[Federal Register Volume 59, Number 86 (Thursday, May 5, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-10506]


[[Page Unknown]]

[Federal Register: May 5, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-NM-53-AD; Amendment 39-8906; AD 94-09-17]

 

Airworthiness Directives; McDonnell Douglas Model DC-10 Series 
Airplanes and KC-10A (Military) Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to all McDonnell Douglas Model DC-10 series airplanes and 
KC-10A (military) airplanes. This action requires inspections to 
determine the serial numbers and to detect defects in the upper and 
lower lock links on the nose landing gear (NLG), and rework or 
replacement of any defective link found. This amendment is prompted by 
reports of cracking and subsequent failure of certain lock links on 
these airplanes, which have been attributed to forging defects in the 
lock links. The actions specified in this AD are intended to prevent 
collapse of the NLG.

DATES: Effective May 20, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 20, 1994.
    Comments for inclusion in the Rules Docket must be received on or 
before July 5, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-53-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056.
    The service information referenced in this AD may be obtained from 
McDonnell Douglas Corporation, P.O. Box 1771, Long Beach, California 
90801-1771, Attention: Business Unit Manager, Technical Administrative 
Support, Dept. L51, M.C. 2-98. 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, 3229 East Spring Street, Long Beach, 
California; or at the Office of the Federal Register, 800 North Capitol 
Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Maureen Moreland, Aerospace Engineer, 
Airframe Branch, ANM-121L, FAA, Transport Airplane Directorate, Los 
Angeles Aircraft Certification Office, 3229 East Spring Street, Long 
Beach, California 90806-2425; telephone (310) 988-5238; fax (310) 988-
5210.

SUPPLEMENTARY INFORMATION: The FAA has received a report of cracking 
and subsequent failure of an upper lock link on the center landing gear 
(CLG) of a McDonnell Douglas Model MD-11 series airplane. Results of a 
subsequent analysis attributed the failure to forging defects in the 
lock link. An investigation conducted by the manufacturer revealed two 
additional upper links on the CLG with similar forging defects. The 
lower lock link on the CLG and the upper and lower lock links on the 
nose landing gear (NLG) are similar in design and are manufactured by 
the same supplier as the upper lock link on the CLG; therefore, 
defective lock links could be installed at any of these locations. 
Failure of the lock links on the CLG would result in collapse of the 
CLG; collapse of the CLG would not present an unsafe condition. 
However, cracking and subsequent failure of the lock links on the NLG, 
if not corrected, could result in collapse of the NLG. This situation 
could result in reduced controllability of the airplane during takeoff 
or landing.
    The FAA has issued a separate AD to address this unsafe condition 
on Model MD-11 series airplanes [reference AD 94-09-01, amendment 39-
8889 (59 FR 18722, April 20, 1994)]. However, since the NLG lock links 
used on Model MD-11 series airplanes can also be used on Model DC-10 
series airplanes and KC-10A (military) airplanes, the FAA finds that 
the latter airplane models also are subject to the identified unsafe 
condition.
    The FAA has reviewed and approved McDonnell Douglas DC-10 Alert 
Service Bulletin A32-237, dated April 11, 1994, that describes 
procedures for a visual inspection to determine the serial numbers of 
the upper and lower NLG lock links; an eddy current inspection to 
detect defects in suspect lock links; and rework of any defective lock 
link found, or replacement of any defective lock link with a servicable 
link. Reworking or replacing the lock links will minimize the 
possibility of failure of the lock links on NLG and subsequent collapse 
of a landing gear.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other Model DC-10 series airplanes and KC-10A 
(military) airplanes of the same type design, this AD is being issued 
to prevent collapse of the NLG. This AD requires inspections to 
determine the serial numbers and to detect defects in the upper and 
lower lock links on the NLG, and rework or replacement of any defective 
link found. The actions are required to be accomplished in accordance 
with the service bulletin described previously. This AD also requires 
that operators submit a report of inspection findings to the FAA.
    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.
    The required compliance time of 120 days is usually sufficient to 
allow for a brief comment period before adoption of a final rule. In 
this AD, however, that compliance time was selected because of a short-
term problem with availability of sufficient replacement parts if 
defects are found; a shorter compliance time might have resulted in the 
unnecessary removal of airplanes from service pending delivery of 
replacement parts. Nevertheless, the FAA has determined that immediate 
adoption is necessary in this case because of the importance of 
initiating the required inspections as soon as possible.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD 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 94-NM-53-AD.'' The postcard will be date stamped and 
returned to the commenter.
    The regulations adopted herein will 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 final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and is not a ``significant regulatory action'' 
under Executive Order 12866. It has been determined further that this 
action involves an emergency regulation under DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979). If it is determined 
that this emergency regulation otherwise would be significant under DOT 
Regulatory Policies and Procedures, a final regulatory evaluation will 
be prepared and placed in the Rules Docket. A copy of it, if filed, may 
be obtained from the Rules Docket at the location provided under the 
caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 14 CFR part 
39 of the Federal Aviation Regulations as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

