AD/CL-600/24 - Generator and APU Feeder Wires (Cth)

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

Bombardier (Canadair) CL-600 (Challenger) Series Aeroplanes

AD/CL-600/24 Generator and APU Feeder Wires 12/92

Applicability: All Model CL-600-1A11 and CL-600-2A12 aircraft.

Requirement: 1. Inspect the installation of the Generator 1, Generator 2 and APU No 8 feeder wires for conformance with Canadair Drawings 600-5801 Note 17 or 600-58031 Note 14, and CL-600 Completion Centre Handbook section 6.

2. If any Generator 1, Generator 2 or APU No 8 feeder wires are not installed in accordance with the above requirements, either:

(a) Re-route wires or modify interior installation to provide adequate air space surrounding the wires; or

(b) Install appropriate larger gauge wires of an acceptable type to ensure that the maximum generator rated load can be conducted without causing wire overheat.

Note: Transport Canada AD CF-82-12R1 dated 28 August 1992 refers.

Compliance: Prior to 24 December 1992.

Background: The generator and APU feeder wires are rated for 200C maximum operating temperature. CL-600 type approval tests have shown that when the wires are installed in accordance with the Canadair requirements, wire temperatures of up to 160C can be reached during maximum generator load conditions.

If the Canadair requirements are not complied with when installing interior insulation and furnishing, the No 8 feeder wires for the generators and the APU may overheat during high generator load conditions, due to inadequate airspace surrounding the wires. This overheating may result in degraded wire insulation and damage to insulation blankets, cabin furnishing, or other materials adjacent to the wires.