AD 2001-17-20 Airworthiness Directives; Boeing Model 707 and 720 Series Airplanes

Models named: 707, 720 series. Read the applicability below — it usually turns on serial or part numbers too.

Model 707 and 720 series airplanes, line numbers 1 through 941 inclusive, 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.

Required as indicated, unless accomplished previously. To detect and correct damaged wiring for the fuel boost pumps and override pumps, which could cause electrical arcing that could puncture the conduit containing the wire and result in an explosion or fire adjacent to the fuel tank, accomplish the following: Replacement of Wiring, Installation of Sleeving, and Associated Actions (a) Within 1 year or 4,000 flight hours after the effective date of this AD, whichever occurs first, replace the wiring for the fuel boost pumps and override pumps, install Teflon sleeving over the wiring, and do all associated actions, per the Accomplishment Instructions of Boeing Service Bulletin A3500, Revision 1, dated April 26, 2001. The associated actions include performing a general visual inspection of the area around each fuel boost pump and override pump for evidence of a fuel leak; finding the source of any fuel leak and repairing the affected area; replacing the conduit, if required; and performing a detailed visual inspection of the wiring installed in the conduit for evidence of electrical arcing or a fuel leak, or exposed copper wire. If replacement of the conduit is deferred per the service bulletin, repeat the inspection for fuel leaks every 500 flight hours until the conduit is replaced, and replace the conduit within 6,000 flight hours or 18 months, whichever occurs first. 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.” Note 3: For the purposes of this AD, a detailed visual inspection is defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.” Note 4: Use of Boeing Alert Service Bulletin A3500, dated July 27, 2000, to accomplish the actions required by this AD prior to the effective date of this AD is considered acceptable for compliance with this AD. Repetitive Inspections (b) After replacement of the wiring per paragraph (a) of this AD, repeat the detailed visual inspection of the wiring for the fuel boost pumps and override pumps for damage, such as evidence of electrical arcing or exposed copper wire, or evidence of a fuel leak. Repeat the inspection at least every 30,000 flight hours, per the Accomplishment Instructions of Boeing Service Bulletin A3500, Revision 1, dated April 26, 2001. If any electrical arcing or exposed copper wire or evidence of a fuel leak is detected during any inspection per this paragraph, before further flight, do the applicable corrective actions (including finding the source of any fuel leak and repairing the affected area, replacing the wiring, replacing the conduit, or installing new Teflon sleeving; as applicable) according to the Accomplishment Instructions of the service bulletin. Alternative Methods of Compliance (c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO. Note 5: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. Special Flight Permits (d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. Incorporation by Reference (e) The actions shall be done in accordance with Boeing Service Bulletin A3500, Revision 1, dated April 26, 2001. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. Effective Date (f) This amendment becomes effective on October 1, 2001. Issued in Renton, Washington, on August 17, 2001. Vi L. Lipski, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 01-21395 Filed 8-24-01; 8:45 am] BILLING CODE 4910-13-P