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

94-09-17 McDonnell Douglas: Amendment 39-8906. Docket 94-NM-53-AD.

    Applicability: All Model DC-10 series airplanes and KC-10A 
(military) airplanes, certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent collapse of the nose landing gear (NLG), accomplish 
the following:
    (a) Within 120 days after the effective date of this AD, perform 
a visual inspection to determine the serial number of the upper lock 
links, part number ACG7396-1, and lower lock links, part number 
ACG7237-1, on the NLG; in accordance with McDonnell Douglas DC-10 
Alert Service Bulletin A32-237, dated April 11, 1994.
    (b) If the serial number of the lock link coincides with any of 
the suspect serial numbers listed in McDonnell Douglas DC-10 Alert 
Service Bulletin A32-237, dated April 11, 1994, perform an eddy 
current inspection to detect defects in the suspect lock link, in 
accordance with the alert service bulletin.
    (c) If any defect is found, prior to further flight, accomplish 
either paragraph (c)(1) or (c)(2) of this AD in accordance with 
McDonnell Douglas DC-10 Alert Service Bulletin A32-237, dated April 
11, 1994.
    (1) Rework the lock link. Or
    (2) Replace the defective lock link with a serviceable lock link 
that has been inspected in accordance with paragraphs (a) and (b) of 
this AD, or that has been reworked in accordance with paragraph 
(c)(1) of this AD.
    (d) Within 10 days after accomplishing the inspection required 
by paragraph (b) of this AD, submit a report of inspection findings 
to the Manager, Los Angeles Aircraft Certification Office (ACO), 
3229 East Spring Street, Long Beach, California 90806-2425; fax 
(310) 988-5210. The report must include the inspection results, a 
description of any discrepancy found, the part numbers of all links 
inspected, the airplane serial number, and the number of landings 
and flight hours on the airplane. Information collection 
requirements contained in this regulation have been approved by the 
Office of Management and Budget (OMB) under the provisions of the 
Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have 
been assigned OMB Control Number 2120-0056.
    (e) As of the effective date of this AD, no person shall install 
an upper lock link, part number ACG7396-1, or a lower lock link, 
part number ACG7237-1, on the NLG of any airplane unless that lock 
link has been inspected in accordance with McDonnell Douglas DC-10 
Alert Service Bulletin A32-237, dated April 11, 1994.
    (f) 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: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles ACO.

    (g) Special flight permits may be issued in accordance with 
Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the 
airplane to a location where the requirements of this AD can be 
accomplished.
    (h) The actions shall be done in accordance with McDonnell 
Douglas DC-10 Alert Service Bulletin A32-237, dated April 11, 1994. 
This incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from McDonnell Douglas Corporation, P.O. 
Box 1771, Long Beach, California 90801-1771, Attention: Business 
Unit Manager, Technical Administrative Support, Dept. L51, M.C. 2-
98. Copies may be inspected at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the 
FAA, Transport Airplane Directorate, Los Angeles Aircraft 
Certification Office, 3229 East Spring Street, Long Beach, 
California; or at the Office of the Federal Register, 800 North 
Capitol Street, NW., suite 700, Washington, DC.
    (i) This amendment becomes effective on May 20, 1994.

    Issued in Renton, Washington, on April 26, 1994.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-10506 Filed 5-4-94; 8:45 am]
BILLING CODE 4910-13-U