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Action

Notice of proposed rulemaking (NPRM).

Summary

The FAA proposes to adopt a new airworthiness directive (AD) for Siam Hiller Holdings, Inc. (Siam Hiller), Model UH-12E (Army OH-23G and H-23F) and UH-12E-L helicopters. This proposed AD was prompted by reports of cracks found in a main rotor (M/R) transmission drive shaft (drive shaft). This proposed AD would require inspecting certain M/R drive shafts for a crack, prohibit installing certain M/R drive shafts unless the inspection is done, and prohibit using certain paint removers. The FAA is proposing this AD to address the unsafe condition on these products.

Document

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