01-4057. Airworthiness Directives; McDonnell Douglas Model MD-11 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model MD-11 series airplanes. This proposal would require an inspection to detect arcing damage of the electrical cables leading to the terminal strips and surrounding structure in the wing areas inboard of the pylons 1 and 3 and the No. 2 engine; and corrective actions, if necessary. This proposal also would require revising the cable connection stackup of the terminal strips on the wings and No. 2 engine. This action is necessary to prevent arcing damage to the terminal strips and damage to the adjacent structure in the wing areas inboard of the pylons 1 and 3 and the No. 2 engine, which could result in a fire inboard of the pylons 1 and 3 or the No. 2 engine. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by April 6, 2001.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2000-NM-192-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2000-NM-192-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 for Windows or ASCII text.

The service information referenced in the proposed rule may be obtained from Boeing Commercial Aircraft Group, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Technical Publications Business Administration, Dept. 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, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT:

Brett Portwood, Aerospace Engineer, Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed 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 above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this action may be changed in light of the comments received.

Submit comments using the following format:

• Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
• For each issue, state what specific change to the proposed AD is being requested.
• Include justification (e.g., reasons or data) for each request.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2000-NM-192-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2000-NM-192-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

As part of its practice of re-examining all aspects of the service experience of a particular aircraft whenever an accident occurs, the FAA has become aware of an incident in which arcing occurred between the power feeder cables and support bracket of the terminal strips on a McDonnell Douglas Model MD-11 series airplane. Investigation revealed that inadequate clearance exists between the terminal strips and support brackets of the wing areas inboard of the pylons 1 and 3 and the No. 2 engine. This condition, if not corrected, could result in arcing damage to the terminal strips and damage to the adjacent structure of the wing areas inboard of the pylons 1 and 3 and the No. 2 engine, which could result in a fire inboard of the pylons 1 and 3 or the No. 2 engine.

Other Related Rulemaking

The FAA, in conjunction with Boeing and operators of Model MD-11 series airplanes, is continuing to review all aspects of the service history of those airplanes to identify potential unsafe conditions and to take appropriate corrective actions. This proposed AD is one of a series of actions identified during that process. The process is continuing and the FAA may consider additional rulemaking actions as further results of the review become available.

Explanation of Relevant Service Information

The FAA has reviewed and approved McDonnell Douglas Alert Service Bulletin MD11-24A187, dated October 4, 2000, which describes procedures for a general visual inspection to detect arcing damage of the electrical cables leading to the terminal strip and the surrounding structure in the wing areas inboard of the pylons 1 and 3 and the No. 2 engine; and corrective actions, if necessary. The corrective actions include replacing any damaged terminal strip with a like part and sealing the screw heads of any replaced terminal strip; repairing any arcing or structure damage; and replacing any damaged cable with a new cable. The service bulletin also describes procedures for revising the cable connection stackup of the terminal strips on the left and right wings and the No. 2 engine (including performing a general visual inspection for damaged cable assemblies; repairing of any damaged cable assembly; and tightening terminal lug hardware). Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the actions specified in the service bulletin described previously; except as discussed below.

Differences Between Proposed Rule and Service Bulletin

Operators should note that the service bulletin specifies to repair damaged structure per the Structural Repair Manual (SRM). However, the SRM does not provide adequate procedures for repair of certain structural material. Therefore, this proposal would require the repair of damaged structure that is not covered in the SRM to be accomplished per a method approved by the FAA.

Cost Impact

There are approximately 153 Model MD-11 series airplanes of the affected design in the worldwide fleet. The FAA estimates that 57 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 5 work hours per airplane to accomplish the proposed actions, and that the average labor rate is $60 per work hour. Required parts would cost approximately $60 per airplane. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $20,520, or $360 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this proposed AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

Regulatory Impact

The regulations proposed herein would not have a substantial direct effect 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, it is determined that this proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this proposed regulation (1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

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.

§ 39.13

[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

McDonnell Douglas: Docket 2000-NM-192-AD.

Applicability: Model MD-11 series airplanes, as listed in McDonnell Douglas Alert Service Bulletin MD-1124A187, dated October 4, 2000; certificated in any category.

Note 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 (c) 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 prevent arcing damage to the terminal strips and damage to the adjacent structure in the wing areas inboard of the pylons 1 and 3 and the No. 2 engine, which could result in a fire inboard of the pylons 1 and 3 or the No. 2 engine, accomplish the following:

Inspection and Corrective Actions, If Necessary

(a) Within 18 months after the effective date of this AD, do a general visual inspection to detect arcing damage of the electrical cables leading to the terminal strips and the surrounding structure in the wing areas inboard of the pylons 1 and 3 and the No. 2 engine, per McDonnell Douglas Alert Service Bulletin MD11-24A187, dated October 4, 2000.

Note 2:

For the purposes of this AD, a general visual inspection is defined as “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or drop-light, and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”

(1) If no arcing or structure damage is detected during the general visual inspection, before further flight, do the action specified in paragraph (b) of this AD.

(2) If any arcing damage is detected on any terminal strip, before further flight, replace the damaged terminal strip with a like part, and seal the screw heads of any replaced terminal strip, per the service bulletin.

(3) If any arcing damage is detected on any cable and the damage is within the limits specified in the service bulletin, before further flight, repair the arcing per the service bulletin, and do the action specified in paragraph (b) of this AD.

(4) If any arcing damage is detected on any cable and the damage is beyond the limits specified in the service bulletin, before further flight, replace the damaged cable with a new cable, per the service bulletin, and do the action specified in paragraph (b) of this AD.

(5) If any structure damage is detected, before further flight, do the actions specified in paragraphs (a)(5)(i) and (a)(5)(ii) of this AD.

(i) Repair the damaged structure per the service bulletin, except if the type of structural material that has been affected is not covered in the SRM, repair per a method approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA.

(ii) Do the action specified in paragraph (b) of this AD.

Follow-On Revision of the Cable Connection Stackup

(b) Revise the cable connection stackup of the terminal strips on the left and right wings and the No. 2 engine (including performing a general visual inspection for damaged cable assemblies; repairing of any damaged cable assembly; and tightening terminal lug hardware), per paragraph 3.B.4. of the Acomplishment Instructions of McDonnell Douglas Alert Service Bulletin MD11-24A187, October 4, 2000.

Alternative Methods of Compliance

(c) 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, FAA. 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 3:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO.

Special Flight Permit

(d) 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.

Issued in Renton, Washington, on February 12, 2001.

Vi L. Lipski,

Manager, Transport Airplane Directorate, Aircraft Certification Service.