[Federal Register Volume 68, Number 8 (Monday, January 13, 2003)]
[Rules and Regulations]
[Pages 1519-1521]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-331]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NE-44-AD; Amendment 39-13016; AD 2003-01-05]
RIN 2120-AA64


Airworthiness Directives; General Electric Co. CF6-80A 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 applicable to General Electric Co. (GE) CF6-80A series turbofan 
engines. This action requires the following initial and repetitive 
inspections of certain part number (P/N) stage 1 high pressure turbine 
(HPT) rotor disks for cracks:
    [sbull] Etch preparations and fluorescent penetrant inspections.
    [sbull] Visual inspections.
    [sbull] Eddy current inspections.

This amendment is prompted by a Boeing 767 airplane recently 
experiencing a stage 1 HPT rotor disk separation resulting in 
uncontained engine failure. The actions specified in this AD are 
intended to detect cracks in the bottoms of the dovetail slots that 
could propagate to failure of the disk and cause an uncontained engine 
failure.

DATES: Effective January 28, 2003. The incorporation by reference of 
certain publications listed in the rule is approved by the Director of 
the Federal Register as of January 28, 2003.
    Comments for inclusion in the Rules Docket must be received on or 
before March 14, 2003.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 2002-NE-44-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may be inspected at 
this location, by appointment, between 8 a.m. and 4:30 p.m., Monday 
through Friday, except Federal holidays. Comments may also be sent via 
the Internet using the following address: ``[email protected]''. 
Comments sent via the Internet must contain the docket number in the 
subject line.
    The service information referenced in this AD may be obtained from 
General Electric Company via Lockheed Martin Technology Services, 10525 
Chester Road, Suite C, Cincinnati, Ohio 45215, telephone (513) 672-
8400, fax (513) 672-8422. This information may be examined, by 
appointment, at the FAA, New England Region, Office of the Regional 
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: Anthony W. Cerra Jr., Aerospace 
Engineer, Engine Certification Office, FAA, Engine and Propeller 
Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; 
telephone: (781) 238-7128, fax: (781) 238-7199.

SUPPLEMENTARY INFORMATION: On December 8, 2002, a Boeing 767-200 
equipped with GE CF6-80A series engines experienced an uncontained 
failure of a stage 1 HPT rotor disk during climb. The results of the 
investigation indicate that the stage 1 HPT rotor disk failure was the 
result of a crack that initiated in an aft corner edge of the bottom of 
a dovetail slot. The crack propagated in fatigue to critical crack 
size, and subsequently resulted in disk rupture and separation.
    In September 2000, a U.S. operator experienced a similar 
uncontained failure of the stage 1 HPT rotor disk during a ground 
maintenance run of a CF6-80C2 engine. The investigation of that failure 
had indicated that a crack initiated in the dovetail slot bottom aft 
edge. The root cause of the crack initiation remains unknown. However, 
cracks, burrs, or damage sustained in the dovetail slot bottom corner 
radii from improper handling and processing during new part manufacture 
and/or during maintenance were suspect for the September 2000 event. AD 
2001-10-07, which became effective on June 28, 2001, was issued to 
mandate inspections of the CF6-80C2 stage 1 HPT rotor disk dovetail 
slot bottoms.
    Since 1995, shop level inspections have found eleven stage 1 HPT 
rotor disks from CF6-80A series engines and CF6-80C2 series engines 
with crack-like indications in the dovetail slot bottoms. These 
indications resulted from material inclusions, toolmarks, broach burrs, 
and unknown causes. Of these eleven disks, three have been CF6-80A 
series engine stage 1 HPT rotor disks, with cracks in the dovetail slot 
bottom aft corner radius. Of the three that have been -80A series 
engine disks, two indications were associated with non-propagating 
broaching burrs occurring during manufacture, while no root cause was 
identified for the third. Only the third disk had crack propagation.
    The failure of the disk involved in the recent CF6-80A series 
engine event was also caused by a crack that initiated in the dovetail 
slot bottom aft edge. This event is still under investigation. 
Therefore, this final rule; request for comments is an interim action 
until a root cause is established for the crack initiation and/or 
additional corrective actions are identified. The actions specified by 
this AD are intended to detect cracks in the bottoms of the dovetail 
slots that could propagate to failure of the disk and cause an 
uncontained engine failure. This condition, if not corrected, could 
result in stage 1 HPT rotor disk separation resulting in uncontained 
engine failure.

