Landing gear wheel assembly

Effectivity: Challenger 600/601/604/605/650 aircraft  

ATA 32 

By: Victor Silva (CSE) 

Bombardier Technical Services would like to remind all maintenance personnel the importance of ensuring adequate landing gear wheel bearing lubrication and that wheel assembly installation must follow the recommendations provided by the aircraft maintenance manual (AMM) associated tasks as well as the original equipment manufacturer component maintenance manual (CMM), to ensure serviceability during aircraft operation. 

There has been one isolated event reported to Bombardier where a Challenger 600XX series aircraft had one main wheel assembly detach after takeoff roll during initial climb-out. The operator did confirm that there had been maintenance performed on that specific main wheel assembly a few cycles before the event.  This resulted in an outer bearing failure which caused the main wheel assembly to slide off the brake assembly/axle on lift-off.  The aircraft performed a normal flight and an uneventful landing at destination.  Recommended inspections and actions were then complied with prior to aircraft return to service.  

This rare event of a MLG wheel assembly detachment is not directly related to normal operation of the aircraft and the most probable cause may have been improper maintenance actions during wheel installation, such as inadequate bearing wheel bearing lubrication and/or axle nut torque not applied in accordance AMM requirements.   

Please advise maintenance personnel that proper wheel assembly bearing lubrication/ installation as instructed in AMM and CMM are essential in eliminating the risk of similar events during aircraft operation.