AD/BN-2/64 Amdt 1 - Propeller Anti-Ice System (Cth)

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

Pilatus Britten-Norman BN-2 Series Aeroplanes

AD/BN-2/64 Amdt 1

Propeller Anti-Ice System 4/99 DM

Applicability: BN2T series Islander aeroplanes without modification NB-M-1662 incorporated.

Requirement: 1. Inspect the electrical cables, cable looms and other components of the propeller anti-ice system in accordance with Pilatus Britten-Norman Aircraft Manufacturers Service Bulletin (SB) BN2/SB.250 dated 6 July 1998.

2. If any of the cables or components are found to be unserviceable during the Requirement 1 inspection, either repair or replace the effected cables or components.

3. Modify the engine intake and propeller anti-ice electrical system in accordance with Britten-Norman SB BN2/SB.250 Issue 2 dated 1 December 1998.

Note: Both SBs have been classified as Mandatory by the CAA(UK) and CAA(UK) AD 005-07-98 also refers.

Compliance: 1. Remains unchanged as 'Before further flight after 11 November 1998'.

2. Remains unchanged as 'Before further flight'.

3. At the next 100 hour inspection after the effective date of this amendment or by 17 June 1999, which ever occurs first.

This Amendment becomes effective on 17 March 1999.

Background: Heat damage has been reported to the left propeller anti-ice electrical cables and cable loom attachments of a BN2T aeroplane. The damage was caused as a result of a electrical short circuit when insulation of one of the harness cables was worn by chafing in the spinner assembly. The applicable fuse did not function and the cables became too hot with the subsequent high current flow.

The original issue of the directive required inspection and, if necessary, repair of anti- ice electrical cables, looms and components. This amendment requires modification of the engine intake and propeller anti-ice electrical system to provide better circuit protection.