# AD 86-21-05: Forward Engine Mounts

- Type: Airworthiness directive
- Status: Current
- Products: BH.125 Series 400A, BH.125 Series 600A, DH.125 Series 1A, DH.125 Series 1A/R-522, DH.125 Series 1A/S-522, DH.125 Series 1A-522, DH.125 Series 3A, DH.125 Series 3A/R, DH.125 Series 3A/RA, DH.125 Series 400A, HS.125 Series 600A and HS.125 Series 700A
- Effective: October 20, 1986
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-5418
- Registered aircraft: 26 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/4DCFCBA27ACF9C84862569F3004D07E0.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/86-21-05

## The airworthiness directive

86-21-05 BRITISH AEROSPACE: Amendment 39-5418. Applies to BAe Models DH/HS/BH 125 series airplanes equipped with Garrett TFE 731-3R-1H engines, certificated in any category. Compliance is required within 60 days after the effective date of this AD. To prevent failure of the forward engine mounts, accomplish the following, unless previously accomplished:

A. Inspect the forward engine mounts and repair, if necessary, in accordance with BAe Service Bulletin 71-38, Revision 1, dated October 4, 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 the inspections and/or modifications required by this AD.

All persons affected by this directive, who have notalready 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 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 October 20, 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 12 of 50 models: HS.125 Series 600A, HS.125 Series 700A, DH.125 Series 1A/R-522, BH.125 Series 400A, BH.125 Series 600A, DH.125 Series 400A, DH.125 Series 3A/R, DH.125 Series 1A…

## 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: 26 (26 by airframe model, 0 by engine model)
- Makers: British Aerospace 14, Hawker Siddeley 11, Raytheon 1

Models with the most aircraft:

- [British Aerospace HS 125-700A](https://openairdocs.org/model/british-aerospace-hs-125-700a): 14 aircraft (airframe model)
- [Hawker Siddeley HS.125 SERIES 700A](https://openairdocs.org/model/hawker-siddeley-hs-125-series-700a): 7 aircraft (airframe model)
- [Hawker Siddeley BH.125-400A](https://openairdocs.org/model/hawker-siddeley-bh-125-400a): 2 aircraft (airframe model)
- [Hawker Siddeley DH.125-3A/RA](https://openairdocs.org/model/hawker-siddeley-dh-125-3a-ra): 2 aircraft (airframe model)
- [Raytheon HS 125-700A](https://openairdocs.org/model/raytheon-hs-125-700a): 1 aircraft (airframe model)

All 5 models: https://openairdocs.org/ad/86-21-05/models.md
Every aircraft: https://openairdocs.org/ad/86-21-05/aircraft.md

Its text cites no advisory circulars or STCs.

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