Airworthiness Directives; McDonnell Douglas Model MD-11 and -11F Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain McDonnell Douglas Model MD-11 series airplanes, that currently requires an inspection to detect chafing or damage of the electrical wires leading to the terminal strips in the center accessory compartment (CAC) area, and corrective actions if necessary. That AD also currently requires revising the wire connection stack up of certain cable terminals at the electrical power center bays in the CAC, and replacing certain terminal strips with new strips and removing applicable nameplates at electrical power center bays. This action would require additional actions for improving the terminal strips and would revise the applicability of the existing AD to include additional airplanes. This proposal is prompted by issuance of revised service information. The actions specified by the proposed AD are intended to prevent arcing and sparking damage to the power feeder cables, terminal strips, and adjacent structure, and consequent smoke and fire in the CAC.

DATES:

Comments must be received by September 8, 2003.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-163-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 (425) 227-1232. Comments may also be sent via the Internet using the following address: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must contain “Docket No. 2001-NM-163-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: Data and Service Management, Dept. C1-L5A (D800-0024). This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

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 90712-4137; telephone (562) 627-5350; fax (562) 627-5210.

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 2001-NM-163-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. 2001-NM-163-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

On November 22, 2000, the FAA issued airworthiness directive (AD) 2000-24-12, amendment 39-12019 (65 FR 75615, December 4, 2000), applicable to certain McDonnell Douglas Model MD-11 series airplanes, to require an inspection to detect chafing or damage of the electrical wires leading to the terminal strips in the center accessory compartment (CAC) area, and corrective actions if necessary. That AD also requires revising the wire connection stack up of certain cable terminals at the electrical power center bays in the CAC, and replacing certain terminal strips with new strips and removing applicable nameplates at electrical power center bays. That action was prompted by an incident of arcing between a power feeder cable and terminal strip support bracket. The requirements of that AD are intended to prevent arcing and sparking damage to the power feeder cables, terminal strips, and adjacent structure, and consequent smoke and fire in the CAC.

Other Related Rulemaking

We, in conjunction with Boeing and operators of Model MD-11 and -11F airplanes, have reviewed 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 corrective actions identified during that process. We have previously issued several other ADs and may consider further rulemaking actions to address the remaining identified unsafe conditions.

Actions Since Issuance of Previous Rule

Since the issuance of AD 2000-24-12, we have reviewed and approved Revision 02 of Boeing Alert Service Bulletin MD11-24A097, including Evaluation Form, dated December 4, 2002 (the original issue of the service bulletin was referenced in AD 2000-24-12 as the appropriate source of service information for accomplishing the required actions). Revision 02 provides additional terminal strip information; adds airplanes to the effectivity; and corrects part numbers for the terminal stud stack up washers, which were inadvertently called out incorrectly in the original issue of this service bulletin. More work is necessary on all airplanes changed per the original issue and Revision 01 of the service bulletin.

For certain airplanes, Revision 02 of the service bulletin describes procedures for:

• Revising the wire connection stack up of the cable terminals at the electrical power center bays in the CAC, as applicable, and doing a one-time general visual inspection of the surrounding structure and electrical cables for chafing or damage;
• Replacing terminal strips, removing the applicable nameplate at the electrical power center bays 1, 2, and 3 in the CAC, and doing a general visual inspection of the surrounding structure and electrical cables for arcing damage.

For certain other airplanes, Revision 02 of the service bulletin also describes procedures for relocating the terminal strip, and doing a general visual inspection of the surrounding structure and electrical cables for arcing damage.

If any chafing or damage is detected during any general visual inspection, Revision 02 of the service bulletin describes procedures for repairing or replacing the damaged or chafed component with new or serviceable components.

Accomplishment of the actions specified in Revision 02 of the service bulletin is intended to adequately address the identified unsafe condition.

Explanation of Change to Applicability

The applicability of this notice of proposed rulemaking (NRPM) differs from AD 2000-24-12 in that it identifies model designations as published in the most recent type certificate data sheet for the affected models, and references Revision 02 of the service bulletin, which includes additional airplanes that are subject to 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 supersede AD 2000-24-12 to require accomplishment of the applicable actions specified in Revision 02 of the service bulletin described previously; except as discussed below.

Differences Between Proposed AD and Service Bulletin

Operators should note that Revision 02 of the service bulletin specifies to repair damage or chafed structure per the Structural Repair Manual (SRM). However, the SRM does not provide adequate procedures for repair of certain structural material. Therefore, this proposed AD would require the repair of damaged or chafed structure that is not covered in the SRM to be accomplished per a method approved by the FAA.

In addition, Revision 02 of the service bulletin specifies to use the form located in the Appendix for reporting inspection findings to the airplane manufacturer. Although the service bulletin references a reporting requirement, such reporting is not required by this AD. The airplane manufacturer has also informed us that it inadvertently published the service bulletin without the Appendix.

Changes to 14 CFR Part 39/Effect on the AD

On July 10, 2002, the FAA issued a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs the FAA's airworthiness directives system. The regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance (AMOCs). Because we have now included this material in part 39, only the office authorized to approve AMOCs is identified in each individual AD.

Cost Impact

There are approximately 163 Model MD-11 and -11F airplanes of the affected design in the worldwide fleet. The FAA estimates that 73 airplanes of U.S. registry would be affected by this proposed AD.

The new actions that are proposed in this AD action would take approximately between 1 and 7 work hours per airplane (depending on the airplane configuration) to accomplish, at an average labor rate of $65 per work hour. Required parts would cost approximately between $721 and $2,035 per airplane (depending on the airplane configuration). Based on these figures, the cost impact of the proposed requirements of this AD on U.S. operators is estimated to be between $786 and $2,490 per airplane (depending on the airplane configuration).

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the current or proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this 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.