[Federal Register Volume 60, Number 94 (Tuesday, May 16, 1995)]
[Rules and Regulations]
[Pages 25985-25987]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-11904]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-ANE-17; Amendment 39-9228; AD 95-10-11]


Airworthiness Directives; General Electric Company CF6 Series 
Turbofan Engines

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 [[Page 25986]] applicable to General Electric Company (GE) CF6-80C2 
series turbofan engines. This action requires an initial and repetitive 
brake holding torque check of the fan reverser center drive unit (CDU), 
visual inspection of the translating cowl inner bondment seal, and 
functional check of the translating cowl auto re-stow system. This 
action also requires removal and replacement of certain CDU's as a 
terminating action to the repetitive check and inspection program. This 
amendment is prompted by a report of a CDU not able to hold the fan 
reverser translating cowl at the required position when manually driven 
to its stow position during routine maintenance. The actions specified 
in this AD are intended to prevent the loss of the CDU's brake holding 
feature, which could result in possible movement of the fan reverser 
translating cowl towards the deploy position in flight.

DATES: Effective May 31, 1995. -
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 31, 1995.
    Comments for inclusion in the Rules Docket must be received on or 
before July 17, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 95-ANE-17, 12 New England 
Executive Park, Burlington, MA 01803-5299.
    The service information referenced in this AD may be obtained from 
Martin Marietta Services, Inc., Attn: Karen Lyons, 10525 Chester Road, 
Cincinnati, OH 45215. This information may be examined at the FAA, New 
England Region, Office of the Assistant Chief Counsel, 12 New England 
Executive Park, Burlington, MA; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Robert Ganley, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803-5299; telephone (617) 
238-7138; fax (617) 238-7199.

SUPPLEMENTARY INFORMATION: The Federal Aviation Administration (FAA) 
received a report of a center drive unit (CDU) not able to hold the fan 
reverser translating cowl at the required position when manually driven 
to its stow position during routine maintenance. Investigation revealed 
that the CDU brake shaft had worn to the extent that the braking 
feature was inoperative. This feature, in conjunction with two 
additional features (auto re-stow and stow retention), prevents the 
uncommanded movement of the translating cowl towards the deploy 
position. Further investigation revealed that the wear was due to the 
low material hardness of the brake shaft. This low material hardness is 
the result of a heat treat step that was inadvertently omitted from the 
manufacturing cycle of the brake shaft. This condition, if not 
corrected, could result in loss of the CDU's brake holding feature, 
which could result in possible movement of the fan reverser translating 
cowl towards the deploy position in flight.
    The FAA has reviewed and approved the technical contents of Martin 
Marietta CF6-80C2 Service Bulletin (SB) No. 78-1002, Revision 1, dated 
March 23, 1995, that describes procedures for the brake holding torque 
check of the fan reverser CDU, visual inspection of the translating 
cowl inner bondment seal, functional check of the translating cowl auto 
re-stow system, and the removal and replacement of the CDU.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other General Electric Company (GE) CF6-80C2 series 
turbofan engines of the same type design, this AD is being issued to 
prevent the loss of the CDU's brake holding feature, which could result 
in possible movement of the fan reverser translating cowl towards the 
deploy position in flight. This AD requires an initial and repetitive 
brake holding torque check of the fan reverser CDU, visual inspection 
of the translating cowl inner bondment seal, and functional check of 
the translating cowl auto re-stow system. This AD also requires removal 
and replacement of certain CDU's as a terminating action to the 
repetitive check and inspection program. The actions are required to be 
accomplished in accordance with the service bulletin described 
previously.
    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 should 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 95-ANE-17.'' 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.'' [[Page 25987]] 

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:

95-10-11  General Electric Company: Amendment 39-9228. Docket 95-
ANE-17.

    -Applicability: General Electric Company (GE) CF6-80C2 series 
turbofan engines installed on, but not limited to, Airbus A300 and 
A310 series, Boeing 747 and 767 series, and McDonnell Douglas MD-11 
series aircraft.

    Note: This airworthiness directive (AD) applies to each engine 
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 engines that have been 
modified, altered, or repaired so that the performance of the 
requirements of this AD is affected, the owner/operator must use the 
authority provided in paragraph (e) to request approval from the 
Federal Aviation Administration (FAA). This approval may address 
either no action, if the current configuration eliminates the unsafe 
condition, or different actions necessary to address the unsafe 
condition described in this AD. Such a request should include an 
assessment of the effect of the changed configuration on the unsafe 
condition addressed by this AD. In no case does the presence of any 
modification, alteration, or repair remove any engine from the 
applicability of this AD.-

