Airworthiness Directive · Amendment 39-11574 · McDonnell Douglas Model MD-11 and MD-11F Series Airplanes
McDonnell Douglas Model MD-11 and MD-11F Series Airplanes
Superseded. A later AD replaced this one: AD 2002-14-09. Comply with the one in force.
Model MD-11 and MD-11F series airplanes, as listed in McDonnell Douglas Alert Service Bulletin MD11-24A150, dated March 25, 1999, and McDonnell Douglas Alert Service Bulletin MD11-24A147, dated March 24, 1999; certificated in any category.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model MD-11 and MD-11F series airplanes, that requires replacement of the existing terminal strips and supports above the main cabin area; and installation of spacers between terminal strips and mounting brackets in the avionics compartment; as applicable. This amendment is prompted by a report indicating that, during flight, an incident of electrical arcing occurred at a terminal strip located overhead in the main cabin. The actions specified by this AD are intended to prevent electrical arcing caused by power feeder cable terminal lugs grounding against terminal strip support brackets, which could result in smoke and fire in the main cabin or avionics compartment.
To prevent electrical arcing caused by power feeder cable terminal lugs grounding against terminal strip support brackets, which could result in smoke and fire in the main cabin or avionics compartment, accomplish the following:
(a) For airplanes listed in the effectivity of McDonnell Douglas Alert Service Bulletin MD11-24A150, dated March 25, 1999, on which the modification specified in McDonnell Douglas Service Bulletin MD11-24-085, dated August 1, 1995, has not been accomplished: Within 1 year after the effective date of this AD, replace the existing terminal strips and supports above the main cabin at station Y=5-32.000 with new terminal strips and supports in accordance with McDonnell Douglas Alert Service Bulletin MD11-24A150, dated March 25, 1999.
(b) For airplanes listed in the effectivity of McDonnell Douglas Alert Service Bulletin MD11-24A147, dated March 24, 1999: Within 6 months after the effective date of this AD, install spacers between terminal strips and mounting brackets in the avionics compartment in accordance with the service bulletin.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
