E9-22580. Airworthiness Directives; McDonnell Douglas Model MD-11 and MD-11F Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) that applies to certain McDonnell Douglas Model MD-11 and MD-11F airplanes. The existing AD currently requires a one-time inspection to determine if metallic transitions are installed on wire harnesses of the tail tank fuel transfer pumps, and to determine if damaged wires are present; and repair, if necessary. This proposed AD would require modifying the case grounding for the alternate fuel pump of the tail tank, the leak detection thermal switch grounding for the number 2 engine, and wire braid grounding in the empennage and number 2 engine inlet. This proposed AD would also remove one airplane from the applicability of the existing AD. This proposed AD results from reports that the wire assembly for the alternate fuel pump is missing a case ground wire, and the lightning protection wire braid for wire assemblies located in the empennage and number 2 engine inlet are grounded improperly. We are proposing this AD to prevent insufficient grounding of the fuel pump, which in combination with an electrical failure within the fuel pump and a compromised electrical bond could cause a fuel tank ignition, resulting in consequent fire or explosion.

DATES:

We must receive comments on this proposed AD by November 2, 2009.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, 3855 Lakewood Boulevard, MC D800-0019, Long Beach, California 90846-0001; telephone [phone], extension 2; fax [phone]; e-mail [e-mail]; Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221 or 425-227-1152.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Samuel Lee, Aerospace Engineer, Propulsion Branch, ANM-140L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2009-0866; Directorate Identifier 2009-NM-074-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

On December 2, 1999, we issued AD 99-25-14, amendment 39-11457 (64 FR 69389, December 13, 1999), for certain McDonnell Douglas Model MD-11 and MD-11F airplanes. That AD requires a one-time inspection to determine if metallic transitions are installed on wire harnesses of the tail tank fuel transfer pumps, and to determine if damaged wires are present; and repair, if necessary. That AD also requires repetitive inspections of the repaired area; and a permanent modification of the wire harnesses if metallic transitions are not installed, which terminates the repetitive inspections. That AD resulted from a report of chafing and damage to a wire harness of a tail tank fuel transfer pump. We issued that AD to prevent wire chafing and damage, which could result in an inoperative fuel transfer pump and/or an increased risk of a fire or explosion from a fuel leak.

Actions Since Existing AD Was Issued

Since we issued AD 99-25-14, we have received reports that the wire assembly for the alternate fuel pump is missing a case ground wire, and the lightning protection wire braid for wire assemblies located in the empennage and number 2 engine inlet are grounded improperly. Further investigation revealed that the wiring of the anti-ice leak detection thermal switch of the number 2 engine was not included in the wire assembly, and that the support bracket of the leak detection thermal switch was not electrically bonded to the engine spar of the number 2 engine. Insufficient grounding of the fuel pump, in combination with an electrical failure within the fuel pump and a compromised electrical bond, could cause a fuel tank ignition, resulting in consequent fire or explosion.

Relevant Service Information

We have reviewed Boeing Alert Service Bulletin MD11-28A140, dated November 6, 2008. The service bulletin describes procedures to modify the case grounding for the alternate fuel pump of the tail tank and the leak detection thermal switch grounding for the number 2 engine. The modification also includes modifying the wire metal braid grounding in the empennage and the inlet of the number 2 engine, and testing the leak detection thermal switch for correct operation.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to develop on other airplanes of the same type design. For this reason, we are proposing this AD, which would supersede AD 99-25-14 and would retain the requirements of the existing AD. This proposed AD would also require accomplishing the actions specified in the “Relevant Service Information” described previously.

Changes to Existing AD

This proposed AD would retain all requirements of AD 99-25-14. Since AD 99-25-14 was issued, the AD format has been revised, and certain paragraphs have been rearranged. As a result, the corresponding paragraph identifiers have changed in this proposed AD, as listed in the following table:

Revised Paragraph Identifiers

Requirement in AD 99-25-14	Corresponding requirement in this proposed AD
Paragraph (a)	paragraph (g).

