# AD 80-25-08: Tension-Torsion Strap Assemblies

- Type: Airworthiness directive
- Status: Current
- Products: Columbia Helicopters 107-II
- Effective: December 12, 1980
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-3987
- Registered aircraft: 12 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/55EF43FC094735E186256A4E004E3A19.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/80-25-08

## The airworthiness directive

80-25-08 BOEING VERTOL (VERTOL): Amendment 39-3987. Applies to Vertol Model 107-II helicopters certificated in all categories.

Compliance required as indicated.

To prevent fatigue failure of the main rotor tension-torsion strap assemblies, remove from service tension-torsion strap assemblies Part No. 107R2003-1 upon the accumulation of 27,800 hours in service and replace with an airworthy part that meets the requirement of this AD.

This amendment is effective December 12, 1980.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 1H16](https://openairdocs.org/tcds/1H16): Columbia Helicopters Inc.; names 1 of 1 models: 107-II

## 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: 12 (12 by airframe model, 0 by engine model)
- Makers: Boeing-Vertol 7, Columbia Helicopters 2, Vertol 2, Boeing V-Columbia Helicopters 1

Models with the most aircraft:

- [Boeing-Vertol 107-II](https://openairdocs.org/model/boeing-vertol-107-ii): 7 aircraft (airframe model)
- [Columbia Helicopters 107-II](https://openairdocs.org/model/columbia-helicopters-107-ii): 2 aircraft (airframe model)
- [Vertol 107-II](https://openairdocs.org/model/vertol-107-ii): 2 aircraft (airframe model)
- [Boeing V-Columbia Helicopters 107-II](https://openairdocs.org/model/boeing-v-columbia-helicopters-107-ii): 1 aircraft (airframe model)

All 4 models: https://openairdocs.org/ad/80-25-08/models.md
Every aircraft: https://openairdocs.org/ad/80-25-08/aircraft.md

Its text cites no advisory circulars or STCs.

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