# AD 59-12-03: Fire Extinguisher

- Type: Airworthiness directive
- Status: Current
- Products: Vickers-Armstrongs Viscount 745D and Viscount 810
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0A65606405635CE88625699A00652599.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/59-12-03

## The airworthiness directive

59-12-03 VICKERS: Applies to All Viscount 745D and 810 Series Aircraft.

Compliance required by October 31, 1959.

Two cases have occurred of the Graviner fire extinguisher cartridge types A216 and A217 failing to operate at altitudes exceeding 20,000 feet. The failures were due to a combination of altitude and temperature affecting the gunpowder charge. To preclude such failures the Graviner Manufacturing Company has issued Modification AU 393 introducing improved firing units type A716 (replacing type A216) and type A717 (replacing A217). The new units have a modified bridge wire arrangement and may be identified by a blue plastic band around the neck of the cartridge. The British Air Registration Board considers the embodiment of this modification mandatory.

(Graviner Manufacturing Company Modification No. AU 393 and Vickers-Armstrongs PTL205 and Modification D.2926 (700 Series) and PTL 73 and Modification FG.1695 (800/810 Series) covers this subject.)

## 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 810, 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.

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