COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
British Aerospace BAe 146 Series Aeroplanes
AD/BAe 146/64 Pitot-Static System - True Airspeed Computer No.2
10/96
Applicability: This Directive is applicable to BAe 146 Series 100, 100A, 200, 200A, 300 and 300A aeroplanes equipped with a True Airspeed (TAS) Computer No 2 installed in accordance with BAe Avro modification HCM40160C (SB.34-52-40160C) or HCM40298G and where a Dual Mode `S' Transponder has been installed in accordance with BAe Avro modification HCM30118B (SB.34-90-30118B) or HCM40277A (SB.34-91-40277A).
Note: The requirements of this Directive were incorporated prior to delivery on constructors number E3198 and subsequent aeroplanes, if the modifications referenced above were also incorporated.
Requirement: Install new pitot and static lines between the TAS 2 unit and the drain valve in accordance with either British Aerospace (Commercial Aircraft) Limited, Modification Service Bulletin SB.34-132-46042A dated 24 June 1991 or British Aerospace, Regional Aircraft Limited, Avro International Division, Modification Service Bulletin SB.34-132-46042A Revision 2 dated 1 July 1996.
Note: Both Service Bulletins have been classified as mandatory by the CAA(UK).
Compliance: Unless previously accomplished, then prior to 31 December 1996.
This directive becomes effective on 12 September 1996.
Background: The introduction of the Mode `S' transponder resulted in the TAS 2 unit being moved from its position on the avionics rack. This resulted in the pitot and static flexible hoses between the TAS 2 unit and the drain valve forming an unacceptable water trap. This Directive introduces new shorter flexible hoses designed to minimise the likelihood of water being trapped.