56-23-03 SIKORSKY: Applies to All Model S-55 Helicopters.
Compliance required as indicated.
Due to additional failures, it has been found necessary to lower the retirement time specified in AD 56-10-02. Accordingly, the horizontal hinge pin assembly, P/N S10-10-3331 and S10-10-3331-1 with 750 hours service must be replaced by December 1, 1956, or prior to the accumulation of 850 hours, whichever occurs first. Parts with 850 hours or more must be replaced prior to further service. Thereafter, P/N S10-10-3331 and S10-10-3331-1 are to be retired at not more than 750 hours.
This supersedes AD 56-10-02.