[Federal Register Volume 76, Number 91 (Wednesday, May 11, 2011)]
[Proposed Rules]
[Pages 27282-27284]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-11481]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2011-0187; Directorate Identifier 2011-NE-07-AD]
RIN 2120-AA64
Airworthiness Directives; General Electric Company CF34-10E2A1;
CF34-10E5, CF34-10E5A1; CF34-10E6; CF34-10E6A1; CF34-10E7; and CF34-
10E7-B Turbofan Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: We propose to adopt a new airworthiness directive (AD) for the
products listed above with certain part number (P/N) fan rotor spinners
[[Page 27283]]
installed. This proposed AD would require removing from service certain
fan rotor blade retainers, and removing from service the fan rotor
spinner support that was installed with those fan rotor blade
retainers. This proposed AD was prompted by a fan rotor spinner support
found cracked at the attachment lugs. We are proposing this AD to
prevent high-cycle fatigue cracking of the fan rotor spinner support
attachment lugs, leading to separation of the fan rotor spinner
assembly, uncontained failure of the engine, and damage to the
airplane.
DATES: We must receive comments on this proposed AD by June 27, 2011.
ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
Fax: 202-493-2251.
Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590.
Hand Delivery: Deliver to Mail address above between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
For service information identified in this proposed AD, contact GE-
Aviation, M/D Rm. 285, One Neumann Way, Cincinnati, OH 45215, telephone
513-552-3272; e-mail: [email protected]. You may review copies of the
referenced service information at the FAA, Engine & Propeller
Directorate, 12 New England Executive Park, Burlington, MA. For
information on the availability of this material at the FAA, call 781-
238-7125.
Examining the AD Docket
You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility
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 Office (phone: 800-647-5527) is in the ADDRESSES
section. Comments will be available in the AD docket shortly after
receipt.
FOR FURTHER INFORMATION CONTACT: John Frost, Aerospace Engineer, Engine
Certification Office, FAA, 12 New England Executive Park, Burlington,
MA 01803; phone: 781-238-7756; fax: 781-238-7199; e-mail:
[email protected].
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under the ADDRESSES section. Include ``Docket No. FAA-2011-0187;
Directorate Identifier 2011-NE-07-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of this proposed AD. We
will consider all comments received by the closing date and may amend
this proposed AD because 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 we
receive about this proposed AD.
Discussion
Investigation of a General Electric Company (GE) CF34-10E turbofan
engine experiencing high fan frame vibrations led to removal of the fan
rotor spinner. Eight of the twelve attachment lugs on the fan rotor
spinner support were found cracked. The cause of the vibration was
determined to be a non-synchronous vibration induced by a spinner
redesign that removed an interference between the fan blade retainers
and the spinner. This condition, if not corrected, could result in
high-cycle fatigue cracking of the fan rotor spinner support attachment
lugs, leading to separation of the fan rotor spinner assembly,
uncontained failure of the engine, and damage to the airplane.
Relevant Service Information
We reviewed GE Service Bulletin (SB) No. CF34-10E-S/B 72-0186,
dated January 31, 2011. The SB describes procedures for replacement of
the fan rotor blade retainers with redesigned retainers that
reintroduce the interference between the fan blade retainers and the
spinner. The SB also describes procedures for replacement of the fan
rotor spinner support, with a new support of the same P/N.
FAA's Determination
We are proposing this AD because we evaluated all the relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of the same type design.
Proposed AD Requirements
This proposed AD would require removing from service fan rotor
blade retainers, P/N 2050M56P02, and removing from service the fan
rotor spinner support that was installed with those fan rotor blade
retainers.
Costs of Compliance
We estimate that this proposed AD would affect 164 engines
installed on airplanes of U.S. registry. We also estimate that it would
take about 2 work-hours per engine to perform the actions required by
this proposed AD, and that the average labor rate is $85 per work-hour.
If all removed parts get replaced, required parts would cost about
$10,458 per engine. Based on these figures, we estimate the total cost
of the proposed AD to U.S. operators to be $1,742,992.
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 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 this proposed
regulation:
(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),
(3) Will not affect intrastate aviation in Alaska, and
(4) Will not have a significant economic impact, positive or
negative, on a substantial number of small entities
[[Page 27284]]
under the criteria of the Regulatory Flexibility Act.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA 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 (AD):
General Electric Company: Docket No. FAA-2011-0187; Directorate
Identifier 2011-NE-07-AD.
Comments Due Date
(a) We must receive comments by June 27, 2011.
Affected ADs
(b) None.
Applicability
(c) This AD applies to General Electric Company (GE) CF34-
10E2A1; CF34-10E5, CF34-10E5A1; CF34-10E6; CF34-10E6A1; CF34-10E7;
and CF34-10E7-B turbofan engines, with a fan rotor spinner part
number (P/N) 2050M34G03; 2050M34G04; 2050M34G05; 2050M34G06;
2437M60G01; or 2437M60G02, installed.
Unsafe Condition
(d) This AD was prompted by a fan rotor spinner support found
cracked at the attachment lugs. We are issuing this AD to prevent
high-cycle fatigue cracking of the fan rotor spinner support
attachment lugs, leading to separation of the fan rotor spinner
assembly, uncontained failure of the engine, and damage to the
airplane.
Compliance
(e) Comply with this AD within 1,800 hours-in-service after the
effective date of this AD, unless already done.
Removal of Fan Rotor Blade Retainers
(f) Remove from service the 24 fan rotor blade retainers, P/N
2050M56P02.
Removal of Fan Rotor Spinner Support
(g) Remove from service the fan rotor spinner support that
operated with the fan rotor blade retainers removed in paragraph (f)
of this AD.
Installation Prohibition
(h) After the effective date of this AD, do not install any fan
rotor blade retainer, P/N 2050M56P02, into any engine. Do not
attempt to repair, make serviceable, or re-install, this part.
(i) After the effective date of this AD, do not install any fan
rotor spinner support removed in paragraph (g) of this AD, into any
engine. Do not attempt to repair, make serviceable, or re-install,
this part.
Alternative Methods of Compliance (AMOCs)
(j) The Manager, Engine Certification Office, FAA, has the
authority to approve AMOCs for this AD, if requested using the
procedures found in 14 CFR 39.19.
Related Information
(k) For more information about this AD, contact John Frost,
Aerospace Engineer, Engine Certification Office, FAA, 12 New England
Executive Park, Burlington, MA 01803; phone: 781-238-7756; fax: 781-
238-7199; e-mail: [email protected].
(l) Refer to GE Service Bulletin No. CF34-10E-S/B 72-0186, dated
January 31, 2011, for related information. Contact GE-Aviation, M/D
Rm. 285, One Neumann Way, Cincinnati, OH 45215, telephone 513-552-
3272; e-mail: [email protected], for a copy of this service
information. You may review copies of the referenced service
information at the FAA, Engine & Propeller Directorate, 12 New
England Executive Park, Burlington, MA. For information on the
availability of this material at the FAA, call 781-238-7125.
Issued in Burlington, Massachusetts, on April 28, 2011.
Peter A. White,
Acting Manager, Engine & Propeller Directorate, Aircraft Certification
Service.
[FR Doc. 2011-11481 Filed 5-10-11; 8:45 am]
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