[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
