We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD requires inspecting the main gearbox (MGB) for a crack. This AD is prompted by a crack in the cored passage of the MGB housing, which may be indicated by oil on the housing. These actions are intended to detect a crack in the MGB housing, which could result in loss of oil, failure of the MGB, and subsequent loss of control of the helicopter.
Agency Contact: Michael Schwetz, Aviation Safety Engineer, Boston Aircraft Certification Office, Engine & Propeller Directorate, FAA, 12 New England Executive Park, Burlington, MA 01803; telephone (718) 238-7761; email email@example.com.
This rule is final. Its effective date is August 1, 2012.