63-05-02 SIKORSKY: Amdt. 542 Part 507 Federal Register March 6, 1963. Applies to All S-55 Series Helicopters.
Compliance required as indicated.
There has been a fatigue fracture of the main rotor blade spar. For this reason, accomplish the following:
(a) All S14-10-2000 Series main rotor blades with 975 or more hours' time in service as of the effective date of this AD shall be retired from service within the next 25 hours' time in service.
(b) All S14-10-2000 Series main rotor blades with less than 975 hours' time in service as of the effective date of this AD shall be retired from service prior to the accumulation of 1,000 hours' time in service.
This directive effective March 6, 1963.