AD/IAI-A/3 - Airframe De-Ice Boots - Pressure Indication Switches (Cth)

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

Israel Aircraft Industries 1125 (Astra) Series Aeroplanes

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.

AD/IAI-A/3 Airframe De-Ice Boots - Pressure Indication Switches

7/2000

Applicability: Model 1125 and Astra SPX aeroplanes with Serial Numbers 004 through 115 inclusive.

Requirement: If not previously accomplished, replace all the inflation pressure indication switches of the airframe de-ice boots system with switches Part Number V25W787003-005 in accordance with Astra Alert Service Bulletin 1125-30A-199 dated 17 April 2000.

Note: Israel CAA AD 30-00-02-05 refers.

Compliance: Before 7 March 2001.

This Airworthiness Directive becomes effective on 13 July 2000.

Background: Existing indication on the switches of the de-icing boots system operate at 13±1 PSIG whereas, according to the de-icing boot's manufacturer, 15 PSIG is the required pressure for effective de-icing. Therefore, indication of normal system operation may be misleading when the system is operating at reduced pressure and ice removal capability may be insufficient throughout the aeroplanes certified envelope of ice conditions.