AD 94-11-02

This amendment adopts a new airworthiness directive (AD) that is applicable to all Boeing Model 767 series airplanes. This action requires repetitive detailed visual and eddy current inspections to detect cracks of certain midspar fuse pins, and replacement of any cracked midspar fuse pin with a new fuse pin. This amendment is prompted by reports of longitudinal fatigue cracks on certain midspar fuse pins installed on Boeing Model 767 series airplanes. The actions specified in this AD are intended to prevent loss of the strut and engine due to cracking of both fuse pins on the same strut.

Final rule; request for comments

94-11-02 BOEING: Amendment 39-8918. Docket 94-NM-60-AD. \n\n\tApplicability: All Model 767 series airplanes, certificated in any category. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent cracking of both fuse pins on the same strut, which could result in loss of the strut and engine, accomplish the following: \n\n\t(a)\tFor airplanes having midspar fuse pins, part number 311T3102-1: Perform a detailed visual inspection and an eddy current inspection to detect cracks of the midspar fuse pins, in accordance with Boeing Alert Service Bulletin 767-54A0062, dated April 14, 1994, at the time specified in paragraph (a)(1), (a)(2), (a)(3), or (a)(4) of this AD, as applicable. Repeat these inspections thereafter at intervals not to exceed 3,000 landings. \n\n\t\t(1)\tFor airplanes having midspar fuse pins that have accumulated 18,000 or more total landings as of the effective date of this AD, accomplish the inspections within 60 days after the effective date of this AD.\n \n\t\t(2)\tFor airplanes having midspar fuse pins that have accumulated 15,000 or more total landings, but less than 18,000 total landings, as of the effective date of this AD, accomplish the inspections within 90 days after the effective date of this AD. \n\n\t\t(3)\tFor airplanes having midspar fuse pins that have accumulated 10,000 or more total landings, but less than 15,000 total landings, as of the effective date of this AD, accomplish the inspections within 120 days after the effective date of this AD. \n\n\t\t(4)\tFor airplanes having midspar fuse pins that have accumulated less than 10,000 total landings as of the effective date of this AD, accomplish the inspections prior to the accumulation of 10,000 total landings on the fuse pin, or within 120 days after the effective date of this AD, whichever occurs later. \n\n\t(b)\tFor airplanes having a midspar fuse pin, part number 311T3102-2 or 311T2102-1: Prior to the accumulation of 15,000 total landings on the fuse pin,or within 90 days after the effective date of this AD, whichever occurs later, perform a detailed visual inspection and an eddy current inspection to detect cracks on the midspar fuse pins, in accordance with Boeing Alert Service Bulletin 767-54A0062, dated April 14, 1994. Repeat these inspections thereafter at intervals not to exceed 3,000 landings. \n\n\t(c)\tIf any crack is found during an inspection required by paragraph (a) or (b) of this AD, prior to further flight, replace the cracked midspar fuse pin with a new fuse pin, in accordance with Boeing Alert Service Bulletin 767-54A0062, dated April 14, 1994. Thereafter, perform the detailed visual and eddy current inspections specified in paragraph (a) or (b) of this AD, as applicable, on the new fuse pin at the time specified in paragraph (c)(1) or (c)(2) of this AD. \n\n\t\t(1)\tFor airplanes having midspar fuse pins, part number 311T3102-1: Perform the initial inspection of the new fuse pin prior to the accumulation of 10,000 total landings on the new fuse pin. Repeat the inspection thereafter at intervals not to exceed 3,000 landings. \n\n\t\t(2)\tFor airplanes having midspar fuse pins, part numbers 311T3102-2 and 311T2102-1: Perform the initial inspection of the new fuse pin prior to the accumulation of 15,000 total landings on the new fuse pin. Repeat the inspection thereafter at intervals not to exceed 3,000 landings. \n\n\t(d)\tWhen any fuse pin is removed from a strut equipped with a General Electric engine, the engine must be removed in accordance with procedures described in the Boeing 767 Maintenance Manual, subject 71-00-02; or supported in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. \n\n\t(e)\tWhen any fuse pin is removed from a strut equipped with a Pratt & Whitney engine, the engine must be removed in accordance with procedures described in the Boeing 767 Maintenance Manual, subject 71-00-02; or supported in accordance with procedures described in the Boeing 767 Maintenance Manual, subject 54-51-02, Temporary Revisions (TR), dated April 22, 1994; or supported in accordance with a method approved by the Manager, Seattle ACO, FAA, Transport Airplane Directorate. \n\n\t(f)\tWhen any fuse pin is removed from a strut equipped with a Rolls-Royce engine, the engine must be removed in accordance with procedures described in the Boeing 767 Maintenance Manual, subject 71-00-02; or supported in accordance with procedures described in the Boeing 767 Maintenance Manual, subject 54-51-02; or supported in accordance with a method approved by the Manager, Seattle ACO, FAA, Transport Airplane Directorate. \n\n\t(g)\tAny midspar fuse pin, part number 311T3102-1, 311T3102-2, or 311T2102-1, that has been removed from the strut and inspected for cracks using the 100 percent magnetic particle inspection technique described in Boeing Alert Service Bulletin 767-54A0062, dated April 14, 1994, may be reinstalled on the strutprovided that the fuse pin is found to be crack-free during the magnetic particle inspection. Prior to the accumulation of 3,000 total landings after reinstallation of the fuse pin, the fuse pin must be inspected in accordance with the requirements of paragraph (a) or (b) of this AD, as applicable. \n\n\t(h)\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(i)\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(j)\tThe inspections and replacement shall be done in accordance with Boeing Alert Service Bulletin 767-54A0062, dated April 14, 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(k)\tThis amendment becomes effective on June 10, 1994.

The FAA has received several reports of longitudinal fatigue cracks on certain midspar fuse pins installed on Boeing Model 767 series airplanes. A total of five cracked fuse pins have been found on two airplanes that had accumulated between 15,628 and 23,056 total landings. Cracks were found on both midspar fuse pins of the same strut on one of these airplanes. A possible cause of this cracking is ovalization of the fuse pin due to stress. Results of testing of fuse pins having a design similar to those that cracked have revealed no significant reduction in shear strength with longitudinal cracks up to one inch in length. Cracking of both fuse pins on the same strut, if not corrected, could result in loss of the strut and engine. \n\n\tAll reported cracks have occurred on midspar fuse pins having part number 311T3102-1. Midspar fuse pins having part numbers 311T3102-2 and 311T2102-1 are similar in design to the fuse pins on which cracking was found and,therefore, also are subject to the addressed unsafe condition. \n\n\tThe FAA has reviewed and approved Boeing Alert Service Bulletin 767-54A0062, dated April 14, 1994, that describes procedures for repetitive detailed visual and eddy current inspections to detect cracks of certain midspar fuse pins, and replacement of any cracked midspar fuse pin with a new fuse pin. Accomplishment of these inspections will provide early detection of cracks in the midspar fuse pins of both struts. \n\n\tSince an unsafe condition has been identified that is likely to exist or develop on other Model 767 series airplanes of the same type design, this AD is being issued to prevent cracking of both fuse pins on the same strut, which could result in loss of the strut and engine. This AD requires repetitive detailed visual and eddy current inspections to detect cracks of certain midspar fuse pins, and replacement of any cracked midspar fuse pin with a new fuse pin. The actions are required to be accomplishedin accordance with the alert service bulletin described previously. \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 that good 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 on the 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-60-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\n\n2.\tSection 39.13 is amended by adding the following new airworthiness directive: