[Federal Register Volume 59, Number 120 (Thursday, June 23, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 94-15013]


[[Page Unknown]]

[Federal Register: June 23, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 93-NM-168-AD; Amendment 39-8947; AD 94-13-07]

 

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 inspections and replacement or 
reidentification and reinstallation of certain aft engine mount link 
assemblies. This amendment is prompted by reports of cracking in the 
aft engine mount link assemblies of airplanes having link assemblies 
identical to those installed on Model MD-11 series airplanes. The 
actions specified in this AD are intended to prevent loss of the aft 
engine mount capability to support engine loads, and possible 
separation of the engine from the airplane.

DATES: Effective July 8, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of July 8, 1994.
    Comments for inclusion in the Rules Docket must be received on or 
before August 22, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 93-NM-168-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 Publications--
Technical Administrative Support, C1-L5B. This information may be 
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, 
SW., Renton, Washington; or at the FAA, 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 four reports of 
cracking in the aft engine mount link assemblies, part numbers 221-
0262-501 and 221-0262-503, installed on Airbus Industrie Model A310 and 
A300-600 series airplanes. Link assemblies having those part numbers 
are installed in conjunction with Pratt & Whitney (PW) 4000 series 
engines that are installed on those Airbus models, as well as on 
McDonnell Douglas Model MD-11 series airplanes.
    Metallurgical analysis and close examination of the cracked links 
has indicated a similar mode of cracking among the four cracked links 
reported. This cracking is the result of physical defects, which were 
caused during the forging process by one supplier.
    A link assembly is located at all three positions of the aft engine 
mount (left outboard, right outboard, and inboard) installed on Model 
MD-11 series airplanes. Cracks in these aft engine mount link 
assemblies, if not detected and corrected, could result in loss of the 
capability of the aft engine mount to support engine loads, and 
possible separation of the engine from the airplane.
    The FAA has reviewed and approved McDonnell Douglas MD-11 Alert 
Service Bulletin A71-59, dated December 20, 1993, and Revision 1, dated 
January 14, 1994, which contain general information concerning 
procedures to inspect for and replace the suspect engine mount links. 
This service bulletin references Pratt & Whitney Service Bulletin 
APW4MD11 71-86, dated December 20, 1993, for additional service 
information. The Pratt & Whitney service bulletin describes procedures 
for:
    1. A visual inspection of the aft engine mount link assembly, part 
numbers 221-0262-501 and 221-0262-503, at all three link positions 
(left outboard, right outboard, and inboard) to determine the serial 
numbers of the links.
    2. Removal of any suspect link that is found during the visual 
inspection; a fluorescent penetrant inspection and an eddy current 
inspection to detect cracks or other defects in the suspect link; and 
replacement of any cracked or defective suspect link with a link having 
a serial number that is not within the suspect serial number groups.
    3. Replacement of any suspect link that is not cracked or defective 
with a link having a serial number that is not within the suspect 
serial number groups, or reidentification and reinstallation of the 
uncracked suspect link.
    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 loss of the capability of 
the aft engine mount to support engine loads, and possible separation 
of the engine from the airplane.
    This AD requires a visual inspection of the aft engine mount link 
assembly, part numbers 221-0262-501 and 221-0262-503, at all three link 
positions (left outboard, right outboard, and inboard) to determine the 
serial numbers of the links. If any suspect link is found, operators 
are required to remove the link and perform both a fluorescent 
penetrant inspection and an eddy current inspection of it to detect 
cracks and other defects, and to replace any cracked or defective 
suspect link with a link having a serial number that is not within the 
suspect serial number groups. If no crack or defect is found in the 
link, it may either be replaced with a non-suspect link, or 
reidentified and reinstalled. The actions are required to be 
accomplished in accordance with the McDonnell Douglas alert service 
bulletin described previously.
    This AD also requires that operators report certain inspection 
findings to the FAA.
    The FAA has initiated a similar rulemaking action that is 
applicable to Airbus series airplanes on which the suspect links may 
also be installed.
    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.

