AL 2006-05
20 September 2006
AC Generator Cable Chafing
This Service Difficulty Alert is applicable to CL600-2B16 (601-3A), however, installation is similar in all Bombardier Challenger business aircraft.
Transport Canada has learned through the Service Difficulty Reporting System (SDRS), of an operator of a Bombardier CL600-2B16 (601-3A) Challenger aircraft experienced a number 2 generator failure during flight.
The right generator tripped offline during approach, the generator off enunciator came on, and power auto-transferred to generator 1, with no loss of power on any aircraft buses. The aircraft was ferried to a service center with generator 2 selected off.
Maintenance troubleshooting with extensive ground runs could not duplicate the problem. On the third engine run, the problem was duplicated and isolated to a wiring defect, P/N WIRE 2XA80ABBLU.
The main generator feed cables AWG 8 were inspected at FS 625.30 aft of the aft pressure bulkhead where evidence of arcing from feeder cable to aircraft structure was found. The arcing removed approximately 0.780 square inches (20 mm) of material from the structure. The problem appeared to be incorrect installation of feeder cables with inadequate clearance between cable routing and aircraft structure. The opposite side was inspected and found all cables had adequate clearance between the structures.
Bombardier Aerospace was notified of the potential fleet problem by the operator and Advisory Wire AW600-24-2281 was issued July 20, 2006.
Transport Canada highly recommends all challenger operators inspect this area at the earliest possible convenience to prevent any loss of ac power due to chafing. Adequate clearance and proper protection of cables will prevent chafing and costly downtime.
For further information, please contact a Transport Canada Centre (TCC), or contact Mr. Steve Dudka, Continuing Airworthiness, Ottawa, Ontario, Telephone 613 952-4361, facsimile 613 996-9178 or e-mail dudkas@tc.gc.ca.
For Director, National Aircraft Certification
A. Wan
Acting Chief, Continuing Airworthiness
Note: For the electronic version of this document, please consult the following Web address: https://tc.canada.ca/en/aviation/aircraft-airworthiness/aircraft-certification