60-04-07 WRIGHT: Amdt. 106 Part 507 Federal Register February 20, 1960. Applies to All 977C9HD1, 2 and 3 Engine Models Installed in Helicopters.
Compliance required at first engine overhaul after March 15, 1960, but not later than October 31, 1960.
To alleviate failures of the master rod assemblies, strengthened master and articulating rods with associated parts must be installed in accordance with the instructions contained in Wright Aeronautical Division Service Bulletin No. C9-353.