54-19-02 SIKORSKY: Applies to All Model S-55 Helicopters.
Compliance required before October 1, 1954.
To insure against the loosening of the servo pilot valve locknut and subsequent improper servo operation, safety clips, Sikorsky P/N S-14-40-5194, should be installed and safetied to P/N S14-40-3227-24 lockwasher.
(Sikorsky Service Information Circular 1440-458 covers this same subject.)