Alternators

摘要

The alternator suffered a total mechanical failure after only 144.7 hours. Its replacement failed after only 41.8 hours. Observation suggests that the alternator case hardware was not properly torqued and/or did not employ a locking fluid. In both failures, the aircraft was in marginal VFR conditions. During descent, aircraft lost electric power. Pilot selected standby alternator but was unable to extend gear electrically. Manual extension was successful and the aircraft landed uneventfully. Repair station replaced the stator and rectifier.