accomplished the modification. The FAA would like to gather data to determine if this issue requires additional consideration in light of the reported incident/accident.

This is a link to the Airworthiness Concern Sheet that contains the model and serial numbers affected by the issue.


https://www.faasafety.gov/files/notices/2021/Dec/ACS_Piper2021correct_Final.pdf

This is a link to Piper Service Bulletin 991A, Replacement or Modification of the Alternator Out


Light Circuit Fuse. https://www.faasafety.gov/files/notices/2021/Dec/SB_0991A.pdf

The FAASTeam provides a Fact Sheet for Service Bulletin compliance by following this link: Service Bulletins and the Aircraft Owner (faa.gov)


For questions, please contact: Bryan Long, Aerospace Engineer Atlanta ACO Branch Bryan.Long@faa.gov 404-474-5578

1 view

Recent Posts

See All

AIRCRAFT OWNERS – I Did It and You Should Too! Notice Number: NOTC2262 If you own an aircraft and have been asked to participate in the 2021 FAA’s General Aviation Survey, disseminated through Tetra T

Part 91 operators would soon have a streamlined access to obtaining Letters of Authorization (LOAs) as the result of recommendations of a working group of FAA and industry representatives as it has be