71-21-03 SIKORSKY: Amdt. 39-1303. Applies to all S-61 Type Helicopters certified in all categories.
Compliance required as indicated.
To prevent a hardover in the auxiliary servo system, as the result of fracture of the servo valve input linkage, accomplish the following:
a. Within the next 50 hours' time in service after the effective date of this AD, unless already accomplished, install a secondary link in the servo valve input linkage in accordance with Section 2, paragraphs A., B., C., and G., of Sikorsky Service Bulletin No. 61B65-6A, dated 1 July 1971, or later approved revisions or an equivalent installation, both approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region.
b. Install secondary links per paragraph (a) on all spare units, prior to installation on the aircraft.
This amendment is effective October 7, 1971.