# AD 48-17-03: Planet Pinion Shafts Wear

- Type: Airworthiness directive
- Status: Current
- Products: Sikorsky S-51
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/7736DDB28EBD288186256A55006B5AB6.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/48-17-03

## 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 data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS H-2](https://openairdocs.org/tcds/H-2): Sikorsky Aircraft Corporation; names 1 of 1 models: S-51

## Registered aircraft it may apply to (OpenAirDocs)

No registered aircraft matched the models it names.

Its text cites no advisory circulars or STCs.

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