# AD 69-16-05: Lower Gear Box and Oil Outlet Magnetic Plugs

- Type: Airworthiness directive
- Status: Current
- Products: Rolls-Royce 250-C18
- Effective: August 30, 1969
- Superseded by: Nothing supersedes this AD
- Product type: Engine
- Amendment: 39-829
- Registered aircraft: 82 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/C86C58A29F98C1D486256E0100547596.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/69-16-05

## The airworthiness directive

69-16-05 ALLISON: Amdt. 39-829. Applies to Model 250-C18 engines installed in Bell Model 206A Helicopters. Compliance: Required as indicated. To detect incipient engine failure, accomplish the following: A) Effective immediately upon receipt of this Airworthiness Directive, inspect the lower gear box and the oil outlet magnetic plugs on a daily basis as described in Allison Commercial Service Letter 250 CSL No. 6, dated January 12, 1967. This inspection shall be performed at time intervals not to exceed five (5) hours' time in service. B) On or before November 3, 1969, install a visual magnetic plug indicator as described in Bell Service Letter 206A-129, dated August 11, 1969, or later FAA approved revision or an equivalent installation approved by Chief, Engineering & Manufacturing Branch, FAA, Central Region. C) When the installation described in Paragraph B of this Airworthiness Directive has been accomplished, the inspections required by Paragraph A of this Airworthiness Directive will no longer be required. Effective August 13, 1969, revised August 30, 1969.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS E4CE](https://openairdocs.org/tcds/E4CE): Rolls-Royce Corporation; names 1 of 23 models: 250-C18

## 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: 82 (0 by airframe model, 82 by engine model)
- Makers: Bell 31, Hiller 15, Enstrom Helicopter 9, Cessna 7, Beech 6, Siai-Marchetti 3, Hughes 2, Ardoyno John W 1, Huizenga Mike 1, Maule 1

Models with the most aircraft:

- [Allison 250 series](https://openairdocs.org/engine/allison-250-series): 79 aircraft (engine model)
- [Allison 250-C18](https://openairdocs.org/engine/allison-250-c18): 2 aircraft (engine model)
- [Rolls-Royce 250-C18](https://openairdocs.org/engine/rolls-royce-250-c18): 1 aircraft (engine model)

All 4 models: https://openairdocs.org/ad/69-16-05/models.md
Every aircraft: https://openairdocs.org/ad/69-16-05/aircraft.md

Its text cites no advisory circulars or STCs.

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