AV 2000-04
17 August 2000
Burnt power supply
Transport Canada has recently received a Service Difficulty Report regarding a burnt reading light power supply mounted in the 1R door of an A330 Series 200 aircraft.
During an inspection following a report of the failed light, the power supply for the reading light, P/N F9259004601200 (ref. IPC XF 31-10-01-71C) was found severely overheated with extensive damage. The associated circuit breaker did not open. A fleet campaign by the operator failed to turn up any other occurrences. However, some of the reading lights and the insulation blankets in the vicinity were found to be very wet, which may have led to a short circuit in the power supply.
An investigation by the manufacturer of the failed unit has indicated that the short circuit was due to moisture ingress. An improved coating process has been introduced on units date-coded after 01/2000.
Transport Canada strongly recommends that operators of A330 aircraft inspect this area at their earliest convenience and repair as required. Any finding should be reported to Transport Canada by submitting a Service Difficulty Report (SDR).
For further information contact a Transport Canada Centre, or Mr. Paul Jones, Continuing Airworthiness, Ottawa, telephone (613) 952-4431, facsimile (613) 996-9178 or e-mail jonesp@tc.gc.ca.
For Director, Aircraft Certification
B. Goyaniuk
Chief, Continuing Airworthiness