Manufacturer's Service Information

    The FAA has reviewed and approved the technical contents of GE 
Service Bulletin (SB) CF6-80A S/B 72-0779, dated March 20, 2002 that 
describes procedures for etch preparation, fluorescent penetrant, 
visual, and eddy current inspections of the following stage 1 HPT rotor 
disks P/N's used on CF6-80A, -80A1, -80A2, and -80A3 series turbofan 
engines:

[[Page 1520]]



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            9234M67G22                   9234M67G24                  9234M67G25                  9234M67G26
            9362M58G02                   9362M58G06                  9362M58G07                  9362M58G09
            9367M45G02                   9367M45G04                  9367M45G09                         N/A
----------------------------------------------------------------------------------------------------------------

Differences Between This AD and the Manufacturer's Service Information

    SB CF6-80A S/B 72-0779, dated March 20, 2002, only requires a one-
time inspection at the next exposure of disks that have accumulated 
operating cycles, and requires no inspection of new disks that have not 
yet accumulated operating cycles. This AD requires initial and 
repetitive inspections of the affected P/N's of stage 1 HPT rotor 
disks, as specified in the following paragraph.

FAA's Determination of an Unsafe Condition and Required Actions

    Since an unsafe condition has been identified that is likely to 
exist or develop on other GE CF6-80A, -80A1, -80A2, and -80A3 series 
turbofan engines of the same type design, this AD is being issued to 
detect cracks in the bottoms of the dovetail slots that could propagate 
to failure of the disk and cause an uncontained engine failure. This AD 
requires:
    [sbull] For stage 1 HPT rotor disks not currently installed in 
engines, before further flight, inspection of disk dovetail slot 
bottoms. Any disk that meets or exceeds the reject criteria of SB CF6-
80A S/B 72-0779, dated March 20, 2002, is not to be installed into any 
engine.
    [sbull] For stage 1 HPT rotor disks that have been inspected in 
accordance with SB CF6-80A S/B 72-0779, dated March 20, 2002, before 
the effective date of this AD, inspection of the disk dovetail slot 
bottoms at each piece-part exposure of the disk, and replacement of 
disks as necessary.
    [sbull] For stage 1 HPT rotor disks that have not been inspected in 
accordance with SB CF6-80A S/B 72-0779, dated March 20, 2002, before 
the effective date of this AD, inspection of the disk dovetail slot 
bottoms at next engine shop visit, and each piece-part exposure of the 
disk, and replacement of disks as necessary.
    [sbull] A mandatory reporting requirement which mandates that 
within 5 calendar days of an inspection, any results that equal or 
exceed the reject criteria be reported to the FAA's Engine and 
Propeller Directorate, Engine Certification Office.
    The actions are required to be done in accordance with the service 
bulletin described previously.

Interim Actions

    The actions specified in the AD are considered interim actions and 
further action is anticipated based on the continuing investigation of 
the stage 1 HPT rotor disk cracking.

Immediate Adoption of This AD

    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 action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2002-NE-44-AD.'' The postcard will be date stamped and 
returned to the commenter.

Regulatory Analysis

    This final rule does not have federalism implications, as defined 
in Executive Order 13132, because it would not have a substantial 
direct effect 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. Accordingly, 
the FAA has not consulted with state authorities prior to publication 
of this final rule.
    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 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:

2003-01-05 General Electric Co.: Amendment 39-13016. Docket No. 
2002-NE-44-AD.

