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Action

Final rule.

Summary

We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD was prompted by the discovery of tail rotor blade assemblies (blades) manufactured with mislocated aluminum wire mesh, leaving portions of the graphite torque tube (spar) region unprotected from a lightning strike. The actions are intended to detect mislocated blade wire mesh and to prevent spar delamination, loss of the blade tip cap during a lightning strike, blade imbalance, loss of a blade, and subsequent loss of control of the helicopter.

Document

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