This AD was prompted by reports of DC motor pump (DCMP) failures during production flight tests. These failures caused the electrical system generators to disconnect due to excessive induced voltage in the bus, caused by the DCMP overheating at high altitudes. The FAA is issuing this AD to address failures of the DCMP and electrical system generators, which could lead to the loss of normal electrical power on the airplane. 

Within 6 months after the effective date of this AD: Install the redesigned DCMP electric motor assembly, having part number (P/N) 945202-3, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 100-29-18, Revision 03, dated December 18, 2014. This is effective 7/6/21.  

This AD can be corrected in 3-4 working days and can be performed at any of the West Star full-service facilities (ALN, GJT, PCD & CHA).

Estimated cost to address AD 2021-10-26 is approximately $28,000.  Contact your West Star Technical Sales Manager today for more information.