# AD 58-10-06: Flap Switch Lever

- Type: Airworthiness directive
- Status: Current
- Products: Vickers-Armstrongs Viscount 744 and Viscount 745D
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/BE62C992B430AE488625699A0063F4F9.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/58-10-06

## The airworthiness directive

58-10-06 VICKERS: Applies to All Viscount 700 Series Aircraft.

Compliance required as soon as possible but not later than July 31, 1958.

A case has occurred during production on the Viscount 700 Series aircraft, of the fracturing of the cranked operating lever (P/N N.69195) of the flap selector switch, Type D.7406. Investigation has established that the fracture is the result of excessive case-hardening of the mild steel lever (P/N N.69195) such that the lever became brittle. The hardened mild steel lever (P/N N.69195) must be replaced by a mild steel lever (P/N N.69195/1) which is identified by a blue spot on the outside face of the lever crank which is visible when positioned in the throttle pedestal.

Vickers-Armstrong Aircraft Ltd. PTL No. 188 and Modification Bulletin No. D.2673 cover the same subject. This modification is considered mandatory by the British Air Registration Board. The FAA concurs and considers compliance mandatory.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-814](https://openairdocs.org/tcds/A-814): Vickers-Armstrongs (Aircraft Limited); names 2 of 3 models: Viscount 744, Viscount 745D

## Registered aircraft it may apply to (OpenAirDocs)

No registered aircraft matched the models it names.

Its text cites no advisory circulars or STCs.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.