# AD 70-08-02: Tail Rotor Drive Shaft - Type: Airworthiness directive - Status: Current - Products: Scotts-Bell 47 47, 47B, 47B3, 47D, 47D1, 47E, 47G, 47G-2, 47G-2A, 47G-2A-1, 47G-3, 47G-3B and 12 more - Effective: January 1, 1971 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Rotorcraft - Amendment: 39-1137 - Registered aircraft: 490 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/5AA68653A4C2FE7986256E01005AC4B2.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/70-08-02 ## The airworthiness directive 70-08-02 BELL: Amendment 39-968 as amended by Amendment 39-1137 Applies to all Bell Model 47 Series Helicopters and all other helicopters incorporating any of the following tail rotor drive shaft assemblies: 47-644-172-3 47-644-180-1 47-644-186-1 47-644-180-5 47-644-187-5 47-644-214-1 47-644-187-11 Compliance required no later than March 1, 1971; however, replacement is recommended at the next 1200-hour overhaul. To prevent failure from internal corrosion, remove and replace all tail rotor drive shaft assemblies installed on applicable helicopters as indicated below in accordance with the applicable maintenance and overhaul manual: Remove Replace With 47-644-172-3 47-644-172-9 47-644-180-1 47-644-180-9 47-644-180-5 47-644-180-11 47-644-214-1 47-644-214-9 47-644-186-1 47-644-186-5 47-644-187-5 47-644-187-17 47-644-187-11 47-644-187-19 (Bell Service Bulletin No. 47-145, Rev. B, dated March 26, 1970, pertains to this matter) Amendment 39-968 effective May 9, 1970. This amendment, 39-1137, becomes effective January 1, 1971. ## Affected data sheets (3) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS 2H3](https://openairdocs.org/tcds/2H3): Scott's-Bell 47 Inc; names 11 of 11 models: 47G-2A, 47G-3B, 47G-3, 47G-4A, 47G-5A, 47G-5, 47G-3B-2A, 47G-3B-2… - [TCDS H-1](https://openairdocs.org/tcds/H-1): Scott's-Bell 47 Inc; names 9 of 9 models: 47H-1, 47B, 47B3, 47D1, 47D, 47G-2, 47G, 47… - [TCDS 2H1](https://openairdocs.org/tcds/2H1): Scott's-Bell 47 Inc; names 4 of 4 models: 47K, 47J-2, 47J-2A, 47J ## Registered aircraft it may apply to (OpenAirDocs) Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment. - Aircraft: 490 (490 by airframe model, 0 by engine model) - Makers: Bell 476, Bell-K-Copter 3, Bell Kitz Kopters 1, Bell-Allied Helicopter 1, Bell-Carson 1, Bell-Huddleston And Wilson 1, Bell-Intermountain 1, Bell-Olympic Helicopters 1, Bell-Shippey 1, Bell-Tellijohn 1 Models with the most aircraft: - [Bell 47G-2](https://openairdocs.org/model/bell-47g-2): 87 aircraft (airframe model) - [Bell 47G-3B-1](https://openairdocs.org/model/bell-47g-3b-1): 86 aircraft (airframe model) - [Bell 47G](https://openairdocs.org/model/bell-47g): 55 aircraft (airframe model) - [Bell 47D1](https://openairdocs.org/model/bell-47d1): 47 aircraft (airframe model) - [Bell 47G-5](https://openairdocs.org/model/bell-47g-5): 40 aircraft (airframe model) - [Bell 47G-3B-2](https://openairdocs.org/model/bell-47g-3b-2): 26 aircraft (airframe model) - [Bell 47G-4A](https://openairdocs.org/model/bell-47g-4a): 20 aircraft (airframe model) - [Bell 47G-2A](https://openairdocs.org/model/bell-47g-2a): 19 aircraft (airframe model) - [Bell 47G-5A](https://openairdocs.org/model/bell-47g-5a): 19 aircraft (airframe model) - [Bell 47G-3B](https://openairdocs.org/model/bell-47g-3b): 15 aircraft (airframe model) - [Bell 47G-2A-1](https://openairdocs.org/model/bell-47g-2a-1): 13 aircraft (airframe model) - [Bell 47G-4](https://openairdocs.org/model/bell-47g-4): 13 aircraft (airframe model) - [Bell 47G3B2A](https://openairdocs.org/model/bell-47g3b2a): 7 aircraft (airframe model) - [Bell 47H-1](https://openairdocs.org/model/bell-47h-1): 6 aircraft (airframe model) - [Bell 47J](https://openairdocs.org/model/bell-47j): 6 aircraft (airframe model) - [Bell 47J-2](https://openairdocs.org/model/bell-47j-2): 6 aircraft (airframe model) - [Bell 47J-2A](https://openairdocs.org/model/bell-47j-2a): 5 aircraft (airframe model) - [Bell 47D](https://openairdocs.org/model/bell-47d): 4 aircraft (airframe model) - [Bell-K-Copter 47G](https://openairdocs.org/model/bell-k-copter-47g): 2 aircraft (airframe model) - [Bell 47B](https://openairdocs.org/model/bell-47b): 1 aircraft (airframe model) All 35 models: https://openairdocs.org/ad/70-08-02/models.md Every aircraft: https://openairdocs.org/ad/70-08-02/aircraft.md Its text cites no advisory circulars or STCs. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.