# AD 92-06-04: Dimmer System

- Type: Airworthiness directive
- Status: Current
- Products: Textron BAe.125 Series 800A, BAe.125 Series 800A (C-29A) and BAe.125 Series 800A (U-125)
- Effective: April 21, 1992
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-8184
- Docket: 91-NM-206-AD
- Registered aircraft: 84 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/7734CBDC447FDFDF86256A09006B2720.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/92-06-04

## The airworthiness directive

92-06-04 BRITISH AEROSPACE: Amendment 39-8184. Docket No. 91-NM-206-AD.

Applicability: Model BAe 125-800A series airplanes, Post-Modification 253191A and Pre-Modification 253247A, certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent internal arcing in the dimmer units and smoke emission into the cockpit, accomplish the following:

  (a) Within 60 days after the effective date of this AD, modify the instrument integral lighting system by installing dimmer units having Page Modification AR1477 incorporated, and perform functional tests of the pilot's and co-pilot's instrument integral lighting dimmer system, in accordance with British Aerospace Service Bulletin 33-44-7670A, Revision 1, dated April 4, 1991.

  (b) An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. The request shall be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Standardization Branch.

  (c) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished.

  (d) The modification shall be done in accordance with British Aerospace Service Bulletin 33- 44-7670A, Revision 1, dated April 4, 1991. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from British Aerospace, PLC, Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, DC 20041-0414. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington; or at the Office of the Federal Register, 1100 L Street NW., Room 8401, Washington, DC.

  (e) This amendment becomes effective on April 21, 1992.

## 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/92-06-04/models.md
Every aircraft: https://openairdocs.org/ad/92-06-04/aircraft.md

Its text cites no advisory circulars or STCs.

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