Airworthiness Directive · Amendment 39-12023 · McDonnell Douglas Model MD-11 Series Airplanes
McDonnell Douglas Model MD-11 Series Airplanes
Model MD-11 series airplanes, as listed in Boeing Alert Service Bulletin MD11-24A144, dated May 2, 2000; 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 (b) 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 series airplanes, that requires an inspection of the one phase remote control circuit breaker (RCCB) in the main avionics compartment and center accessory compartment to determine its part number and serial number, and replacement of the RCCB with a certain RCCB, if necessary. This action is necessary to ensure that defective braze joints of certain latch assemblies of the RCCB are not installed on the airplane. Defective braze joints could fail and prevent the RCCB from tripping during an overload condition, which could result in a fire and smoke in certain wire bundles that are routed to and from the main avionics compartment or center accessory compartment. This action is intended to address the identified unsafe condition.
To prevent fire and smoke in certain wire bundles that are routed to and from the main avionics compartment or center accessory compartment, accomplish the following:
(a) Within 6 months after the effective date of this AD, perform a one-time general visual inspection of the one phase remote control circuit breaker (RCCB) in the main avionics compartment and center accessory compartment to determine the part number and serial number (identified in Table 2 of the Accomplishment Instructions of the service bulletin), in accordance with Boeing Alert Service Bulletin MD11-24A144, dated May 2, 2000.
Note 2: For the purposes of this AD, a general visual inspection is defined as “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or drop-light, and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”
(1) If any RCCB has a part number listed in Table 2 of the Accomplishment Instructions of the service bulletin and the corresponding serial number is NOT identified in that table, no further action is required by this AD.
(2) If any RCCB has a part number listed in Table 2 of the Accomplishment Instructions of the service bulletin and the corresponding serial number is identified in that table, before further flight, replace the RCCB with a RCCB having the same part number with a serial number that is NOT identified in Table 2, in accordance with the service bulletin.
