[Federal Register Volume 66, Number 55 (Wednesday, March 21, 2001)]
[Proposed Rules]
[Pages 15817-15820]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-6941]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-410-AD]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model DC-10-10, -15, 
-30, and -30F (KC-10A Military) Series Airplanes, and Model MD-10-10F 
and -30F Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to certain McDonnell Douglas 
Model DC-10-10, -15, -30, and -30F (KC-10A military) series airplanes, 
and Model MD-10-10F and -30F series airplanes, that currently requires 
repetitive inspections to determine the condition of the lockwires on 
the forward engine mount bolts and correction of any discrepancies 
found. That AD also provides for optional terminating actions for the 
repetitive inspections. This action would require accomplishment of the 
previously optional terminating actions. This proposal is prompted by a 
report of discrepant forward engine mount bolts at the number 3 engine. 
The actions specified by the proposed AD are intended to prevent broken 
lockwires, which could result in loosening of the engine mount bolts, 
and consequent separation of the engine from the airplane.

DATES: Comments must be received by May 7, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-410-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: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2000-NM-410-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: 
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.

FOR FURTHER INFORMATION CONTACT: Ron Atmur, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; 
telephone (562) 627-5224; 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

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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 2000-NM-410-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. 2000-NM-410-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On September 29, 1999, the FAA issued AD 95-04-07 R2, amendment 39-
11354 (64 FR 54202, October 6, 1999), applicable to certain McDonnell 
Douglas Model DC-10-10, -15, -30, and -30F (KC-10A military) series 
airplanes, and Model MD-10-10F and -30F series airplanes, to require 
inspections to determine the condition of the lockwires on the forward 
engine mount bolts and correction of any discrepancies found. That AD 
also provides for optional terminating actions for the repetitive 
inspections. That action was prompted by reports of stretched or broken 
lockwires on the forward engine mount bolts. The requirements of that 
AD are intended to prevent broken lockwires, which could result in 
loosening of the engine mount bolts, and consequent separation of the 
engine from the airplane.

Actions Since Issuance of Previous Rule

    Since the issuance of that AD, the FAA has received a report of 
discrepant forward engine mount bolts at the number 3 engine on a 
McDonnell Douglas Model DC-10-30F (KC-10A military) series airplane. 
Both forward engine mount bolts had broken safety wires and had backed 
out approximately \1/4\ inch. This airplane had been only inspected per 
AD 95-04-07 R2.
    The FAA has determined that repetitive inspections to determine the 
condition of the lockwires on the forward engine mount bolts, as 
required by AD 95-04-07 R2, do not adequately preclude broken 
lockwires, which could result in loosening of the engine mount bolts, 
and consequent separation of the engine from the airplane. However, we 
find that the optional terminating actions (i.e., installation of 
retainers on the engine mount bolts of engines 1, 2, or 3, or 
modification of the forward engine mount bolts for engine 1, 2, or 3; 
as applicable) specified in that AD do adequately address the 
identified unsafe condition.

Explanation of Relevant Service Information

    The FAA has reviewed and approved McDonnell Douglas Service 
Bulletins DC10-71-159 [for Model DC-10-10, -15, -30, and -30F (KC-10A 
military) series airplanes, and Model MD-10-10F and -30F series 
airplanes], dated September 6, 1995, and Revision 01, dated July 28, 
1997. This service bulletin describes procedures for modification of 
the forward engine mount bolts of engines 1, 2, and 3, which would 
eliminate the need for the repetitive inspections. This involves 
removal of the existing lockwires from the forward engine mount bolts, 
modification and reidentification of the anti-ice duct, and 
installation of retainers on the forward engine mount bolts.
    The FAA also has reviewed and approved McDonnell Douglas DC-10 
Service Bulletin 71-133, Revision 6, dated June 30, 1992 [for Model DC-
10-30 and -30F (KC-10A military) series airplanes, and Model MD-10-30F 
series airplanes]. This service bulletin describes procedures for 
installation of retainers on the engine mount bolts of engines 1, 2, or 
3, which would eliminate the need for the repetitive inspections.
    Accomplishment of the actions specified in the applicable 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, the 
proposed AD would supersede AD 95-04-07 R2 to continue to require 
repetitive visual inspections to determine the condition of the 
lockwires on the forward engine mount bolts and correction of any 
discrepancies found. The proposed AD also would require accomplishment 
of the action specified in the applicable service bulletin described 
previously, which would constitute terminating action for the 
repetitive inspection requirements.

Explanation of Change to the Applicability of the Existing AD

    On May 9, 2000 (i.e., after issuance of AD 95-04-07 R2), the FAA 
issued a Type Certificate (TC) for McDonnell Douglas Model MD-10-10F 
and MD-10-30F series airplanes. Model MD-10 series airplanes are Model 
DC-10 series airplanes that have been modified with an Advanced 
cockpit. The lockwires on the forward engine mount bolts installed on 
Model MD-10-10F and MD-10-30F series airplanes (before or after the 
modifications necessary to meet the type design of a Model MD-10 series 
airplane) are identical to those on the affected Model DC-10-10, -15, -
30, and -30F (KC-10 military) series airplanes. Therefore, all of these 
airplanes may be subject to the same unsafe condition. In addition, the 
manufacturer's fuselage number and factory serial number are not 
changed during the conversion from a Model DC-10 to Model MD-10. 
Although Model DC-10-10F and MD-10-30F series airplanes were not 
specifically identified by model in the applicability of AD 95-04-07 
R2, they were affected by that AD. Therefore, the applicability of the 
proposed AD also includes Model MD-10-10F and MD-10-30F series 
airplanes.

