AD 95-21-05

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Boeing Model 767 series airplanes. This action requires an inspection to detect damage of the wire bundles in the left side of the flight compartment in the vicinity of the stowage box for the captain's oxygen mask, and repair, if necessary; a continuity check on repaired wires; installation of sleeving over the wire bundles; and rerouting of the wire bundles. This amendment is prompted by reports of chafed wiring and minimal clearance between the oxygen connector and the adjacent wire bundles in the vicinity of the stowage box for the captain's oxygen mask. The actions specified in this AD are intended to prevent such chafing and inadequate clearance, which could result in electrical arcing and consequent oxygen leakage in the vicinity of the stowage box; these conditions, if not corrected, could result in a fire in the flight compartment.

Final rule; request for comments.

95-21-05 BOEING: Amendment 39-9390. Docket 95-NM-169-AD. \n\n\tApplicability: Model 767 series airplanes; line positions 2 through 589 inclusive except VA801 through VA810 inclusive, VN684 through VN691 inclusive, and VW701; 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 use the authority provided in paragraph (b) of this AD to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition; or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any airplane from the applicability of this AD. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent wire chafing and subsequent electrical arcing in the vicinity of the stowage box for the captain's oxygen mask, which could result in a fire in the flight compartment, accomplish the following:\n \n\t(a)\tWithin 45 days after the effective date of this AD, inspect to detect damage of the wire bundles in the left side of the flight compartment in the vicinity of the stowage box for the captain's oxygen mask, in accordance with Boeing Alert Service Bulletin 767-35A0028, dated September 7, 1995. \n\n\t\t(1)\tIf no damage is detected, prior to further flight, install protective sleeving on the wiring, and reroute the wire bundles, in accordance with the alert service bulletin.\n \n\t\t(2)\tIf any damage is detected, prior to further flight,accomplish the requirements of paragraphs (a)(2)(i) and (a)(2)(ii) of this AD. \n\n\t\t\t(i)\tRepair the wiring and perform a continuity check on each repaired wire, in accordance with the alert service bulletin. And \n\n\t\t\t(ii)\tInstall protective sleeving on the wiring and reroute the wire bundles, in accordance with the alert service bulletin. \n\n\t(b)\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 2: 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(c)\tSpecial flight permits may be issued in accordance with sections 21.197 and21.199 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(d)\tThe actions shall be done in accordance with Boeing Alert Service Bulletin 767- 35A0028, dated September 7, 1995. 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(e)\tThis amendment becomes effective on October 26, 1995.

The FAA has received a report indicating that a "MAP RANGE DISAGREE" message occurred on the left electronic horizontal situation indicator (EHSI) of a Boeing Model 767 series airplane. Investigation revealed that a wire in the vicinity of the stowage box for the captain's oxygen mask was chafed. Other wires were exposed and were in contact with the oxygen line fitting. This condition could result in a small hole in the oxygen line fitting, which may allow oxygen leakage. The FAA also received a report indicating that an operator found evidence of wire insulation wear in the area where the oxygen line fitting touched the wire bundle on one airplane. This operator also reported that three other airplanes had minimal clearance between the oxygen connector and the adjacent wire bundles. Chafing of the wires on oxygen system components in the vicinity of the stowage box for the captain's oxygen mask, if not corrected, could result in electrical arcing and leakage of oxygen; these conditions could result in a fire in the flight compartment. \n\n\tThe FAA has reviewed and approved Boeing Alert Service Bulletin 767-35A0028, dated September 7, 1995, which describes procedures for a one-time inspection to detect damage of the wire bundles in the left side of the flight compartment in the vicinity of the stowage box for the captain's oxygen mask and repair, if necessary; a continuity check on repaired wires; installation of sleeving over the wire bundles; and rerouting of the wire bundles. Accomplishment of these procedures will prevent chafing of these wires, which could result in electrical arcing, and will also ensure that adequate spacing separates the oxygen equipment and adjacent wire bundles. \n\tSince an unsafe condition has been identified that is likely to exist or develop on other Boeing Model 767 series airplanes of the same type design, this AD is being issued to prevent wire chafing on oxygen system components and consequent oxygen leakage in the vicinity of the stowage box for the captain's oxygen mask, which could result in a fire in the flight compartment. This AD requires a one-time inspection to detect damage of the wire bundles in the left side of the flight compartment in the vicinity of the stowage box for the captain's oxygen mask, and repair, if necessary; a continuity check on repaired wires; installation of sleeving over the wire bundles; and rerouting of the wire bundles. The actions are required to be accomplished in accordance with the alert service bulletin described previously. \n\n\tThis is considered to be interim action until final action is identified, at which time the FAA may consider further rulemaking. \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\nComments InvitedAlthough 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 suggesta 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 rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 95-NM-169-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 that it 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\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \nAdoption of the Amendment \n\tAccordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows: \n\nPART 39 - AIRWORTHINESS DIRECTIVES \n\t1. The authority citation for part 39 continues to read as follows: Authority: 49 USC 106(g), 40101, 40113, 44701. § 39.13 - (Amended) \n\t2. Section 39.13 is amended by adding the following new airworthiness directive: