Servo Tab on DHC-3 Otter
Summary: Design and Manufacturing of redundant servo-tab for installation on DHC-3 Otter for Airworthiness Directive (AD).
Client Request: The DHC-3 Otter had a history of failures in the elevator servo-tab bellcrank. VAZAR agreed to address this issue on their turbine conversion to increase safety of the aircraft and meet the newer 23.629 requirement of flutter free after a single failure. Volant Technica was asked to develop the fix for the servo tab.
Project Summary: Volant Technica, a precursor company to Fliegen Works, worked with the FAA to address this service difficulty and produced the design data, developed loads and a structural test proposal, then DER witnessed the structural test. We also wrote the flight test plan and helped with the issuance of the TIA. The STC is a method of compliance to AD 2004-05-01. Fliegen Works currently holds PMA for fabrication of the redundant servo tab; it includes a 2nd control rod and other modification to fix in-service failure problem.
Results: STC SA01059SE was granted to VAZAR (as American Aeromotives) and is licensed to Fliegen Works for European import auto repair under PMA PQ2380NM.