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

[Federal Register Volume 64, Number 153 (Tuesday, August 10, 1999)]
[Proposed Rules]
[Pages 43316-43318]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-20503]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-71-AD]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain McDonnell Douglas MD-11 
and MD-11F series airplanes. This proposal would require 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 proposal also 
would require repetitive inspections of the repaired area; and a 
permanent modification of the wire harnesses if metallic transitions 
are not installed, which would terminate the repetitive inspections. 
This proposal is prompted by a report of chafing and damage to a wire 
harness of a tail tank fuel transfer pump. The actions specified by the 
proposed AD are intended 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.

DATES: Comments must be received by September 24, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-71-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056. Comments may be inspected at this location 
between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal 
holidays.
    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, 
Transport Airplane Directorate, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT: Roscoe Van Dyke, Aerospace Engineer, 
Propulsion Branch, ANM-140L, FAA, Transport Airplane Directorate, Los 
Angeles Aircraft Certification Office, 3960 Paramount Boulevard, 
Lakewood, California 90712-4137; telephone (562) 627-5254; 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 notice may be changed in 
light of the comments received.
    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 notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 99-NM-71-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. 99-NM-71-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received a report of chafing and damage to a wire 
harness of a tail tank fuel transfer pump on a McDonnell Douglas Model 
MD-11 series airplane. The cause of such chafing and damage has been 
attributed to wires chafing against a combination of wire mesh tape and 
braided shielding, which were installed during production as a 
substitute for metallic transitions at the wiring harness breakouts. 
Chafing or damage of a wire harness, if not corrected, could result in 
an inoperative fuel transfer pump and/or an increased risk of a fire or 
explosion from a fuel leak.

Explanation of Relevant Service Information

    The FAA has reviewed and approved McDonnell Douglas Alert Service 
Bulletin MD11-28A101, dated August 24, 1998, which describes procedures 
for a one-time visual inspection to determine if metallic transitions 
are installed on the wire harnesses of the tail tank fuel transfer 
pumps, and to determine if damaged wires are present; repair, if 
necessary; and repetitive inspections of the repaired area. The FAA 
also has reviewed and approved McDonnell Douglas Service Bulletin MD11-
28-102, Revision 01, dated June 23, 1999, which describes procedures 
for a permanent modification of the wire harnesses if metallic 
transitions are not installed. Accomplishment of the permanent 
modification would eliminate the need for the repetitive inspections in 
service bulletin MD11-28A101. Accomplishment of the actions specified 
in the service bulletins 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 bulletins described previously, except as discussed below.

Differences Between the Proposed Rule and the Relevant Service 
Information

    Operators should note that, although McDonnell Douglas Alert 
Service Bulletin MD11-28A101, dated August 24, 1998, recommends 
accomplishing the visual inspection within 15 days (after the release 
of the service bulletin), the FAA has determined that a compliance time 
of 30 days would be appropriate. In developing an appropriate 
compliance time for the

[[Page 43317]]

proposed visual inspection of this AD, the FAA considered not only the 
manufacturer's recommendation, but the degree of urgency associated 
with addressing the subject unsafe condition, the average utilization 
of the affected fleet, the time necessary to perform the inspection 
(less than five work hours), and reports from the manufacturer, which 
indicate that all affected airplanes have been inspected. In light of 
all of these factors, the FAA finds a 30-day compliance time for 
initiating the proposed visual inspection to be warranted, in that it 
represents an appropriate interval of time allowable for affected 
airplanes to continue to operate without compromising safety.
    Operators should note that the procedures described in condition 2 
of McDonnell Douglas Alert Service Bulletin MD11-28A101, dated August 
24, 1998, permit flight for 15 days before installation of a temporary 
repair, if metallic transitions are not installed on wire harnesses of 
the tail tank fuel transfer pumps. This proposed AD would require 
accomplishment of a temporary repair, prior to further flight. The FAA 
has determined that, because of the safety implications and 
consequences associated with chafing and damage of wires, any subject 
wire harness that is found to not have metallic transitions installed 
must be repaired prior to further flight.
    Operators should also note that, although McDonnell Douglas Service 
Bulletin MD11-28-102, Revision 01, dated June 23, 1999, recommends 
accomplishing the permanent modification at the earliest practical 
maintenance period (after the release of the service bulletin), the FAA 
has determined that a compliance time of 5 years would be appropriate. 
In developing an appropriate compliance time for the proposed 
modification of this AD, the FAA considered not only the manufacturer's 
recommendation, but the degree of urgency associated with addressing 
the subject unsafe condition, the average utilization of the affected 
fleet, and the time necessary to perform the modification (less than 
nine hours). In light of all of these factors, the FAA finds a 5-year 
compliance time for initiating the proposed modification to be 
warranted, in that it represents an appropriate interval of time 
allowable for affected airplanes to continue to operate without 
compromising safety.

Cost Impact

    There are approximately 14 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 5 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
1 work hour per airplane to accomplish the proposed inspection, and 
that the average labor rate is $60 per work hour. Based on these 
figures, the cost impact of the proposed AD on U.S. operators is 
estimated to be $300, or $60 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the requirements of this AD 
action, and that no operator would accomplish those actions in the 
future if this AD were not adopted. However, the FAA has been advised 
that manufacturer warranty remedies are available for labor costs 
associated with accomplishing the actions required by this proposed AD. 
Therefore, the future economic cost impact of this rule on U.S. 
operators may be less than the cost impact figure indicated above.

Regulatory Impact

    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    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.


Sec. 39.13  [Amended]

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

McDonnell Douglas: Docket 99-NM-71-AD.

    Applicability: Model MD-11 and MD-11F series airplanes, as 
listed in McDonnell Douglas Alert Service Bulletin MD11-28A101, 
dated August 24, 1998, 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 (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 prevent wire chafing and damage which could result in an 
inoperative tail tank fuel transfer pump and/or an increased risk of 
a fire or explosion from a fuel leak, accomplish the following:

Inspection and Corrective Actions

    (a) Within 30 days after the effective date of this AD, 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.
    (1) If all metallic transitions are installed, no further action 
is required by 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 the effective date of this AD, 
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 2: Modification of the wire harnesses accomplished prior to 
the effective date of this AD in accordance with McDonnell Douglas 
Service Bulletin MD11-28-102,

[[Page 43318]]

dated January 29, 1999, is considered acceptable for compliance with 
the modification required by paragraph (a)(2)(iii) of this AD.

Alternative Methods of Compliance

    (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 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, 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 Permits

    (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.
    Issued in Renton, Washington, on August 4, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-20503 Filed 8-9-99; 8:45 am]
BILLING CODE 4910-13-P