Airworthiness Directive · Amendment 39-17563 · Fire protection
Bombardier, Inc. Airplanes
This AD applies to Bombardier, Inc. Model DHC-8-400, -401, and -402 airplanes, certificated in any category, serial numbers (S/Ns) 4001 through 4399 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 advance pneumatic detectors (APDs) for engine fire/ overheat detector assemblies failing to reset after activation due to permanent deformation of the detector switch diaphragm after being exposed to high temperatures. This AD requires replacing all three APDs with new detector assemblies. We are issuing this AD to prevent a continued engine fire indication in the cockpit after the actual fire has been extinguished, which is misleading and might influence the pilot to conduct a potentially hazardous "off-airport" landing.
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 30 months after the effective date of this AD, whichever occurs first, replace the APDs as specified in paragraphs (g)(1), (g)(2), and (g)(3) of this AD, as applicable.
(1) For airplanes having S/Ns 4001 through 4373 inclusive: For the nacelle of the engine primary zone, remove any APD having part number (P/N) 10-1098 and install a new APD having P/N 10-1098-01, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84-26-08, Revision B, dated September 24, 2012.
(2) For airplanes having S/Ns 4001 through 4373 inclusive: For the nacelle of the landing gear primary zone, remove any APD having P/N 10-1097 or 10-1097-01 and install a new APD having P/N 10-1097-02, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84-26-09, Revision A, dated May 12, 2011.
(3) For all airplanes: For the propeller engine controller, remove any APD having P/N 10-1096, 10-1096-01, or 10-1096-02 (serial number is all numeric characters), and install a new APD having P/N 10-1096-02 (serial number is three alpha and four numeric characters), in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84-26-12, Revision B, dated October 12, 2012.
