[Federal Register Volume 75, Number 51 (Wednesday, March 17, 2010)]
[Rules and Regulations]
[Pages 12661-12663]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-5777]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2010-0068; Directorate Identifier 2010-NE-05-AD;
Amendment 39-16240; AD 2010-06-15]
RIN 2120-AA64
Airworthiness Directives; General Electric Company CF6-45 and
CF6-50 Series Turbofan Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
General Electric Company (GE) CF6-45 and CF6-50 series turbofan engines
with certain low-pressure turbine (LPT) stage 3 disks installed. This
AD requires fluorescent penetrant inspection (FPI) of the LPT stage 3
disk under certain conditions and removal of the disk from service
before further flight if found cracked. This AD also requires initial
and repetitive borescope inspections of the high-pressure turbine (HPT)
rotor stage 1 and stage 2 blades for wear and damage, including
excessive airfoil material loss. This AD results from three 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 critical life-limited rotating engine part failure,
which could result in an uncontained engine failure and damage to the
airplane.
DATES: This AD becomes effective April 1, 2010.
[[Page 12662]]
We must receive any comments on this AD by May 17, 2010.
ADDRESSES: Use one of the following addresses to comment on this AD:
Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the instructions for sending your
comments electronically.
Mail: U.S. Docket Management Facility, 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]; telephone (781) 238-7133; fax
(781) 238-7199.
SUPPLEMENTARY INFORMATION: Since July 2008, we received three 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. GE
reports that these failures were caused by HPT rotor blade airfoil
material loss which leads to LPT rotor unbalance, vibration, and LPT
disk separation. GE's investigation also revealed that certain part
number LPT stage 3 rotor disks could have micro-cracking on the inner
diameter surface forward cone body (forward spacer arm) that, when
exposed to rotor unbalance and other conditions, would allow crack
growth and disk failure. 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 This AD
The unsafe condition described previously is likely to exist or
develop on other GE CF6-45 and CF6-50 series turbofan engines of the
same type design. For that reason, we are issuing this AD to prevent
critical life-limited rotating engine part failure, which could result
in an uncontained engine failure and damage to the airplane. This AD
requires FPI of the LPT stage 3 disk under the conditions described
previously and permanent removal from service of the disk before
further flight if found cracked. This AD also requires an initial
borescope inspection of the HPT rotor for evidence of stage 1 and stage
2 blade excessive airfoil material loss, within 50 cycles-in-service
(CIS) after the effective date of this AD, and thereafter repetitive
borescope inspections within every 175 CIS.
FAA's Determination of the Effective Date
Since an unsafe condition exists that requires the immediate
adoption of this AD, we have found that notice and opportunity for
public comment before issuing this AD are impracticable, and that good
cause exists for making this amendment effective in less than 30 days.
Interim Action
These actions are interim actions and we may take further
rulemaking actions in the future.
Comments Invited
This AD is a final rule that involves requirements affecting flight
safety and was not preceded by notice and an opportunity for public
comment; however, we invite you to send us any written relevant data,
views, or arguments regarding this AD. Send your comments to an address
listed under ADDRESSES. Include ``AD Docket No. FAA-2010-0068;
Directorate Identifier 2010-NE-05-AD'' in the subject line of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify it.
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 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 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.
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 AD will not have federalism
implications under Executive Order 13132. This AD will 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 this 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. Will 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 summary of the costs to comply with this AD and
placed it in the AD Docket. 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.
Adoption of the Amendment
0
Under 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:
[[Page 12663]]
PART 39--AIRWORTHINESS DIRECTIVES
0
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]
0
2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive:
2010-06-15 General Electric Company: Amendment 39-16240. Docket No.
FAA-2010-0068; Directorate Identifier 2010-NE-05-AD.
Effective Date
(a) This airworthiness directive (AD) becomes effective April 1,
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, CF6-50C2F, CF6-50C2R, CF6-50E, CF6-50E1, and CF6-50E2,
series turbofan engines, with any of the following low-pressure
turbine (LPT) stage 3 disks installed:
------------------------------------------------------------------------
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9061M23P06 9061M23P07 9061M23P08 9061M23P09 9224M75P01
9061M23P10 1473M90P01 1473M90P02 1473M90P03 1473M90P04
9061M23P12 9061M23P14 9061M23P15 9061M23P16 1479M75P01
1479M75P02 1479M75P03 1479M75P04 1479M75P05 1479M75P06
1479M75P07 1479M75P08 1479M75P09 1479M75P11 1479M75P13
1479M75P14 N/A N/A N/A N/A
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These engines are installed on, but not limited to, Airbus A300
series, Boeing 747 series, McDonnell Douglas DC-10 series, and DC-
10-30F (KDC-10) airplanes.
Unsafe Condition
(d) This AD results from three 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 critical life-limited rotating engine part failure, 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 within the compliance times specified unless the
actions have already been done.
Borescope Inspection of High-Pressure Turbine (HPT) Stage 1 and Stage 2
Rotor Blades
(f) Within 50 cycles-in-service (CIS) after the effective date
of this AD, borescope-inspect the HPT stage 1 and stage 2 rotor
blades for wear and damage, including excessive airfoil material
loss.
(g) Thereafter, within every 175 CIS, repetitively borescope-
inspect the HPT stage 1 and stage 2 rotor blades for wear and
damage, including excessive airfoil material loss.
Actions Required Whenever the HPT Rotor Blade Cumulative Airfoil
Material Loss is 50% of a Blade or More
(h) Whenever the HPT rotor blade cumulative airfoil material
loss is 50% of a blade or more, then before further flight,
fluorescent penetrant inspect the inner diameter surface forward
cone body (forward spacer arm) of the LPT stage 3 disk.
(i) If the LPT stage 3 disk is cracked or if a circumferential
band of fluorescence appears, permanently remove the disk from
service.
Alternative Methods of Compliance
(j) 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
(k) 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]; telephone (781) 238-7133; fax (781)
238-7199, for more information about this AD.
Material Incorporated by Reference
(l) None.
Issued in Burlington, Massachusetts on March 10, 2010.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 2010-5777 Filed 3-16-10; 8:45 am]
BILLING CODE 4910-13-P