# AD 85-01-05: Engine Fire Protection System Inspection

- Type: Airworthiness directive
- Status: Current
- Products: Textron BAe.125 Series 800A
- Effective: May 13, 1985
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-5047
- Registered aircraft: 84 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/16A6E92A3A611345862569F3004C66A7.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/85-01-05

## The airworthiness directive

85-01-05 BRITISH AEROSPACE: Amendment 39-5047. Applies to Model 125 800A series airplanes with manufacturer serial numbers 258003 through 258020, certificated in all categories. To detect the lack of engine fire protection caused by improper wiring which would result in the wrong fire bottle operating, accomplish the following, unless previously accomplished:

      (A). Within ten (10) hours time in service after the effective date of this AD, inspect and rewire, if necessary, the electrical circuits of the engines' fire protection system, in accordance with the accomplishment instructions of British Aerospace 125 Service Bulletin 26-A25(253028), dated December 20, 1984.

      (B). Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections required by this AD.

      (C). Alternate inspections, modifications, or other actions which provide an acceptable level of safety may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region.

All persons affected by this directive who have not already received these documents from their manufacturer may obtain copies upon request to British Aerospace, Inc., Librarian, Box 12414, Dulles International Airport, Washington, D.C. 20041.

This amendment becomes effective May 13, 1985, and was effective earlier to those recipients of AD 85-01-05 dated January 15, 1985, distributed by priority letter.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A3EU](https://openairdocs.org/tcds/A3EU): Textron Aviation Inc.; names 1 of 50 models: BAe.125 Series 800A (U-125)

## 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: 84 (84 by airframe model, 0 by engine model)
- Makers: British Aerospace 66, Corporate Jets 8, Raytheon Corporate Jets 8, Raytheon 2

Models with the most aircraft:

- [British Aerospace BAE 125 SERIES 800A](https://openairdocs.org/model/british-aerospace-bae-125-series-800a): 61 aircraft (airframe model)
- [Corporate Jets BAE 125-800A](https://openairdocs.org/model/corporate-jets-bae-125-800a): 8 aircraft (airframe model)
- [Raytheon Corporate Jets BAE 125-800A](https://openairdocs.org/model/raytheon-corporate-jets-bae-125-800a): 8 aircraft (airframe model)
- [British Aerospace BAE 125-800A](https://openairdocs.org/model/british-aerospace-bae-125-800a): 5 aircraft (airframe model)
- [Raytheon BAE 125-800A](https://openairdocs.org/model/raytheon-bae-125-800a): 2 aircraft (airframe model)

All 6 models: https://openairdocs.org/ad/85-01-05/models.md
Every aircraft: https://openairdocs.org/ad/85-01-05/aircraft.md

Its text cites no advisory circulars or STCs.

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