[Federal Register Volume 65, Number 91 (Wednesday, May 10, 2000)]
[Proposed Rules]
[Pages 30021-30023]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-11724]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-50-AD]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model DC-10-10, -15, 
-30, -30F (KC-10A Military), and -40 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 
DC-10-10, -15, -30, -30F (KC-10A military), and -40 series airplanes. 
This proposal would require performing repetitive ultrasonic 
inspections of the attaching bolts on the inboard and outboard support 
on the inboard and outboard flap assembly to detect failed bolts, or 
verifying the torque of the attaching bolts on the inboard support on 
the outboard flap; and follow-on actions. This proposal also would 
require replacing all bolts with bolts made from Inconel, which would 
constitute terminating action for the repetitive inspection 
requirements. This proposal is prompted by a report of an in-flight 
loss of the inboard flap assembly on an airplane during approach for 
landing. The actions specified by the proposed AD are intended to 
prevent in-flight loss of inboard and outboard flap assemblies due to 
failure of H-11 attaching bolts, which could result in reduced 
controllability of the airplane.

DATES: Comments must be received by June 26, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-50-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.
    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: Ron Atmur, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Transport Airplane Directorate, 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 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 2000-NM-50-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-50-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received a report of an in-flight loss of the left 
inboard flap assembly on a McDonnell Douglas Model DC-10 series 
airplane during approach for landing. Investigation revealed that bolts 
made from H-11 steel, which attach the outboard hinge to the lower 
surface of the flap, had failed. Analysis of the bolts determined the 
cause of failure to be stress corrosion. The FAA has received no damage 
or failure reports about the outboard flaps. However, the inboard and 
outboard hinges are attached to the lower surface of the flap using 
similar type design and the same material as the installation of the 
inboard flap outboard hinge. Failure of H-11 attaching bolts could 
result in an in-flight loss of inboard and outboard flap assemblies, 
and consequent reduced controllability of the airplane.

Explanation of Relevant Service Information

    The FAA has reviewed and approved McDonnell Douglas Alert Service 
Bulletin DC10-57A143, dated December

[[Page 30022]]

20, 1999. The service bulletin describes procedures for performing an 
ultrasonic inspection of the attaching bolts on the inboard and 
outboard support on the inboard and outboard flap assembly to detect 
failed bolts, or verifying the torque of the attaching bolts on the 
inboard support on the outboard flap, and follow-on actions. The 
follow-on actions include replacing any failed bolt and associated 
parts, if necessary; performing repetitive ultrasonic inspection of the 
subject area, if necessary; temporarily installing a new Inconel bolt 
without a new PLI washer; and replacing the PLI washer with a new 
washer; if necessary. The service bulletin also describes procedures 
for replacing all bolts with bolts made from Inconel, which would 
eliminate the need for the repetitive inspections.
    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, the 
proposed AD would require accomplishment of the actions specified in 
the service bulletin described previously.

Cost Impact

    There are approximately 412 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 244 airplanes of U.S. registry 
would be affected by this proposed AD.
    It would take between 2 and 8 work hours per airplane to accomplish 
the proposed inspection/torque verification, at an average labor rate 
of $60 per work hour. Based on these figures, the cost impact of the 
inspection/torque verification proposed by this AD on U.S. operators is 
estimated to be between $29,280 and $117,120, or between $120 and $480 
per airplane, per inspection cycle.
    It would take approximately 288 work hours per airplane to 
accomplish the proposed bolt replacement, at an average labor rate of 
$60 per work hour. Required parts would cost approximately $2,987 per 
airplane. Based on these figures, the cost impact of the replacement 
proposed by this AD on U.S. operators is estimated to be $4,945,148, or 
$20,267 per airplane.
    The cost impact figures discussed above are 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 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 2000-NM-50-AD.

    Applicability: Model DC-10-10, -15, -30, -30F (KC-10A military), 
and -40 series airplanes, as listed in McDonnell Douglas Alert 
Service Bulletin DC10-57A143, dated December 20, 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 (d) 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 in-flight loss of inboard and outboard flap 
assemblies due to failure of H-11 attaching bolts, which could 
result in reduced controllability of the airplane, accomplish the 
following:

Inspection and Corrective Actions

    (a) Within 2 months after the effective date of this AD, perform 
an ultrasonic inspection of the attaching bolts on the inboard and 
outboard support on the inboard and outboard flap assembly to detect 
failed bolts, or verify the torque of the attaching bolts on the 
inboard support on the outboard flap, in accordance with McDonnell 
Douglas Alert Service Bulletin DC10-57A143, dated December 20, 1999.
    (1) If no failed bolt is found, repeat the ultrasonic inspection 
thereafter at intervals not to exceed 6 months.
    (2) If any failed bolt is found, prior to further flight, 
replace the bolt and associated parts with a new Inconel bolt and 
new associated parts in accordance with the service bulletin, except 
as provided by paragraphs (a)(2)(i) and (a)(2)(ii) of this AD. 
Accomplishment of the replacement constitutes terminating action for 
the repetitive inspection requirements of paragraph (a)(1) of this 
AD for that bolt.
    (i) If an Inconel bolt is not available for accomplishment of 
the replacement, replacement with a new H-11 steel bolt is 
acceptable provided that operators repeat the ultrasonic inspection 
thereafter at intervals not to exceed 6 months until the 
requirements of paragraph (b) of this AD are accomplished.
    (ii) If a PLI washer is not available for accomplishment of the 
Inconel replacement, a new Inconel bolt can be temporarily installed 
without a new PLI washer provided that the bolt is torqued to the 
applicable value specified in the service bulletin. Within 6,000 
flight hours after an Inconel bolt is torqued, replace the PLI 
washer with a new washer in accordance with the service bulletin.

Bolt Replacement

    (b) Within 2 years after accomplishing the initial inspection 
required by paragraph (a) of this AD, accomplish the action 
specified in paragraph (a)(2) of this AD for all H-11 bolts. 
Accomplishment of the replacement of all H-11 bolts with Inconcel 
bolts constitutes terminating action for the requirements of this 
AD.

Spares

    (c) As of 2 years after the effective date of this AD, no person 
shall install, on any

[[Page 30023]]

airplane, an H-11 steel bolt, part number 71658-8-44, 71658-7-44, 
71658-7-54, 71658-7-56, 71658-7-29, 71658-9-31, 71658-9-34, 71658-9-
38, 71658-9-41, 71658-10-41, 71658-7-26, 71658-7-27, or 71658-8-29, 
on the inboard or outboard flap assembly.

Alternative Methods of Compliance

    (d) 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 2: 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

    (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 May 4, 2000.
Vi L. Lipski,
 Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-11724 Filed 5-9-00; 8:45 am]
BILLING CODE 4910-13-U