- Model
- S-51
- Data sheet
- TCDSH-2
- Product
- Aircraft · Rotorcraft
Unofficial copy of the text in the FAA’s Dynamic Regulatory System. The FAA’s own copy is the authoritative one. DRS record last changed May 30, 2024.
Copies of the files this page was built from, with their SHA-256. Retrieved October 18, 2026.
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|---|---|---|---|
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The airworthiness directive
48-17-03 SIKORSKY: Applies to Model S-51 Helicopters.
Compliance required at each 800-hour inspection.
In order to preclude any malfunctioning of the main rotor gearbox due to the normal wear which may be expected to occur in the primary and secondary planet pinion shafts (Sikorsky P/N S-535524), these parts should be rotated 180 degrees or replaced by new parts after 800 hours of operation. If rotated, replacement by new parts should be made after an additional 800 hours.
(Sikorsky Aircraft Service Information Circular No. 8 Revision "B" dated January 13, 1948, covers this same subject.)
AD 48-17-03
Affected TCDS · 1
The type certificate data sheets for the models this AD names, matched by model and maker.