[Federal Register Volume 75, Number 202 (Wednesday, October 20, 2010)]
[Proposed Rules]
[Pages 64681-64683]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-26312]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2010-0998; Directorate Identifier 2010-NE-29-AD]
RIN 2120-AA64
Airworthiness Directives; General Electric Company (GE) CF6-45
Series and CF6-50 Series Turbofan Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for GE CF6-45 and CF6-50 series turbofan engines. This proposed AD
would require performing a fluorescent penetrant inspection (FPI) of
the stage 3 low-pressure turbine (LPT) rotor at every shop visit at
which the LPT module is separated from the engine. This proposed AD
results from seven
[[Page 64682]]
reports of uncontained failures of LPT stage 3 disks and eight reports
of cracked LPT stage 3 disks found during shop visit inspections. We
are proposing this AD to prevent LPT rotor separation, which could
result in an uncontained engine failure and damage to the airplane.
DATES: We must receive any comments on this proposed AD by December 20,
2010.
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.
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: Christopher J. Richards, Aerospace
Engineer, Engine Certification Office, FAA, Engine & Propeller
Directorate, 12 New England Executive Park, Burlington, MA 01803; e-
mail: [email protected]; phone: (781) 238-7133; 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-2010-0998; Directorate
Identifier 2010-NE-29-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
Since July 2008, we have received seven reports of uncontained
failures of LPT stage 3 rotor disks and eight reports of cracked LPT
rotor stage 3 disks found during shop visit inspections. Our
investigation revealed that certain part number LPT stage 3 rotor disks
might fail due to circumferential cracking of the forward cone body
(forward spacer arm) of the LPT stage 3 disk when exposed to core
engine (N2) vibrations. On June 4, 2010, we issued AD 2010-12-10 that
requires a separate set of corrective actions. Those actions, along
with this proposed AD, reduce the likelihood of further uncontained
engine failures. This condition, if not corrected, could result in
critical life-limited rotating engine part failure, which could result
in an uncontained engine 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
performing a fluorescent penetrant inspection at every shop visit when
the LPT module is separated from the engine.
Interim Action
These actions are interim actions and we may take further
rulemaking actions in the future.
Costs of Compliance
We estimate that this proposed AD would affect 387 engines
installed on airplanes of U.S. registry. We also estimate that it would
take about 7 work-hours per engine to perform the proposed actions, and
that the average labor rate is $85 per work-hour. No parts would be
required. Based on these figures, we estimate the total cost of the
proposed AD to U.S. operators to be $230,265.
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
[[Page 64683]]
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 Company: Docket No. FAA-2010-0998; Directorate
Identifier 2010-NE-29-AD.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive
comments on this airworthiness directive (AD) action by December 20,
2010.
Affected ADs
(b) None.
Applicability
(c) This AD applies to General Electric Company (GE) CF6-45A,
CF6-45A2, CF6-50A, CF6-50C, CF6-50CA, CF6-50C1, CF6-50C2, CF6-50C2B,
CF6-50C2D, CF6-50C2-F, CF6-50C2-R, CF6-50E, CF6-50E1, and CF6-50E2
series turbofan engines, with a low-pressure turbine (LPT) rotor
stage 3 disk that has a part number (P/N) listed in Table 1 of this
AD installed:
Table 1--LPT Rotor Stage 3 Disk P/Ns
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1473M90P01 1473M90P02 1473M90P03 1473M90P04
1479M75P01 1479M75P02 1479M75P03 1479M75P04
1479M75P05 1479M75P06 1479M75P07 1479M75P08
1479M75P09 1479M75P11 1479M75P13 1479M75P14
9061M23P06 9061M23P07 9061M23P08 9061M23P09
9061M23P10 9061M23P12 9061M23P14 9061M23P15
9061M23P16 9224M75P01
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These engines are installed on, but not limited to, Boeing 747-
200B series, -200C series, and -200F series, 747-300 series
airplanes; McDonnell Douglas DC-10-15, -30, and -30F, MD-10-30, KC-
10A, and KDC-10 airplanes; and Airbus A300 series airplanes.
Unsafe Condition
(d) This AD results from seven reports of uncontained failures
of LPT stage 3 disks and eight reports of cracked LPT stage 3 disks
found during shop visit inspections. We are issuing this AD to
prevent LPT rotor separation, which could result in an uncontained
engine failure and damage to the airplane.
Compliance
(e) You are responsible for having the actions required by this
AD performed at each shop visit after the effective date of this AD,
at which the LPT module is separated from the engine.
Cleaning the LPT Stage 3 Disk
(f) Clean the LPT stage 3 disk, using a wet-abrasive blast to
eliminate residual or background fluorescence. You can find guidance
on cleaning the disk in the cleaning procedure of CF6-50 Engine
Manual, GEK 50481 72-57-02.
Inspecting the LPT Stage 3 Disk
(g) Perform a fluorescent penetrant inspection (FPI) of the
inner diameter of the forward cone body (forward spacer arm) of the
LPT stage 3 disk. You can find guidance on performing the FPI in the
CF6-50 Engine Manual, GEK 50481 72-57-02.
(h) If a crack or a band of fluorescence is present, remove the
disk from service.
Alternative Methods of Compliance
(i) 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.
Related Information
(j) Contact Christopher J. Richards, Aerospace Engineer, Engine
Certification Office, FAA, Engine & Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803; e-mail:
[email protected]; phone: (781) 238-7133; fax: (781)
238-7199, for more information about this AD.
Issued in Burlington, Massachusetts, on October 8, 2010.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 2010-26312 Filed 10-19-10; 8:45 am]
BILLING CODE 4910-13-P