Airworthiness Directive · Amendment 39-11835 · McDonnell Douglas Model DC-10 Series Airplanes
McDonnell Douglas Model DC-10 Series Airplanes
Model DC-10 series airplanes, as listed in McDonnell Douglas Alert Service Bulletin DC10-24A163, dated July 28, 1999; certificated in any category; except those airplanes that have been converted from a passenger to a cargo-carrying (“freighter”) configuration, and Model DC-10-10F, -30F (KC-10A and KDC-10 military), and -40F series airplanes.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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 DC-10 series airplanes, that requires a general visual inspection of electrical power feeder cables, airplane structure, and insulation blankets at a certain fuselage station to detect chafing and arcing damage, and corrective actions, if necessary; and installation of a standoff and clamp. This amendment is prompted by an incident in which the power feeder cables in the cabin electrical system were found to be chafed and arced against a fuselage frame due to insufficient clearance between the cables and airplane structure. The actions specified by this AD are intended to prevent such chafing and arcing, which could cause smoke and fire in the overhead of the main cabin.
To prevent arcing of the power feeder cables against the fuselage structure, which could cause smoke and fire in the overhead of the main cabin, accomplish the following:
(a) Within 6 months after the effective date of this AD, perform a general visual inspection of the power feeder cables in the cabin electrical system, airplane structure, and insulation blankets at station Y=1099.000 between longerons 9 and 10 (right side) for evidence of chafing and arcing damage, in accordance with McDonnell Douglas Alert Service Bulletin DC10-24A163, dated July 28, 1999.
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 no chafing or damage to the power feeder cables, structure, or insulation blankets is detected: Prior to further flight, install a standoff and clamp at station Y=1093.000, longeron 10, in accordance with Condition 1 of the Work Instructions of the service bulletin.
(2) If any chafed power feeder cable is detected, and if no damage to adjacent structure or insulation blankets is detected: Prior to further flight, repair or replace the power feeder cables in the cabin electrical system with new power feeder cables; and install a standoff and clamp at station Y=1093.000, longeron 10, in accordance with Condition 2 of the Work Instructions of the service bulletin.
(3) If any chafed power feeder cable is detected, and if any damage to the adjacent structure and/or insulation blankets is detected: Prior to further flight, accomplish the actions specified in paragraphs (a)(3)(i), (a)(3)(ii), (a)(3)(iii), and (a)(3)(iv) of this AD, as applicable, in accordance with Condition 3 of the Work Instructions of the service bulletin.
(i) Repair or replace the damaged power feeder cables in the cabin electrical system with new power feeder cables.
(ii) Repair or replace the damaged structure with new structure.
(iii) Repair or replace the damaged insulation blankets with new insulation blankets; however, insulation blankets made of metallized polyethyleneteraphthalate (MPET) may not be used.
(iv) Install a standoff and clamp at station Y=1093.000, longeron 10.
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.
