# AD 85-15-04: Tail Rotor Blade Yolk P/N 74-641-057-9

- Type: Airworthiness directive
- Status: Current
- Products: Scotts-Bell 47 47B, 47B3, 47D, 47D1, 47E, 47G, 47G-3, 47H-1, OH-13E and OH-13E
- Effective: January 8, 1986
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-5186
- Registered aircraft: 121 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/21FDB451D687ABB086256A4D0073C59C.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/85-15-04

## The airworthiness directive

85-15-04 BELL HELICOPTER TEXTRON, INC., HAWKEYE ROTOR AND WING, TEXAS HELICOPTER CORPORATION: Amendment 39-5186. Applies to Model 47B, 47B3, 47D, 47D1, 47E, 47G, 47H-1, 47G-3, U.S. Army Model OH-13E helicopters certified in any category and other helicopters equipped with tail rotor blade yoke P/N 74-641- 057-9.

Compliance is required as indicated, unless already accomplished.

To prevent the failure of the tail rotor blade yoke, accomplish the following:

a. Within the next 10 hours time in service after the effective date of this AD, remove from service Texas Helicopter Corporation tail rotor blade yoke P/N 74-641-057-9.

b. Any equivalent method of compliance with this AD which provides an equivalent level of safety may be used when approved by the Manager, Helicopter Certification Branch, Federal Aviation Administration, 4400 Blue Mound Road, Fort Worth, Texas 76106.

c. In accordance with FAR Sections 21.197 and 21.199, flight is permitted to a base where the replacement required by this AD may be accomplished.

This amendment becomes effective January 8, 1986, as to all persons except those to whom it was made immediately effective by priority letter AD 85-15-04, issued July 23, 1985, which contained this amendment.

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS H-1](https://openairdocs.org/tcds/H-1): Scott's-Bell 47 Inc; names 7 of 9 models: 47H-1, 47B, 47B3, 47D1, 47D, 47G, 47E
- [TCDS 2H3](https://openairdocs.org/tcds/2H3): Scott's-Bell 47 Inc; names 1 of 11 models: 47G-3

## 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: 121 (121 by airframe model, 0 by engine model)
- Makers: Bell 114, Bell-K-Copter 2, Bell Kitz Kopters 1, Bell-Allied Helicopter 1, Bell-Carson 1, Bell-Shippey 1, Continental Copters 1

Models with the most aircraft:

- [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 47H-1](https://openairdocs.org/model/bell-47h-1): 6 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)
- [Bell OH-13E](https://openairdocs.org/model/bell-oh-13e): 1 aircraft (airframe model)
- [Bell Kitz Kopters 47D1](https://openairdocs.org/model/bell-kitz-kopters-47d1): 1 aircraft (airframe model)
- [Bell-Allied Helicopter 47D1](https://openairdocs.org/model/bell-allied-helicopter-47d1): 1 aircraft (airframe model)
- [Bell-Shippey BELL 47G](https://openairdocs.org/model/bell-shippey-bell-47g): 1 aircraft (airframe model)
- [Bell-Carson 47G](https://openairdocs.org/model/bell-carson-47g): 1 aircraft (airframe model)
- [Continental Copters 47G](https://openairdocs.org/model/continental-copters-47g): 1 aircraft (airframe model)

All 12 models: https://openairdocs.org/ad/85-15-04/models.md
Every aircraft: https://openairdocs.org/ad/85-15-04/aircraft.md

Its text cites no advisory circulars or STCs.

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