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 93-NM-168-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 and that it 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 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. 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:

94-13-07 McDonnell Douglas: Amendment 39-8947. Docket 93-NM-168-AD.

    Applicability: Model MD-11 series airplanes; manufacturer's 
fuselage numbers 449, 456 through 461 inclusive, 463 through 465 
inclusive, 472, 473, 475, 477, 480, 481, 484, 485, 487, 489, 490, 
494 through 496 inclusive, 498, 502, 506, 509 through 512 inclusive, 
514, 516, 518, 519, 522, 525, 532, 533, 536, 538, 539, 541 through 
544 inclusive, and 546; certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent the loss of the aft engine mount capability to 
support engine loads and possible separation of the engine from the 
airplane, accomplish the following:
    (a) Perform a visual inspection of the aft engine mount link 
assembly, part numbers 221-0262-501 and 221-0262-503, at all three 
link positions (left outboard, right outboard, and inboard) to 
determine the serial numbers of the links and to identify any 
suspect link that is installed, in accordance with McDonnell Douglas 
MD-11 Alert Service Bulletin A71-59, dated December 20, 1993, or 
Revision 1, dated January 14, 1994, at the time specified in 
paragraph (a)(1) or (a)(2) of this AD, as applicable. Suspect links 
are those links having serial numbers WPC0001 through WPC1063 
inclusive, or M1064 through M1255 inclusive. If no suspect link is 
installed, no further action is required by this AD.

    Note 1: Links having serial numbers M1255 and below with the 
``M'' prefix are from the same forging supplier as links having the 
``WPC'' prefix.

    (1) For airplanes equipped with engines that have experienced a 
high power surge within the last 12 months prior to the effective 
date of this AD: Perform the inspection within 60 days after the 
effective date of this AD.
    (2) For airplanes equipped with engines that have not 
experienced a high power surge within the last 12 months prior to 
the effective date of this AD: Perform the inspection within 120 
days after the effective date of this AD.
    (b) If any suspect link is found during the inspection required 
by paragraph (a) of this AD, prior to further flight, remove the 
suspect link, and perform a fluorescent penetrant inspection and an 
eddy current inspection to detect cracks or other defects in the 
suspect link, in accordance with McDonnell Douglas MD-11 Alert 
Service Bulletin A71-59, dated December 20, 1993, or Revision 1, 
dated January 14, 1994.
    (1) If any crack or defect is found in the link, prior to 
further flight, replace it with a link having a serial number that 
is not within the suspect serial number groups, in accordance with 
the service bulletin.
    (2) If no crack or defect is found in the link, prior to further 
flight, replace it with a link having a serial number that is not 
within the suspect serial number groups, or reidentify and reinstall 
the uncracked suspect link in accordance with the service bulletin. 
No further action is required by this AD for that link.
    (c) Within 10 days after accomplishing the inspection required 
by paragraph (b) of this AD, submit a report of inspection findings, 
including the information specified in paragraphs (c)(1), (c)(2), 
and (c)(3) of this AD, to the Manager, Los Angeles Aircraft 
Certification Office (ACO), FAA, Transport Airplane Directorate, 
3229 East Spring Street, Long Beach, California 90806-2425; fax 
(310) 988-5210. 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.
    (1) The serial number of any suspect link found.
    (2) The manufacturer's fuselage number on which the suspect link 
was found.
    (3) The results of inspections required by paragraph (b) of this 
AD .
    (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.

    (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.
    (f) The actions shall be done in accordance with McDonnell 
Douglas MD-11 Alert Service Bulletin A71-59, dated December 20, 
1993, or McDonnell Douglas MD-11 Alert Service Bulletin A71-59, 
Revision 1, dated January 14, 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 
Publications--Technical Administrative Support, C1-L5B. 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.
    (g) This amendment becomes effective on July 8, 1993.

    Issued in Renton, Washington, on June 15, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-15013 Filed 6-22-94; 8:45 am]
BILLING CODE 4910-13-U