Airworthiness Directive · Amendment 39-17214 · Electrical power
Bombardier, Inc. Airplanes
This AD applies to Bombardier, Inc. Model DHC-8-400, -401, and -402 airplanes; certificated in any category; serial numbers 4001 through 4338 inclusive, with Honeywell alternating current (AC) generator part number (P/N) 1152218-3, 1152218-4 or 1152218-5 installed.
We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-400 series airplanes. This AD was prompted by reports of alternating current (AC) generator failures in-service due to incomplete fusion in the weld joint of the rotor band assembly. This AD requires inspecting the AC generator to determine the part number, and replacing the AC generator if necessary. We are issuing this AD to prevent rotor windings from coming in contact with the generator housing, which could result in debris contaminating and potentially blocking the engine oil scavenge system, leading to loss of oil pressure and an in-flight shutdown of the engine.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Within 6,000 flight hours or 36 months after the effective date of this AD, whichever occurs first: Inspect the left and right AC generators to determine if the AC generator has a part number identified in step 3.B.(2) of the Accomplishment Instructions of Bombardier Service Bulletin 84-24-45, dated January 13, 2011, or has P/N 1152218-3. If an AC generator has a part number identified in Bombardier Service Bulletin 84-24-45, dated January 13, 2011, or has P/N 1152218-3, before further flight, replace the AC generator with a modified or new AC generator having P/N 1152218-6, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84-24-45, dated January 13, 2011.
