airworthiness · Rule · Final rule; request for comments. · Published 2012-01-06 · Effective 2012-01-23 · 77 FR 729
Document
Document number
2011-32895
Federal Register citation
77 FR 729
Type
Rule
Action
Final rule; request for comments.
Category
airworthiness
Manufacturer
Enstrom Helicopter Corporation
Publication date
2012-01-06
Effective date
2012-01-23
FAA docket
Docket No. FAA-2011-1382
Abstract
We are adopting a new airworthiness directive (AD) for Enstrom Helicopter Corporation (Enstrom) Model F-28C, F-28C-2, F-28F, 280C, 280F, 280FX TH-28, 480, and 480B helicopters with certain trim relays to require modifying and testing the lateral and longitudinal cyclic trim actuator assemblies. This AD was prompted by four failures in the cyclic trim system on certain Enstrom model helicopters that resulted in reduced controllability of the helicopter. These actions are intended to prevent failure of the cyclic trim system and subsequent loss of control of the helicopter.