AD 94-11-05

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Boeing Model 767-200 and 767-300 series airplanes. This action requires repetitive inspections of the pumping unit assembly on the override and jettison fuel boost pump assemblies to detect looseness of the screws that attach the inlet diffuser assembly to the pumping unit housing, and repair or replacement of the pumping unit assembly with a serviceable assembly, if necessary. For certain airplanes, this AD also provides for deactivation of the center wing fuel tank as an alternative to the repetitive inspections. This amendment is prompted by reports of failures of the override and jettison fuel pumps due to damage to impeller units and pumping unit housings caused by loose diffuser rings in the fuel pump assemblies of these airplanes. During dry fuel operation, a loose diffuser ring may cause metal-to-metal contact. The actions specified in this AD are intended to prevent the generation of sparks and a potential ignition source inside the fuel tank caused by metal-to-metal contact during dry fuel pump operation.

Final rule; request for comments

94-11-05 BOEING: Amendment 39-8921. Docket 94-NM-58-AD. \n\n\n\tApplicability: Model 767-200 and -300 series airplanes; line positions 001 through 473 inclusive, 475 through 504 inclusive, 506 through 532 inclusive, and 534; certificated in any category. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent the generation of sparks and a potential ignition source inside the fuel tank, accomplish the following: \n\n\t(a)\tWithin 30 days after the effective date of this AD, accomplish either paragraph (a)(1) or (a)(2) of this AD, as applicable. \n\n\t\t(1)\tPerform an inspection of the pumping unit assembly, part number 5006286 series, on the override and jettison fuel boost pump assemblies to detect looseness of the screws that attach the inlet diffuser assembly to the pumping unit housing, in accordance with Boeing Alert Service Bulletin 767-28A0045, Revision 1, dated April 28, 1994. \n\n\t\t\t(i)\tIf no looseness is found, prior to further flight, identify the pumping unit assembly with "28-A5" next to the part number in the part number block or other blank space of the identification plate. Repeat the inspection thereafter at intervals not to exceed 1,000 hours time-in-service. \n\n\t\t\t(ii)\tIf any looseness is found, prior to further flight, accomplish either paragraph (a)(1)(ii)(A) or (a)(1)(ii)(B) of this AD; and repeat the inspection thereafter at intervals not to exceed 1,000 hours time-in-service. \n\n\t\t\t\t(A)\tReplace the pumping unit assembly with a serviceable assembly, in accordance with Boeing Alert Service Bulletin 767-28A0045, Revision 1, dated April 28, 1994. Or \n\n\t(B)\tRepair the pumping unit assembly in accordance with Sundstrand Alert Service Bulletin 5006286-28-A5, Revision 2, dated May 3, 1994. \n\n\t\t(2)\tFor airplanes having a center tank scavenge system: In lieu of accomplishing the inspection required by paragraph (a)(1) of this AD, the center wing fuel tank may be deactivated in accordance with Boeing Alert Service Bulletin 767-28A0045, Revision 1, dated April 28, 1994. The tank may be reactivated only after accomplishment of the inspection required by paragraph (a)(1) of this AD, and the repair or replacement, as necessary, required by paragraphs (a)(1)(ii)(A) and (a)(1)(ii)(B) of this AD. \n\n\t(b)\tWithin 10 days after accomplishing the initial inspection required by paragraph (a) of this AD, submit a report of inspection findings to the Manager, FAA, Transport Airplane Directorate, Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue, SW., Renton, Washington 98055-4056; fax (206) 227-1181. The report must include the inspection results, the airplane line position, the location of the pump on the airplane, and the number of hours time-in- service on the pumping unit assembly since new or since its last removal. Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056. \n\n\t(c)\tAs of 30 days after the effective date of this AD, no person shall install an override fuel boost pump assembly, part number 5006283 series, or an override/jettison fuel boost pump assembly, part number 5009656 series, on any airplane unless that assembly has been inspected and identified previously in accordance with Boeing Alert Service Bulletin 767-28A0045, Revision 1, dated April 28, 1994. \n\n\t(d)\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 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\nNOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any,may be obtained from the Seattle ACO. \n\n\t(e)\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 \n\t(f)\tThe actions shall be done in accordance with Boeing Alert Service Bulletin 767- 28A0045, Revision 1, dated April 28, 1994; and Sundstrand Alert Service Bulletin 5006286-28-A5, Revision 2, dated May 3, 1994. 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(g)\tThis amendment becomes effective on June 15, 1994.

The FAA has received reports of failures of the override and jettison fuel pumps on certain Boeing Model 767-200 and -300 series airplanes. Investigation revealed that the screws that attach the inlet diffuser assembly to the pumping unit housing became loose and were ingested into the fuel pump assembly. Loose screws caused the diffuser ring to become loose and contact the impeller, which damaged the impeller and pumping unit housing and caused the fuel pump to seize. During dry fuel pump operation, a loose diffuser ring also could cause metal-to-metal contact. This condition, if not corrected, could result in the generation of sparks and a potential ignition source inside the fuel tank. \n\n\tThe FAA has reviewed and approved Boeing Alert Service Bulletin 767-28A0045, Revision 1, dated April 28, 1994, that describes procedures for repetitive inspections of the pumping unit assembly on the override and jettison fuel boost pump assemblies to detect looseness of the screws that attach the inlet diffuser assembly to the pumping unit housing, and replacement of the pumping unit assembly with a serviceable assembly, if necessary. As an alternative to the inspections, the alert service bulletin also describes procedures for deactivating the center wing fuel tank. Accomplishment of either of these actions will prevent the inlet diffuser assembly and various parts in the pump assembly from creating an ignition source during dry fuel pump operation. \n\n\tIn addition, the FAA has reviewed and approved Sundstrand Alert Service Bulletin 5006286-28-A5, Revision 2, dated May 3, 1994, which describes procedures for repair of the pumping unit assembly. \n\n\tSince an unsafe condition has been identified that is likely to exist or develop on other Model 767-200 and -300 series airplanes of the same type design, this AD is being issued to prevent the generation of sparks and a potential ignition source inside the fuel tank. This AD requires repetitive inspections of the pumping unit assembly on the override and jettison fuel boost pump assemblies to detect looseness of the screws that attach the inlet diffuser assembly to the pumping unit housing, and repair or replacement of the pumping unit assembly with a serviceable assembly, if necessary. For certain airplanes, this AD also provides for deactivation of the center wing fuel tank as an alternative for the repetitive inspections. The inspections, replacement, and deactivation are required to be accomplished in accordance with the Boeing alert service bulletin described previously. The repair is required to be accomplished in accordance with the Sundstrand alert service bulletin described previously. \n\n\tThis AD also requires that operators submit a report of inspection findings to the FAA. \n\n\tSince a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and thatgood cause exists for making this amendment effective in less than 30 days. \n\n\tComments Invited \n\n\tAlthough this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified under the caption "ADDRESSES." All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed. \n\n\tComments are specifically invited onthe overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket. \n\n\tCommenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 94-NM-58-AD." The postcard will be date stamped and returned to the commenter. \n\n\tThe regulations adopted herein will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. \n\n\tThe FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES." \n\nList of Subjects in 14 CFR Part 39 \n\nAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment\n\nAccordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends 14 CFR part 39 of the Federal Aviation Regulations as follows: \n\nPART 39 - AIRWORTHINESS DIRECTIVES \n\n1.\tThe authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89. § 39.13 - (Amended) \n\n2.\tSection 39.13 is amended by adding the following new airworthiness directive: