[Federal Register Volume 59, Number 76 (Wednesday, April 20, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-9471]


[[Page Unknown]]

[Federal Register: April 20, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-NM-45-AD; Amendment 39-8889; AD 94-09-01]

 

Airworthiness Directives; McDonnell Douglas Model MD-11 Series 
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 certain McDonnell Douglas Model MD-11 series 
airplanes. This action requires an eddy current inspection 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 5, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 5, 1994.
    Comments for inclusion in the Rules Docket must be received on or 
before June 20, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-45-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: Wahib Mina, 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) 988-5324; 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 reviewed and approved McDonnell Douglas MD-11 Alert 
Service Bulletin A32-44, dated March 22, 1994, that describes 
procedures for an eddy current inspection to detect defects in the lock 
links of the NLG and CLG on certain airplanes, and rework or 
replacement of any defective lock link found. Reworking or replacing 
the lock links will minimize the possibility of failure of the lock 
links on NLG and CLG and subsequent collapse of a landing gear.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other Model MD-11 series airplanes of the same type 
design, this AD is being issued to prevent collapse of the NLG. This AD 
requires an eddy current inspection 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 alert 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-45-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:

94-09-01  McDonnell Douglas: Amendment 39-8889. Docket 94-NM-45-AD.

    Applicability: Model MD-11 series airplanes; as listed in 
McDonnell Douglas MD-11 Alert Service Bulletin A32-44, dated March 
22, 1994; 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 an eddy current inspection to detect 
defects in the upper lock links, part number ACG7396-1, and lower 
lock links, part number ACG7237-1, on the NLG; in accordance with 
McDonnell Douglas MD-11 Alert Service Bulletin A32-44, dated March 
22, 1994.
    (b) If no defect is found, prior to further flight, identify the 
inspected lock link in accordance with McDonnell Douglas MD-11 Alert 
Service Bulletin A32-44, dated March 22, 1994.
    (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 MD-11 Alert Service Bulletin A32-44, dated March 
22, 1994.
    (1) Rework and identify the lock link. Or
    (2) Replace the defective lock link with a serviceable lock link 
that has been inspected and identified in accordance with paragraphs 
(a) and (b) of this AD.
    (d) Within 10 days after accomplishing the inspection required 
by paragraph (a) 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 and identified in accordance with paragraphs 
(a) and (b) of this AD.
    (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 MD-11 Alert Service Bulletin A32-44, dated March 22, 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 5, 1994.

    Issued in Renton, Washington, on April 14, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-9471 Filed 4-19-94; 8:45 am]
BILLING CODE 4910-13-U