    -Compliance: Required as indicated, unless accomplished 
previously. -
    To prevent a loss of the center drive units (CDU) brake holding 
feature, which could result in possible movement of the fan reverser 
translating cowl towards the deploy position in flight, accomplish 
the following: -
    (a) For fan reversers that have a CDU identified in paragraph 
1.A.(1) of Martin Marietta (MM) CF6-80C2 Service Bulletin (SB) No. 
78-1002, Revision 1, dated March 23, 1995, installed, perform the 
following: -
    (1) If the requirements of MM CF6-80C2 SB No. 78-1002, dated 
February 27, 1995, or MM CF6-80C2 SB No. 78-1002, Revision 1, dated 
March 23, 1995, have not been previously accomplished, perform a 
brake holding torque check of the fan reverser CDU, a visual 
inspection of the translating cowl inner bondment seal, and a 
functional check of the translating cowl auto re-stow system in 
accordance with paragraphs 2.B, 2.C, and 2.D of MM CF6-80C2 SB No. 
78-1002, Revision 1, dated March 23, 1995, prior to accumulating 250 
cycles in service (CIS) or 30 days, after the effective date of this 
AD, whichever occurs earlier.
    (2) If the requirements of MM CF6-80C2 SB No. 78-1002, dated 
February 27, 1995, or MM CF6-80C2 SB No. 78-1002, Revision 1, dated 
March 23, 1995, have been previously accomplished, accomplish the 
following: -
    (i) Perform a brake holding torque check of the fan reverser CDU 
in accordance with paragraph 2.B of MM CF6-80C2 SB No. 78-1002, 
Revision 1, dated March 23, 1995, prior to accumulating 250 CIS 
since the last brake holding torque check. -
    (ii) Perform a visual inspection of the translating cowl inner 
bondment seal, and a functional check of the translating cowl auto 
re-stow system in accordance with paragraphs 2.C and 2.D of MM CF6-
80C2 SB No. 78-1002, Revision 1, dated March 23, 1995, prior to 
accumulating 1,000 hours since the last visual inspection of the 
translating cowl inner bondment seal and functional check of the 
translating cowl auto re-stow system. -
    (b) Thereafter, for fan reversers that have accomplished the 
inspection and check requirements in accordance with paragraph (a) 
of this AD, accomplish the following: -
    (1) Perform a brake holding torque check of the fan reverser CDU 
in accordance with paragraph 2.B of MM CF6-80C2 SB No. 78-1002, 
Revision 1, dated March 23, 1995, prior to accumulating 250 CIS 
since the last brake holding torque check. -
    (2) Perform a visual inspection of the translating cowl inner 
bondment seal, and a functional check of the translating cowl auto 
re-stow system in accordance with paragraphs 2.C and 2.D of MM CF6-
80C2 SB No. 78-1002, Revision 1,dated March 23, 1995, prior to 
accumulating 1,000 hours since the last visual inspection of the 
translating cowl inner bondment seal and functional check of the 
translating cowl auto re-stow system. -
    (c) Remove from service the CDU's identified in paragraph 
1.A.(1) of MM CF6-80C2 SB No. 78-1002, Revision 1, dated March 23, 
1995, in accordance with paragraph 2.F of MM CF6-80C2 SB No. 78-
1002, Revision 1, dated March 23, 1995, prior to December 31, 1995, 
and replace with a serviceable part. Removal and replacement of the 
CDU in accordance with this paragraph constitutes terminating action 
to the initial and repetitive inspection and check requirements of 
paragraph (a) and (b) of this AD. -
    (d) For the purpose of this AD, a serviceable part is defined as 
a CDU that has accomplished any revision level of MM CF6-80C2 SB No. 
78-1014; or a CDU whose shaft has received the hardness inspection 
in accordance with any revision level of GE CF6-80C2 SB No. 78-131, 
and that has not had a brake shaft replacement subsequent to the 
hardness inspection. -
    (e) 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, Engine Certification Office. The 
request should be forwarded through an appropriate FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Engine Certification Office.

    Note: Information concerning the existence of approved alternate 
methods of compliance with this airworthiness directive, if any, may 
be obtained from the Engine Certification Office.

    (f) Special flight permits may be issued in accordance with FAR 
21.197 and 21.199 to operate the aircraft to a location where the 
requirements of this AD can be accomplished.
    (g) The actions required by this AD shall be done in accordance 
with the following service bulletin:

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          Document No.--                        Pages--                     Revision-               Date        
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Martin Marietta CF6-80C2.........  2, 11, 12, 14-18, 20.............  Original............  Feb. 27, 1995.      
SB No. 78-1002-..................  1, 3-10, 13, 19--................  1...................  Mar. 23, 1995.      
    Total pages: 20.                                                                                            
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    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 Martin Marietta Services, Inc., 
Attn: Karen Lyons, 10525 Chester Road, Cincinnati, OH 45215. Copies 
may be inspected at the FAA, New England Region, Office of the 
Assistant Chief Counsel, 12 New England Executive Park, Burlington, 
MA; or at the Office of the Federal Register, 800 North Capitol 
Street, NW., suite 700, Washington, DC. -
    (h) This amendment becomes effective on May 31, 1995.

    Issued in Burlington, Massachusetts, on May 2, 1995.
Mark C. Fulmer,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 95-11904 Filed 5-12-95; 3:16 pm]
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