Airworthiness Directive · Amendment 39-16935 · 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 4095 through 4391 inclusive.
We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-400, -401, and -402 airplanes. This AD requires an inspection of a certain alternating current (AC) power wire bundle for damage, and repair if necessary. Additionally, this AD requires segregating the wire bundle into two wire bundles and installing Teflon tubing. This AD was prompted by multiple reports of the loss of certain AC systems caused by a burnt AC power wire bundle. We are issuing this AD to prevent the loss of ice protection systems for the angle of attack vanes, pitot probes, engine inlets, and windshields, and consequent loss of or misleading airspeed indication and increased workload for the flight crew, which could lead to loss of control of the airplane.
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 400 flight hours or 60 days, whichever occurs first, after the effective date of this AD, do the actions specified in paragraphs (g)(1) and (g)(2) of this AD.
(1) Do a detailed inspection of the affected AC power wire bundle for damage (any foreign object damage (FOD), damage due to sharp bends and kinking or deterioration, insulation cracking, evidence of heat damage to the insulation, and chafing) and do all applicable repairs, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84-24-52, dated November 22, 2011. Do all applicable repairs before further flight.
(2) Segregate the AC power wire bundle into two bundles and install Teflon tubing, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84-24-52, dated November 22, 2011.
