47-50-08: Vertical Hinge Pins
FAA order 47-50-08 is an airworthiness directive. The FAA's subject line: Vertical Hinge Pins. System: other and general.
What it applies to as the FAA lists it
- Kind of product
- Aircraft
- Makes
- Sikorsky Aircraft Corporation
- Models
- S-51
Dates and paperwork
- Docket
- Unknown
- Status
- Current
- The FAA's document
- Read the order on the FAA's site
The order itself the regulatory text, as published
Show the full text (1,114 characters)
47-50-08 SIKORSKY: Applies to Model S-51 Helicopters.
Compliance required at each 200-hour inspection period.
Disassembly and inspection of the vertical hinge pins and bearings is a mandatory procedure and should be accomplished at each 200-hour inspection period.
The helicopters which utilize Torrington No. 4479 bearings at the vertical hinge pins are subject to replacement of these bearings at each 200-hour inspection period.
The procedure followed is explained on page 4 of Sikorsky Service Bulletin No. 7 dated August 4, 1947.
Helicopters which utilize Smith 14TR-X1 bearings at the vertical hinge pins are subject to inspection at each 200-hour interval and replacement of the bearings is not required unless the installation shows sign of serious wear or damage.
Helicopters which utilize Torrington No. 4479 bearings at the vertical hinge pins can be reworked to incorporate Smith 14TR-X1 bearings at the vertical hinge pins if desired by the owner.
(The procedure to follow for this exchange of bearings is as explained on page 2 of Sikorsky Service Bulletin No. 7 dated August 4, 1947.)
Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 6, 2026. Connections as data: /graph/directive/47-50-08.json · aircraft systems.