Cost Impact

    There are approximately 389 Model DC-10-10, -15, -30, and -30F (KC-
10A military) series airplanes, and Model MD-10-10F and -30F series 
airplanes of the affected design in the worldwide fleet. The FAA 
estimates that 229 airplanes of U.S. registry would be affected by this 
proposed AD.
    The actions that are currently required by AD 95-04-07 R2, and

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retained in this proposed AD, take approximately 2 work hours per 
airplane to accomplish, at an average labor rate of $60 per work hour. 
Based on these figures, the cost impact of the currently required 
actions on U.S. operators is estimated to be $27,480, or $120 per 
airplane, per inspection cycle
    Should an operator be required to accomplish the proposed 
terminating installation specified in McDonnell Douglas DC-10 Service 
Bulletin 71-133, it would take approximately 4 work hours per airplane 
to accomplish, at an average labor rate of $60 per hour. Required parts 
would cost between $2,744 and $2,822 per airplane. Based on these 
figures, the cost impact of the terminating installation proposed by 
this on U.S. operators is estimated to be between $2,984 and $3,062 per 
airplane.
    Should an operator be required to accomplish the terminating 
modification specified in McDonnell Douglas Service Bulletin DC10-71-
159, it would take approximately 16 work hours per airplane to 
accomplish this required action, at an average labor rate of $60 per 
work hour. Required parts would cost between $2,744 and $2,822 per 
airplane. Based on these figures, the cost impact of the terminating 
modification proposed by this AD on U.S. operators is estimated to be 
between $3,704 and $3,782 per airplane.
    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.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-11354 (64 FR 
54202, October 6, 1999), and by adding a new airworthiness directive 
(AD), to read as follows:

McDonnell Douglas: Docket 2000-NM-410-AD. Supersedes AD 95-04-07 R2, 
Amendment 39-11354.

    Applicability: The following airplanes, certificated in any 
category:

 
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                 Model                         Excluding airplanes
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1. DC-10-30 and -30F (KC-10A military)   On which bolt retainers have
 series airplanes, and MD-10-30F series   been installed on the engine
 airplanes.                               mount per McDonnell Douglas DC-
                                          10 Service Bulletin 71-133,
                                          Revision 6, dated June 30,
                                          1992.
2. DC-10-10, 10-15, -10-30 and -10-30F   On which the modification
 (KC-10A military) series airplanes,      specified in McDonnell Douglas
 and Model MD-10-10F and -30F series      Service Bulletin DC10-71-159,
 airplanes.                               dated September 6, 1995, or
                                          Revision 01, dated July 28,
                                          1997, has been done.
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    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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 (d)(1) 
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 broken lockwires, which could result in loosening of 
the engine mount bolts, and consequent separation of the engine from 
the airplane, accomplish the following:

Restatement of Requirements of AD 95-04-07 R2, Amendment 39-11354

    (a) Within 120 days after March 17, 1995 (the effective date of 
AD 95-04-07 R1, amendment 39-9317), unless accomplished previously 
within the last 750 flight hours prior to March 17, 1995, perform a 
visual inspection to detect broken lockwires on the forward engine 
mount bolts on engines 1, 2, and 3, in accordance with McDonnell 
Douglas Alert Service Bulletin DC10-71A159, Revision 1, dated 
January 31, 1995.
    (1) If no lockwire is found broken, repeat the inspection 
thereafter at intervals not to exceed 750 flight hours.
    (2) If any lockwire is found broken, prior to further flight: 
Check the torque of the bolt, install a new lockwire, and install a 
torque stripe on the bolt, in accordance with the alert service 
bulletin. Thereafter at intervals not to exceed 750 flight hours, 
perform a visual inspection to detect misalignment of the torque 
stripes, and repeat the inspection to detect broken lockwires, in 
accordance with the alert service bulletin.

Terminating Actions

    (b) For Model DC-10-30 and -30F (KC-10A military) series 
airplanes, and Model MD-10-30F series airplanes: Within 18 months 
after the effective date of this AD, install retainers on the engine 
mount bolts of engines 1, 2, or 3 per the procedures depicted in 
Figure 6 of Revision 6 of McDonnell Douglas DC-10 Service Bulletin 
71-133, dated June 30, 1992. Accomplishment of the

[[Page 15820]]

installation constitutes terminating action for the requirements of 
this AD for that engine.
    (c) For Model DC-10-10, -15, -30, and -30F (KC-10A military) 
series airplanes, and Model MD-10-10F and -30F series airplanes: 
Within 18 months after the effective date of this AD, modify the 
forward engine mount bolts for engine 1, 2, or 3, per McDonnell 
Douglas Service Bulletin DC10-71-159, dated September 6, 1995, or 
Revision 01, dated July 28, 1997. Accomplishment of the modification 
constitutes terminating action for the requirements of this AD for 
that engine.

Alternative Methods of Compliance

    (d)(1) 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. 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 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles ACO.

    (2) Alternative methods of compliance, approved previously in 
accordance with AD 95-04-07 R2, amendment 39-11354, are approved as 
alternative methods of compliance with this AD.

Special Flight Permits

    (e) 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 March 14, 2001.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-6941 Filed 3-20-01; 8:45 am]
BILLING CODE 4910-13-P