# AD 86-06-04: Flap Drive Torque Shaft

- Type: Airworthiness directive
- Status: Current
- Products: Textron DH.125 Series 1A, DH.125 Series 1A-522, DH.125 Series 1A/S-522 and DH.125 Series 3A
- Effective: September 15, 1986
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-5409
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/43A76E96520AE928862569F3004CA979.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/86-06-04

## The airworthiness directive

86-06-04 BRITISH AEROSPACE: Amendment 39-5409. Applies to British Aerospace Models DH 125-1A, DH 125-1A/522, DH 125-1A/S-522, and DH 125-3A airplanes, all serial numbers, certificated in any category. To prevent loss of control due to asymmetric flaps, accomplish the following, unless already accomplished:

A. Before further flight, inspect the left-hand and right-hand flap drive torque shaft assemblies, and repair or replace, as necessary, in accordance with British Aerospace (BAe) Alert Service Bulletin 27-A140, dated March 10, 1986, or BAe Service Bulletin 27-140, dated April 1, 1986.

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 documents from the manufacturer may obtain copies upon request to British Aerospace, Inc., Librarian, Box 17414, Dulles International Airport, Washington, D.C. 20041. These documents 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 September 15, 1986.

It was effective earlier to those recipients of Priority Letter AD 86-06-04 dated March 19, 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 4 of 50 models: DH.125 Series 1A, DH.125 Series 1A-522, DH.125 Series 3A, DH.125 Series 1A/S-522

## Registered aircraft it may apply to (OpenAirDocs)

No registered aircraft matched the models it names.

Its text cites no advisory circulars or STCs.

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