[Federal Register: February 1, 2000 (Volume 65, Number 21)]
[Proposed Rules]
[Page 4788-4790]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr01fe00-15]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 99-NM-267-AD]
RIN 2120-AA64
Airworthiness Directives; McDonnell Douglas Model 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 Model
MD-11 and MD-11F series airplanes. This proposal would require a one-
time detailed visual inspection of the generator power feeder wires to
detect chafed or damage wires; repair, if necessary; and a modification
of the generator power feeder wire installation. This proposal is
prompted by reports of generator power feeder wire chafing on the
closeout rib of the wing leading edge at a certain station due to
insufficient clearance between the generator power feeder wires and the
closeout rib. The actions specified by the proposed AD are intended to
prevent chafed and burnt generator power feeder wires, which could
result in arcing damage to a certain closeout rib of the wing leading
edge and fire damage to the wing structure, and consequent reduced
structural integrity of the wing.
DATES: Comments must be received by March 17, 2000.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 99-NM-267-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: 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 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-267-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-267-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
[[Page 4789]]
Supplementary Information
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 instances of the generator power feeder wires
chafing on the closeout rib of the wing leading edge at station Xcw=130
on McDonnell Douglas Model MD-11 and MD-11F series airplanes. In one
case, the wire was found burnt with burn residue on the leading edge
closeout rib. In this instance, the opposite side of the wire
installation was inspected and was also found to be chafing on the
closeout rib. Investigation revealed that there is insufficient
clearance between the power feeder wires and the closeout rib. This
condition, if not corrected, could result in arcing damage to the
closeout rib of the wing leading edge at station Xcw=130 and fire
damage to the wing structure, and consequent reduced structural
integrity of the wing.
This incident is not considered to be related to an accident that
occurred off the coast of Nova Scotia involving a McDonnell Douglas
Model MD-11 series airplane. The cause of that accident is still under
investigation.
Other Related Rulemaking
The FAA, in conjunction with Boeing and operators of Model MD-11
and MD-11F 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
airworthiness directive (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 MD11-24A172, dated September 8, 1999, which describes
procedures for a one-time detailed visual inspection of the generator
power feeder wire installation to detect chafed or damage wires;
repair, if necessary; and modification of the power feeder wire
installation. The modification involves removal of existing power
feeder clamps from the mounting bracket at station Xcw =130.6409 and
reinstallation of clamps using a new spacer and attaching parts.
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, this
proposed AD would require accomplishment of the actions specified in
the service bulletin described previously.
Cost Impact
There are approximately 189 airplanes of the affected design in the
worldwide fleet. The FAA estimates that 66 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 actions 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
$3,960, or $60 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 AD were not adopted.
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.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
McDonnell Douglas: Docket 99-NM-267-AD.
Applicability: Model MD-11 and MD-11F series airplanes, as
listed in McDonnell Douglas Alert Service Bulletin MD11-24A172,
dated September 8, 1999; 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 chafed and burnt generator power feeder wires, which
could result in arcing damage to a certain closeout rib of the wing
leading edge and fire damage to the wing structure, and consequent
reduced structural integrity of the wing, accomplish the following:
Inspection; Repair, If Necessary; and Modification
(a) Within 6 months after the effective date of this AD, perform
a detailed visual inspection of the generator power feeder wires to
detect chafed or damaged wires, and modify the generator power
feeder wire installation in accordance with McDonnell Douglas Alert
Service Bulletin MD11-24A172, dated September 8, 1999. If any chafed
or damaged wire is found, prior to further flight, repair in
accordance with the service bulletin.
Note 2: For the purposes of this AD, a detailed visual
inspection is defined as: ``An intensive visual examination of a
specific structural area, system, installation, or assembly to
detect damage, failure, or irregularity. Available lighting is
normally supplemented with a direct source of good lighting at
intensity deemed appropriate by the inspector. Inspection aids such
as mirror, magnifying lenses, etc., may be used. Surface cleaning
and elaborate access procedures may be required.''
[[Page 4790]]
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 January 21, 2000.
Vi L. Lipski,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 00-2007 Filed 1-31-00; 8:45 am]
BILLING CODE 4910-13-U