65-08-02 SIKORSKY: Amdt. 39-54 Part 39 Federal Register April 9, 1965. Applies to Models S-55, S-62, and S-61 Series Helicopters.
Compliance required as indicated.
Pitting in main rotor blade spars has resulted in fatigue cracks. To detect possible pitting and cracking, accomplish the following:
(a) Within 10 hours' time in service after the effective date of this AD and at intervals thereafter within 10 hours' time in service from the last inspection, until (b) has been accomplished, conduct a visual inspection for cracks of the spars of S14-10-2100 Series main rotor blades, Serial Numbers 55MH15340 through 55MH19858, in accordance with the inspection procedures specified in Sikorsky Service Bulletin 55B10-4 or 62B10-3. Replace all main rotor blades found with cracks in the spar before further flight.
(b) Unless already accomplished, within 25 hours' time in service after the effective date of this AD accomplish the following:
(1) On S-55 and S-62 helicopters, conduct an X-ray inspection of the spar of S14-10-2100 Series and S14-10-2201 Series main rotor blades, Serial Numbers 55MH15340 through 55MH19858, for pitting in accordance with the inspection procedures specified in Sikorsky Service Bulletin 55B10-4 or 62B10-3.
(2) On S-61 helicopters, conduct an X-ray inspection of the spar of S6115- 20501 Series main rotor blades, Serial Numbers 61M101 through 61M1429, for pitting in accordance with the inspection procedures specified in Sikorsky Service Bulletin 61B15-3.
(3) Replace all blades with pitting in the spar, before further flight.
This directive effective April 9, 1965.