Action
Notice of proposed rulemaking (NPRM).
Summary
The FAA proposes to supersede Airworthiness Directive (AD) 2020-02-17, which applies to certain Sikorsky Aircraft Corporation (Sikorsky) Model S-70, S-70A, S-70C, S-70C(M), and S-70C(M1) helicopters. AD 2020-02-17 requires recurring visual and tap inspections of the tail rotor blade (TRB) and, depending on the results, replacing the TRB. Since the FAA issued AD 2020-02-17, it was determined additional helicopter models are affected by the unsafe condition. The manufacturer has developed a split pitch horn modification and a safety enhancement modification kit for the TRB. This proposed AD would continue to require the actions of AD 2020-02- 17, would expand the applicability, and would require modifying and re- identifying the TRB. This proposed AD would also require revising the airworthiness limitations section (ALS) of the existing helicopter maintenance manual or instructions for continued airworthiness and the existing approved maintenance or inspection program, as applicable, to incorporate recurring inspections of the TRB disbond indicator. The FAA is proposing this AD to address the unsafe condition on these products.