AD/IAI-A/15 - Oxygen Shut-off Valve (Cth)

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES

AIRWORTHINESS DIRECTIVE

For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Israel Aircraft Industries 1125 (Astra) Series Aeroplanes

AD/IAI-A/15 Oxygen Shut-off Valve 11/2002

Applicability: 1125 Astra aeroplanes, with serial numbers (S/N) 004 to 072 and 074 to 078 inclusive, and Astra SPX aeroplanes, with S/N 073 and 079 to 131 inclusive.

Requirement: Remove the existing oxygen shut-off valve and replace it with a Scott® slow opening valve having part number 27550-3 in accordance with Astra Alert Service Bulletin 1125-35A-114 dated 28 November 2001.

Note: Israel CAA AD 35-02-07-02 refers.

Compliance: Within 200 hours time in service after the effective date of this Directive.

This Airworthiness Directive becomes effective on 31 October 2002.

Background: The oxygen system of the Astra is designed so that high oxygen pressure is maintained from the cylinder to the pressure reducer-regulator located downstream of the shut-off valve. If this valve is quickly opened, overheating and subsequent fire may occur due to rapid adiabatic compression.