Document ID: FAA-2008-1206-0001
Agency: faa
Document Type: Rule
Title: Airworthiness Directives; General Electric Co. (GE) CF6-80A Series Turbofan Engines
Posted Date: 2008-11-14T05:00Z

[Federal Register: November 14, 2008 (Volume 73, Number 221)]
[Proposed Rules]               
[Page 67433-67435]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr14no08-38]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-1206; Directorate Identifier 2008-NE-19-AD]
RIN 2120-AA64

 
Airworthiness Directives; General Electric Co. (GE) CF6-80A 
Series Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for GE CF6-80A series turbofan engines with a high-pressure turbine 
rotor (HPTR) stage 1 disk, part number (P/N) 9367M45G06, installed. 
This proposed AD would require removing any HPTR stage 1 disk, P/N 
9367M45G06, before exceeding 2,075 cycles-since-new (CSN). This 
proposed AD results from an error by GE that incorrectly cited a cyclic 
life of 12,600 CSN for the HPTR stage 1 disk, P/N 9367M45G06. We are 
proposing this AD to prevent the HPTR stage 1 disk from exceeding its 
part life which could cause fatigue cracks to start and grow. These 
cracks could result in a possible uncontained disk failure and damage 
to the airplane.

DATES: We must receive any comments on this proposed AD by January 13, 
2009.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD.
     Federal eRulemaking Portal: Go to http://
www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 1200 New Jersey Avenue, SE., West Building Ground 
Floor, Room W12-140, Washington, DC 20590-0001.

[[Page 67434]]

     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
     Fax: (202) 493-2251.

FOR FURTHER INFORMATION CONTACT: Robert Green, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; e-mail: 
robert.green@faa.gov; telephone (781) 238-7754; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send us any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2008-1206; Directorate 
Identifier 2008-NE-19-AD'' in the subject line of your comments. We 
specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of the proposed AD. We will consider 
all comments received by the closing date and may amend the proposed AD 
in light of those comments.
    We will post all comments we receive, without change, to http://
www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact 
with FAA personnel concerning this proposed AD. Using the search 
function of the Web site, anyone can find and read the comments in any 
of our dockets, including, if provided, the name of the individual who 
sent the comment (or signed the comment on behalf of an association, 
business, labor union, etc.). You may review the DOT's complete Privacy 
Act Statement in the Federal Register published on April 11, 2000 (65 
FR 19477-78).

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Operations office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Operations office (telephone (800) 647-5527) is 
the same as the Mail address provided in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

Discussion

    During a recent GE internal audit, comparing the life-limited parts 
certification documents to the part life limits specified in the 
Airworthiness Limitations Section of the Instructions for Continuing 
Airworthiness, GE found that the life limits for the CF6-80A series 
engines incorrectly specified a cyclic life of 12,600 CSN for the HPTR 
stage 1 disk, P/N 9367M45G06. GE has determined that the correct life 
limit for the HPTR stage 1 disk, P/N 9367M45G06, is 2,075 CSN. Failure 
to remove these disks from service before exceeding the new, reduced 
life limit of 2,075 CSN could result in fatigue cracks, leading to a 
possible uncontained disk failure and damage to the airplane.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other products 
of this same type design. We are proposing this AD, which would require 
removing from service any HPTR stage 1 disk, P/N 9367M45G06, before it 
exceeds 2,075 CSN.

Costs of Compliance

    We estimate that this proposed AD would affect 10 engines installed 
on airplanes of U.S. registry. We also estimate that it would take 
about 110 work-hours per engine to perform the proposed actions, and 
that the average labor rate is $80 per work-hour. Required parts would 
cost about $437,000 per engine. Based on these figures, we estimate the 
total cost of the proposed AD to U.S. operators to be $4,462,000.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify that the proposed AD:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979); and
    3. Would not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD. You may get a copy of this summary at the 
address listed under ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Under the authority delegated to me by the Administrator, the 
Federal Aviation Administration proposes to amend 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. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive:

General Electric Co. (GE): Docket No. FAA-2008-1206; Directorate 
Identifier 2008-NE-19-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by January 13, 
2009.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to GE CF6-80A, CF6-80A1, CF6-80A2, and CF6-
80A3 turbofan engines with a high-pressure turbine rotor (HPTR) 
stage 1 disk, part number (P/N) 9367M45G06, installed. These engines 
are installed on, but not limited to, Airbus A310 series and Boeing 
767 series airplanes.

[[Page 67435]]

Unsafe Condition

    (d) This AD results from an error by GE that incorrectly cited a 
cyclic life of 12,600 CSN in the Airworthiness Limitations Section 
(ALS) of the Instructions for Continued Airworthiness (ICA) for the 
HPTR, P/N 9367M45G06. We are issuing this AD to prevent the HPTR 
stage 1 disk from exceeding its part life which could cause fatigue 
cracks to start and grow. These cracks could result in a possible 
uncontained disk failure and damage to the airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified unless the 
actions have already been done.

New Reduced Life Limit for HPTR Stage 1 Disks, P/N 9367M45G06

    (f) After the effective date of this AD, remove HPTR stage 1 
disks, P/N 9367M45G06, from service before exceeding the new, 
reduced life limit of 2,075 cycles-since-new.

Alternative Methods of Compliance

    (g) The Manager, Engine Certification Office, has the authority 
to approve alternative methods of compliance for this AD if 
requested using the procedures found in 14 CFR 39.19.

Special Flight Permits

    (h) Under 14 CFR part 39.23, we are prohibiting any special 
flight permits.

Related Information

    (i) Contact Robert Green, Aerospace Engineer, Engine 
Certification Office, FAA, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
robert.green@faa.gov; telephone (781) 238-7754; fax (781) 238-7199, 
for more information about this AD.

    Issued in Burlington, Massachusetts, on November 7, 2008.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
 [FR Doc. E8-27080 Filed 11-13-08; 8:45 am]

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