Applicability

    This airworthiness directive (AD) is applicable to General 
Electric Co. (GE) CF6-

[[Page 1521]]

80A, -80A1, -80A2, and -80A3 series turbofan engines with the stage 
1 high pressure turbine (HPT) rotor disks part numbers (P/N's) 
listed in the following Table 1:

                                Table 1.--Stage 1 HPT Rotor Disks P/N's Affected
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            9234M67G22                   9234M67G24                  9234M67G25                  9234M67G26
            9362M58G02                   9362M58G06                  9362M58G07                  9362M58G09
            9367M45G02                   9367M45G04                  9367M45G09                         N/A
----------------------------------------------------------------------------------------------------------------

    These engines are installed on, but not limited to, Airbus 
Industrie A310 and Boeing 767 airplanes.

    Note 1: This 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 request approval for an 
alternative method of compliance in accordance with paragraph (g) 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

    Compliance with this AD is required as indicated, unless already 
done.
    To detect cracks in the bottoms of the dovetail slots that could 
propagate to failure of the disk and cause an uncontained engine 
failure, do the following in accordance with paragraphs 3.A. through 
3.C.(10)(h) of the Accomplishment Instructions of GE Service 
Bulletin (SB) CF6-80A S/B 72-0779, dated March 20, 2002:
    (a) For stage 1 HPT rotor disks not currently installed in 
engines, before further flight, inspect the disk dovetail slot 
bottoms. Do not install any disk that meets or exceeds the reject 
criteria of the above service bulletin, into any engine.
    (b) For stage 1 HPT rotor disks that have been inspected in 
accordance with the above service bulletin before the effective date 
of this AD, inspect the disk dovetail slot bottoms at each piece-
part exposure of the disk, and replace disk as necessary.
    (c) For stage 1 HPT rotor disks that have not been inspected in 
accordance with the above service bulletin before the effective date 
of this AD, inspect the disk dovetail slot bottoms at next engine 
shop visit, and each piece-part exposure of the disk, and replace 
disk as necessary.

Definitions

    (d) An engine shop visit is defined as the induction of an 
engine into a shop, where the separation of a major engine flange 
will occur after the effective date of this AD.
    (e) Piece-part exposure is defined as:
    (1) The part being considered completely disassembled, when done 
in accordance with the disassembly instructions of the 
manufacturer's or other FAA-approved engine manual; AND
    (2) The part has accumulated more than 100 cycles-in-service 
since the last piece-part opportunity inspection, provided that the 
part was not damaged or related to the cause for its removal from 
the engine.

Reporting Requirements

    (f) Report within 5 calendar days of inspection the results of 
inspections that equal or exceed the reject criteria to: Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803-5299; telephone (781) 
238-7128; fax (781) 238-7199. Reporting requirements have been 
approved by the Office of Management and Budget (OMB) control number 
2120-0056. Be sure to include the following information:
    (1) Engine model in which the stage 1 HPT rotor disk was 
installed.
    (2) Disk Part Number.
    (3) Disk Serial Number.
    (4) Disk Cycles-Since-New.
    (5) Disk Cycles-Since-Last Inspection.
    (6) Date and Location of Inspection.

    Note 2: The FAA recommends recording the inspection results on 
GE Form 1653-1, found in GE SB CF6-80A S/B 72-0779, dated March 20, 
2002, and sending the data to GE Airline Support Engineering.

Alternative Methods of Compliance

    (g) 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 (ECO). 
Operators must submit their requests through an appropriate FAA 
Principal Maintenance Inspector, who may add comments and then send 
it to the Manager, ECO.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the ECO.

Special Flight Permits

    (h) Special flight permits may be issued in accordance with 
Sec. Sec.  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 done.

Documents That Have Been Incorporated by Reference

    (i) The inspections must be done in accordance with General 
Electric Co. Service Bulletin CF6-80A S/B 72-0779, dated March 20, 
2002. 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 General Electric Company via 
Lockheed Martin Technology Services, 10525 Chester Road, Suite C, 
Cincinnati, Ohio 45215, telephone (513) 672-8400, fax (513) 672-
8422. Copies may be inspected at the FAA, New England Region, Office 
of the Regional 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.

Effective Date

    (j) This amendment becomes effective on January 28, 2003.

    Issued in Burlington, Massachusetts, on January 2, 2003.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 03-331 Filed 1-10-03; 8:45 am]
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