In addition, we have revised the applicability of AD 99-25-14 by referring to Boeing Alert Service Bulletin MD11-28A140, dated November 6, 2008, in paragraph (c) of this AD. This proposed AD would remove one airplane, fuselage number 450, from the applicability due to hull loss.

Costs of Compliance

There are about 13 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs for U.S. operators to comply with this proposed AD.

Estimated Costs

Action	Work hours	Average labor rate per hour	Parts	Cost per airplane	Number of U.S.-registered airplanes	Fleet cost
Inspection (required by AD 99-25-14)	1	$80	$80	$80, per inspection cycle	9	$720, per inspection cycle.
Modification (new proposed action)	16	80	1,248	$2,528	9	$22,752.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD 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.

For the reasons discussed above, I certify that the 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. 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.

We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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. The FAA amends § 39.13 by removing amendment 39-11457 (64 FR 69389, December 13, 1999) and adding the following new AD:

McDonnell Douglas: Docket No. FAA-2009-0866; Directorate Identifier 2009-NM-074-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by November 2, 2009.

Affected ADs

(b) This AD supersedes AD 99-25-14.

Applicability

(c) This AD applies to McDonnell Douglas Model MD-11 and MD-11F airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin MD11-28A140, dated November 6, 2008.

Subject

(d) Air Transport Association (ATA) of America Code 28: Fuel.

Unsafe Condition

(e) This AD results from reports that the wire assembly for the alternate fuel pump is missing a case ground wire, and the lightning protection wire braid for wire assemblies located in the empennage and number 2 engine inlet are grounded improperly. The Federal Aviation Administration is issuing this AD to prevent insufficient grounding of the fuel pump, which in combination with an electrical failure within the fuel pump and a compromised electrical bond could cause a fuel tank ignition, resulting in consequent fire or explosion.

Compliance

(f) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Restatement of Requirements of AD 99-25-14 With No Changes

Inspection and Corrective Actions

(g) Within 30 days after January 18, 2000 (the effective date of AD 99-25-14), perform a one-time visual inspection of the wire harnesses of the tail tank fuel transfer pumps to determine if metallic transitions are installed, and to determine if damaged wires are present, in accordance with McDonnell Douglas Alert Service Bulletin MD11-28A101, dated August 24, 1998 (“the service bulletin”).

(1) If all metallic transitions are installed, no further action is required by paragraph (g) of this AD.

(2) If metallic transitions are not installed, accomplish the following:

(i) Prior to further flight, accomplish the temporary repair in accordance with condition 2 of the service bulletin;

(ii) Repeat the visual inspection thereafter at intervals not to exceed 2 years; and

(iii) Within 5 years after January 18, 2000, permanently modify the wire harnesses in accordance with McDonnell Douglas Service Bulletin MD11-28-102, Revision 01, dated June 23, 1999. Accomplishment of this modification constitutes terminating action for the repetitive inspection requirements of this AD.

Note 1: Modification of the wire harnesses accomplished prior to January 18, 2000 (the effective date of AD 99-25-14), in accordance with McDonnell Douglas Service Bulletin MD11-28-102, dated January 29, 1999, is considered acceptable for compliance with the modification required by paragraph (g)(2)(iii) of this AD.

New Requirements of This AD

Modification

(h) Within 72 months after the effective date of this AD, modify the case grounding for the alternate fuel pump of the tail tank, the leak detection thermal switch grounding for the number 2 engine, and wire braid grounding in the empennage and number 2 engine inlet, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD11-28A140, dated November 6, 2008.

Alternative Methods of Compliance (AMOCs)

(i)(1) The Manager, Los Angeles Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Samuel Lee, Aerospace Engineer, Propulsion Branch, ANM-140L, FAA, Los Angeles ACO, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone [phone]; fax [phone].

(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD.

Issued in Renton, Washington, on September 11, 2009.

Stephen P. Boyd,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.