# AD 96-12-10: Airworthiness Directives; McDonnell Douglas Model MD-11 Series Airplanes - Type: Airworthiness directive - Effective: June 21, 1996 - Published: June 6, 1996, 61 FR 28736–28738 - Issued as: Final rule; request for comments - Superseded by: Nothing supersedes this AD - Amendment: 39-9652 - Docket: 96-NM-56-AD - Official PDF: https://openairdocs.org/files/sha256/fe/5e/fe5e0fc82e5a8aefcb48e1eed7ca50236c76bd4a8e3eb7b632987d9fd2cee74d (from https://www.govinfo.gov/content/pkg/FR-1996-06-06/pdf/96-14037.pdf) - Federal Register: https://www.federalregister.gov/documents/1996/06/06/96-14037/airworthiness-directives-mcdonnell-douglas-model-md-11-series-airplanes - Page: https://openairdocs.org/ad/96-12-10 ## Summary This amendment adopts a new airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model MD-11 series airplanes. This action requires either the application of a vapor sealant on the back of the receptacle of the auxiliary power unit (APU) power feeder cable; or a visual inspection for gold-plating and evidence of damage of the connector contacts of the power feeder cable of the APU generator, and various follow-on actions. This amendment is prompted by reports of burning and arcing of these connector contacts. The actions specified in this AD are intended to reduce the potential for a fire hazard as a result of such burning or arcing. ## The airworthiness directive ### PART 39--AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. ### Sec. 39.13 [Amended] 2. Section 39.13 is amended by adding the following new airworthiness directive: 96-12-10 McDonnell Douglas: Amendment 39-9652. Docket 96-NM-56-AD. Applicability: Model MD-11 series airplanes; as listed McDonnell Douglas Alert Service Bulletin MD11-24A104, dated May 7, 1996; certificated in any category. Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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 (b) 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. Compliance: Required as indicated, unless accomplished previously. To reduce the potential for a fire hazard as a result of burning and arcing of the connector contacts of the power feeder cable of the auxiliary power unit (APU) generator, accomplish the following: ### (a) (a) Within 60 days after the effective date of this AD, accomplish the actions specified in either paragraph (a)(1) or (a)(2) of this AD: (1) Apply a vapor sealant on the back of the APU power feeder cable receptacle in accordance with McDonnell Douglas Alert Service Bulletin MD11-24A104, dated May 7, 1996. Or (2) Accomplish the actions specified in both paragraph (a)(2)(i) and (a)(2)(ii) of this AD in accordance with McDonnell Douglas Alert Service Bulletin MD11-24A104, dated May 7, 1996. (i) Perform a one-time visual inspection for color (gold-plating) and evidence of damage of the connector contacts (pins/ sockets) of the power feeder cable of the APU generator located in the upper left corner of the APU compartment in the forward bulkhead; and (ii) Replace any damaged pin or socket with a gold-plated pin or socket, or deactivate the electrical operation of the APU until such replacement is accomplished. ### (b) (b) 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, Los Angeles ACO. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles ACO. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO. ### (c) (c) 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. ### (d) (d) The actions shall be done in accordance with McDonnell Douglas Alert Service Bulletin MD11-24A104, dated May 7, 1996. 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 McDonnell Douglas Corporation, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Technical Publications Business Administration, Department C1-L51 (2-60). Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. ### (e) (e) This amendment becomes effective on June 21, 1996. Issued in Renton, Washington, on May 30, 1996. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. ## Rule preamble ### Dates Effective June 21, 1996. The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of June 21, 1996. Comments for inclusion in the Rules Docket must be received on or before August 5, 1996. ### Addresses Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-103, Attention: Rules Docket No. 96-NM-56-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. The service information referenced in this AD may be obtained from McDonnell Douglas Corporation, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Technical Publications Business Administration, Department C1-L51 (2-60). This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. ### For further information contact Brett Portwood, Aerospace Engineer, Systems and Equipment Branch, ANM-130L, FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712; telephone (310) 627-5347; fax (310) 627-5210. ### Supplementary information The FAA has received several reports of burning and arcing of the connector contacts (pins/sockets) of the power feeder cable of the auxiliary power unit (APU) generator on Model MD-11 series airplanes. This condition was indicated by the inability to electrically power the airplane using APU generator power. In all cases, the connector and receptacle were heat-damaged beyond repair. The associated power feeder cables also sustained heat damage. Investigation revealed that the connector contacts had been nickel plated during production. These connector contacts must be gold plated to be able to withstand the loads applied. Burning and arcing of the connector contacts of the power feeder cable of the APU generator, if not corrected, could result in potential fire hazard. ### Explanation of Relevant Service Information The FAA has reviewed and approved McDonnell Douglas Alert Service Bulletin MD11-24A104, dated May 7, 1996, which describes procedures for application of a vapor sealant on the back of the receptacle of the APU power feeder cable. Applying the vapor sealant will reduce the possibility of fire or burning until the remainder of the actions specified in the alert service bulletin can be accomplished. The alert service bulletin also describes procedures for a one-time visual inspection for color (gold plating) and evidence of damage of the connector contacts (pins/sockets) of the power feeder cable of the APU generator located in the upper left corner of the APU compartment in the forward bulkhead. It also describes procedures for replacement of damaged pins and sockets with gold-plated pins and sockets, or deactivation of the electrical operation of the APU until such replacement is accomplished. The alert service bulletin specifies that the visual inspection and replacement or deactivation (if necessary) actions eliminate the need for applying a vapor sealant. Additionally, the alert service bulletin describes procedures for eventual replacement of undamaged pins and sockets that are nickel-plated or made of copper (brass), with gold-plated pins and sockets. ### Explanation of the Requirements of the Rule Since an unsafe condition has been identified that is likely to exist or develop on other Model MD-11 series airplanes of the same type design, this AD is being issued to reduce the potential for a fire hazard as a result of burning and arcing of the connector contacts of the power feeder cable of the APU generator. This AD requires either: 1. The application of a vapor sealant on the back of the receptacle of the APU power feeder cable; or 2. A one-time visual inspection for color (gold-plating) and evidence of damage of the connector contacts (pins/sockets) of the power feeder cable of the APU generator; and either replacement of damaged pins and sockets with gold-plated pins and sockets, or deactivation of the electrical operation of the APU until such replacement is accomplished. The actions are required to be accomplished in accordance with the alert service bulletin described previously. This AD is considered to be interim action. The FAA may consider further rulemaking action to require operators who install the vapor sealant to eventually accomplish the one-time visual inspection (and follow-on actions) and the replacement of nickel-plated or copper (brass) pins and sockets with gold-plated pins and sockets. However, the compliance time that the FAA is considering for accomplishment of those actions are sufficiently long so that prior notice and time for public comment will be practicable. ### Determination of Rule's Effective Date Since 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. ### Comments Invited Although 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. Comments 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. Commenters 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 96-NM-56-AD.'' The postcard will be date stamped and returned to the commenter. ### Regulatory Impact The 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. The 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. ### List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. ### Adoption of the Amendment Accordingly, 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: No proposed rule in this release led to it. Its text cites no advisory circulars or STCs. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.