# AD 86-12-06: Main Rotor Yoke Assemblies

- Type: Airworthiness directive
- Status: Current
- Products: Bell Helicopter Textron 214ST
- Effective: July 1, 1986
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-5329
- Registered aircraft: 19 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/9DB2D390AACF9F2986256A4E00503CDA.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/86-12-06

## The airworthiness directive

86-12-06 BELL HELICOPTER TEXTRON, INC.: Amendment 39-5329. Applies to Bell Helicopter Textron, Inc., Model 214ST helicopters, S/N's 18401, 18402, 18403, and 28101 through 28159, certificated in any category, equipped with main rotor yoke assembly P/N 214- 010-105-001.

Compliance is required as indicated, unless already accomplished.

  (a) To prevent failure of the main rotor yoke assembly, remove and replace the yoke assembly not later than 2,500 hours time in service. For yoke assemblies that have accumulated more than 2,450 hours time in service as of the effective date of this AD, remove and replace the yoke assembly within the next 50 hours time in service or by July 1, 1986, whichever comes first.

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

This amendment becomeseffective July 1, 1986.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS H10SW](https://openairdocs.org/tcds/H10SW): McDermott 214 Holdings, LLC; names 1 of 1 models: 214ST

## 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: 19 (19 by airframe model, 0 by engine model)
- Makers: Bell 18, Bell Helicopter Textron 1

Models with the most aircraft:

- [Bell 214ST](https://openairdocs.org/model/bell-214st): 18 aircraft (airframe model)
- [Bell Helicopter Textron 214ST](https://openairdocs.org/model/bell-helicopter-textron-214st): 1 aircraft (airframe model)

All 2 models: https://openairdocs.org/ad/86-12-06/models.md
Every aircraft: https://openairdocs.org/ad/86-12-06/aircraft.md

Its text cites no advisory circulars or STCs.

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