Airworthiness Directives; McDonnell Douglas Model DC-9-11, -12, -13, -14, -15, and -15F Airplanes; Model DC-9-21 Airplanes; Model DC-9-31, -32, -32 (VC-9C), -32F, -32F (C-9A, C-9B), -33F, -34, and -34F Airplanes; Model DC-9-41 Airplanes; Model DC-9-51 Airplanes; Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) Airplanes; and Model MD-88 Airplanes
airworthiness · Rule · Final rule. · Published 2003-01-02 · Effective 2003-02-06 · 68 FR 33
Document
Document number
02-32865
Federal Register citation
68 FR 33
Type
Rule
Action
Final rule.
Category
airworthiness
Publication date
2003-01-02
Effective date
2003-02-06
FAA docket
Docket No. 99-NM-90-AD
Abstract
This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas airplanes, that requires replacement of certain power relays, and subsequent repetitive cleaning, inspecting, repairing, and testing of certain replaced power relays. This amendment is prompted by reports indicating that the alternating current (AC) cross-tie relay shorted out internally, which caused severe smoke and burn damage to the relay, aircraft wiring, and adjacent panels. The actions specified by this AD are intended to prevent internal arcing of the left and right generator power relays, auxiliary power relays, and external power relays, and consequent smoke and/or fire in the cockpit and cabin.