# AD 56-19-01: Aileron Pulley Locking Pin

- Type: Airworthiness directive
- Status: Current
- Products: de Havilland Aircraft Co., Ltd., The D.H. 104 Dove Series 1A, D.H. 104 Dove Series 2A, D.H. 104 Dove Series 5A, D.H. 104 Dove Series 5BA, D.H. 104 Dove Series 6A, D.H. 104 Dove Series 6BA, D.H. 104 Dove Series 7A, D.H. 104 Dove Series 7AXC, D.H. 104 Dove Series 8A and D.H. 104 Dove Series 8AXC
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Registered aircraft: 3 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/97EBDB7D46E7986186256A34006BD48B.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/56-19-01

## The airworthiness directive

56-19-01 de HAVILLAND: Applies to All Model 104 "Dove" Aircraft.

Compliance required as indicated below.

A case has occurred in which the mild steel rivet locking the stud, P/N 4CF.607 to the spindle, P/N 4CF.603ND in the aileron differential pulley assembly has sheared, allowing the spindle to unscrew from the stud to such an extent that it, together with the pulley, was on the point of becoming disengaged from the pulley bracket.

To prevent a recurrence of this defect, compliance with Dove Modification No. 765 (installation of a H.T.S. pin for locking stud on aileron differential pulley spindle) is considered mandatory by the British Air Registration Board in which the FAA concurs. Accordingly, unless already accomplished, Modification No. 765 should be embodied on all Dove aircraft as soon as possible, but not later than October 15, 1956.

(Dove Modification 765 is covered in de Havilland Service Technical News Sheet CT (104) No. 114 dated November 1, 1954.)This supersedes AD 55-02-01.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-807](https://openairdocs.org/tcds/A-807): Acro Aeronautical Services Ltd; names 10 of 10 models: D.H. 104 Dove Series 8A, D.H. 104 Dove Series 7A, D.H. 104 Dove Series 1A, D.H. 104 Dove Series 5A, D.H. 104 Dove Series 7AXC, D.H. 104 Dove Series 8AXC, D.H. 104 Dove Series 2A, D.H. 104 Dove Series 5BA…

## 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: 3 (3 by airframe model, 0 by engine model)
- Makers: Dehavilland 3

Models with the most aircraft:

- [Dehavilland DH104 DOVE 6A](https://openairdocs.org/model/dehavilland-dh104-dove-6a): 3 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/56-19-01/models.md
Every aircraft: https://openairdocs.org/ad/56-19-01/aircraft.md

Its text cites no advisory circulars or STCs.

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