70-17-03 HUGHES: Amdt. 39-1070. Applies to Model 269 Series helicopters certificated in all categories, which incorporate lead-lag and flapping hinge bolts, P/N HS 1446- 10-68, (only the lead-lag bolts are affected on Model 269C) with vendor identification BM (stylized) impression stamped on top of the bolt heads hereinafter referred to a BM bolts.
Compliance required as indicated.
To detect cracks in the BM bolts, P/N HS 1446-10-68, accomplish the following:
Within 50 hours time in service after the effective date of this AD, unless already accomplished, remove all BM bolts in accordance with Hughes Handbook of Maintenance Instruction (BM bolts with the head dyed green or a white dot painted in the recessed head have been inspected and are not affected by this AD. The white dot was used in instances where the green dye application was not effective.) Perform a magnaflux inspection of the BM bolts for evidence of cracking.
(a) Replace any BM bolt which shows evidence of cracking, with a serviceable bolt prior to further flight. Efface the part number of any cracked bolts sufficiently to prevent their inadvertent return to service.
(b) Any BM bolt which shows no evidence of cracking may be returned to service after it has been identified with a white dot painted in the recessed head of the bolt.
NOTE: (Hughes Service Information Notice No. N-78, dated July 31, 1970, pertains to the same subject.)
This amendment becomes effective August 20, 1970.