Airworthiness Directive · Amendment 39-18834 · Lights
Bombardier, Inc. Airplanes
This AD applies to Bombardier, Inc. Model DHC-8-400, -401, and -402 airplanes, certificated in any category, serial numbers 4001, and 4003 through 4507 inclusive.
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 interior emergency lights remaining "ON" following routine operational checks of the emergency light system. This AD requires changing the wiring gauge for the affected emergency lights power supplies wiring to prevent overheating in the wires. We are issuing this AD to address the unsafe condition on these products.
Within 6,000 flight hours or 36 months, whichever occurs first, after the effective date of this AD, incorporate Bombardier Modification Summary 4-126620 to replace affected wires with a heavier wire gauge, in accordance with paragraph 3.B. of the Accomplishment Instructions of Bombardier Service Bulletin 84-33-12, Revision B, dated June 28, 2016.
