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FAA orders · airworthiness directive · historical

99-12-52: Fuel Boost Pump

FAA order 99-12-52 is an airworthiness directive in force since June 28, 1999. The FAA's subject line: Fuel Boost Pump. It names Boeing 727: about 37 aircraft on the U.S. register today, though an order usually covers particular versions or serial numbers rather than every one. System: electrical power.

What it applies to as the FAA lists it

Kind of product
Aircraft
Makes
The Boeing Company
Models
727 Series (all)
On this site
Boeing 727 37 registered

Dates and paperwork

In force since
June 28, 1999
Published
June 23, 1999
Docket
99-NM-121-AD
Replaced by
2007-11-08
Status
Historical
The FAA's document
Read the order on the FAA's site

The FAA's summary their words, unchanged

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) T99-12-52 that was sent previously to all known U.S. owners and operators of all Boeing Model 727 series airplanes by individual telegrams. This AD requires a boost pump dry bay inspection to detect leakage of fuel through an arced-through conduit, and corrective action, as necessary. This AD also requires repetitive detailed visual inspections of the in-tank fuel boost pump wiring to detect chafing of the wire insulation, evidence of electrical arcing, or arc-through of the conduit wall on Model 727 series airplanes, and applicable corrective action; and installation of sleeving over the in- tank fuel boost pump wires as a method to protect the wiring from chafing. This action is prompted by reports of severe wear of in-tank fuel boost pump wiring, and arc-through of the surrounding conduit on two Model 727 series airplanes. The actions specified by this AD are intended toprevent fuel tank explosion resulting from arc-through of the fuel boost pump wiring conduits.

The order itself the regulatory text, as published

Show the full text (6,796 characters)
99-12-52 BOEING: Amendment 39-11199. Docket 99-NM-121-AD. Supersedes Telegraphic AD T99-12-51. \n\n\tApplicability: All Model 727 series airplanes, certificated in any category. \n\n\tNOTE 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 (l) 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. \n\n\tCompliance: Required as indicated, unless accomplished previously.To prevent fuel tank explosion resulting from arc-through of the fuel boost pump wiring conduits, accomplish the following: \n\n\t(a)\tFor airplanes with 50,000 or more total flight hours as of the date of receipt of AD T99-12-51, within 5 days after the effective date of this AD, accomplish the requirements of paragraph (c) of this AD. \n\n\t(b)\tFor airplanes with less than 50,000 total flight hours as of the date of receipt of AD T99-12-51, prior to the accumulation of 30,000 total flight hours, or within 10 days after receipt of this AD, whichever occurs later, accomplish the requirements of paragraph (c) of this AD.\n\nInitial Inspection and Corrective Action \n\n\t(c)\tExcept as provided in paragraphs (d) and (e) of this AD, perform a boost pump dry bay inspection and applicable follow-on corrective actions, in accordance with steps 1 through 6 of the "Boost Pump Dry Bay Inspection," specified in Boeing All Operator Message M-7200-99-04035, dated May 21, 1999, or in accordance with Boeing Alert Service Bulletin 727-28A0126, dated May 24, 1999. \n\n\t(d)\tFor airplanes on which the actions specified in step 5-E-<3> of Boeing All Operator Message M-7200-99-04035, dated May 21, 1999, are accomplished, the fuel tank in which the conduit has been replaced must be refueled prior to accomplishing step 6. \n\n\t(e)\tAccomplishment of the requirements of paragraph (c) of this AD is not required if the requirements of paragraph (i) of this AD are accomplished within the times specified in paragraph (a) or (b) of this AD, as applicable. \n\nNew Requirements of this AD: \n\n\t(f)\tFor airplanes with 50,000 or more total flight hours as of the effective date of this AD, within 20 days after the effective date of this AD, accomplish the requirements of paragraph (i) of this AD. \n\n\t(g)\tFor airplanes with less than 50,000 total flight hours, but more than 30,000 total flight hours, as of the effective date of this AD, within 30 days after the effective date of this AD, accomplish therequirements of paragraph (i) of this AD. \n\n\t(h)\tFor airplanes with 30,000 total flight hours or fewer, as of the effective date of this AD, within 90 days after the effective date of this AD, accomplish the requirements of paragraph (i) of this AD. \n\nDetailed Visual Inspection, Corrective Action, and Installation \n\n\t(i)\tPerform a detailed visual inspection of the in-tank fuel boost pump wire bundles, and applicable corrective actions; and, except as provided in paragraph (j) of this AD, install sleeving over the wire bundles; in accordance with Boeing Alert Service Bulletin 727-28A0126, dated May 24, 1999. \n\n\tNOTE 2: 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 mirrors, magnifying lenses, etc. may be used. Surface cleaning and elaborate access procedures may be required. \n\nInstallation: Possible Deferral \n\n\t(j)\tInstallation of sleeving over the wire bundles, as required by paragraph (i) of this AD, may be deferred if, within 18 months or 6,000 flight hours, whichever occurs first, after accomplishment of the inspection and applicable corrective actions required by paragraph (i), the following actions are accomplished: Perform a detailed visual inspection of the in-tank fuel boost pump wire bundles, and applicable corrective actions; and install sleeving over the wire bundles; in accordance with Boeing Alert Service Bulletin 727-28A0126, dated May 24, 1999. \n\nRepetitive Inspections and Corrective Actions \n\n\t(k)\tRepeat the detailed visual inspection and applicable corrective actions required by paragraphs (i) and (j) of this AD at intervals not to exceed 30,000 flight hours. \n\nAlternative Methods of Compliance \n\n\t(l)\tAn 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, Transport Airplane Directorate. 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. \n\n\tNOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. \n\nSpecial Flight Permits \n\n\t(m)\tSpecial 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. \n\nIncorporation by Reference \n\n\t(n)\tThe actions shall be done in accordance with Boeing All Operator Message (AOM) M-7200-99-04035, dated May 21, 1999, or Boeing Alert Service Bulletin 727-28A0126, dated May 24, 1999, as applicable. 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. \n\n\t(o)\tThis amendment becomes effective on June 28, 1999, to all persons except those persons to whom it was made immediately effective by telegraphic AD T99-12-52, issued on May 24, 1999, which contained the requirements of this amendment.

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Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of October 30, 2026. Connections as data: /graph/directive/99-12-52.json · aircraft systems.