# AD 86-14-06: Electronic Flight Instrument System

- Type: Airworthiness directive
- Status: Current
- Products: Textron BAe.125 Series 800A
- Effective: August 8, 1986
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-5351
- Registered aircraft: 84 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/70333706C03BAD4B862569F3004CBED6.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/86-14-06

## The airworthiness directive

86-14-06 BRITISH AEROSPACE: Amendment 39-5351. Applies to Model BAe 125- 800A series airplanes with manufacturer serial numbers listed in British Aerospace 125 Service Bulletin 24-248-(3024), dated March 8, 1985, certificated in any category. To prevent complete loss of power to the Electronic Flight Instrument System (EFIS), accomplish the following within the next 60 days after the effective date of this AD, unless previously accomplished:

A. Perform the following actions as applicable:

1. For airplanes with manufacturer serial numbers 258003 and 258010, and for airplanes which have utilized power supplies HN1/HP1, the existing heat-sink must be replaced with a new sub-assembly, as described in Part A of the accomplishment instructions of British Aerospace Service Bulletin 24-248-(3024), dated March 8, 1985; or

2. If power supplies HN1/HP1 have not been utilized, the existing heat-sink assembly and associated power supply cabling from ground supply contactor "E"on panel GA must be replaced in accordance with Part B of the accomplishment instructions of British Aerospace Service Bulletin 24-248-(3024), dated March 8, 1985.

B. An alternate means 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, Northwest Mountain Region.

C. 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 and/or modifications required by this AD.

All persons affected by this directive, who have not already received the appropriate service document from the manufacturer, may obtain copies upon request to British Aerospace, Inc., Librarian, Box 17414, Dulles International Airport, Washington, D.C. 20041. This document may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington.

This amendment becomes effective August 8, 1986.

## 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/86-14-06/models.md
Every aircraft: https://openairdocs.org/ad/86-14-06/aircraft.md

Its text cites no advisory circulars or STCs.

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