56-05-01: Tail Rotor Drive Shafts
FAA order 56-05-01 is an airworthiness directive. The FAA's subject line: Tail Rotor Drive Shafts. It names Bell 47: about 478 aircraft on the U.S. register today, though an order usually covers particular versions or serial numbers rather than every one. System: rotorcraft systems.
What it applies to as the FAA lists it
- Kind of product
- Aircraft
- Makes
- Scotts-Bell 47 Inc
- Models
- 47, 47B, 47B3, 47D, 47D1, 47E, 47G, 47G-2, 47G-2A, 47G-2A-1, 47G-3, 47G-3B, 47G-3B-1, 47G-3B-2, 47G-3B-2A, 47G-4, 47G-4A, 47G-5, 47G-5A, 47H-1, 47J, 47J-2, 47J-2A, 47K
- On this site
- Bell 47 478 registered
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 (786 characters)
56-05-01 BELL: Applies to Model 47 Helicopters: Model 47D1 Serial Number 477 and Subsequent, Model 47G Serial Numbers 667 Through 692, 694 Through 1511, Model 47G2 Serial Numbers 1342 Through 1418, Model 47H1 Serial Numbers 1347, 1349 Through 1356, 1358, and 1360, All Model 47 Modified to Include 47-644-172-3 Tail Rotor Extension Drive Shaft and All 47-644-172-3 Shafts in Stock.
Compliance required by March 1, 1956.
As a result of manufacturing error some Bell Model 47 tail rotor extension drive shafts P/N 47-644-172-3 were bored too deep resulting in a weakened wall section. Bell has issued Service Bulletin No. 106 requiring an immediate mandatory inspection by X-ray or by method described in the Service Bulletin.
This supersedes telegraph AD of February 3, 1956.
Related safety bulletins advice on the same designs, not orders
2001-02-09SW-01-13 ·
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/56-05-01.json · aircraft systems.