[Federal Register Volume 76, Number 102 (Thursday, May 26, 2011)]
[Proposed Rules]
[Pages 30573-30575]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-13013]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2011-0278; Directorate Identifier 2010-NE-10-AD]
RIN 2120-AA64
Airworthiness Directives; General Electric Company (GE) GE90-
110B1 and GE90-115B 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) high-pressure
compressor (HPC) stages 2-5 spools installed. This proposed AD would
require eddy current inspection (ECI) or spot fluorescent penetrant
inspection (FPI) of the stages 1-2 rotating seal teeth of the HPC
stages 2-5 spool for cracks and would prohibit installation of HPC
stator stage 1 interstage seals that are not pregrooved to prevent
heavy rubs. This proposed AD was prompted by an aborted takeoff and two
shop findings of cracks in the stages 1-2 rotating seal teeth. We are
proposing this AD to detect cracks in the HPC stages 1-2 rotating seal
teeth due to heavy rubs, which could result in failure of the stages 1-
2 rotating seal of the HPC
[[Page 30574]]
stages 2-5 spool, uncontained engine failure, and damage to the
airplane.
DATES: We must receive any comments on this proposed AD by July 11,
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
General Electric, GE-Aviation, Room 285, 1 Newman Way, Cincinnati, Ohio
45215; e-mail: [email protected]; phone: 513-552-3272; fax: 513-552-3329.
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: Jason Yang, Aerospace Engineer, Engine
Certification Office, FAA, Engine & Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803; phone: 781-238-7747; fax:
781-238-7199; e-mail: [email protected].
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send us 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-2011-0278;
Directorate Identifier 2010-NE-10-AD'' in the subject line 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
the 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
We received a report of an engine failure caused by the liberation
of a portion of the HPC stages 1-2 rotating seal teeth, and subsequent
reports of HPC stages 1-2 rotating seal teeth cracks, due to heavy
rubs, found in engines in the shop. The heavy rubs are due to
insufficient clearance between the rotating seal teeth and the
abradable coating on the static seal. This proposed AD would require
ECI or spot FPI of the stages 1-2 rotating seal teeth of the HPC stages
2-5 spool for cracks, and would prohibit installation of HPC stator
stage 1 interstage seals that are not pregrooved in order to prevent
heavy rubs. This condition, if not corrected, could result in failure
of the stages 1-2 rotating seal of the HPC stages 2-5 spool,
uncontained engine failure, and damage to the airplane.
Relevant Service Information
We reviewed GE Service Bulletin (SB) GE90-100 S/B 72-0320, Revision
02, dated October 1, 2010. That service information describes
procedures for inspecting the stages 1-2 seal teeth for cracks.
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 on other products of the same type design.
Proposed AD Requirements
This proposed AD would require accomplishing the actions specified
in the service information described previously.
Costs of Compliance
We estimate that this proposed AD would affect 19 GE90-110B1 and
GE90-115B engines installed on airplanes of U.S. registry. We also
estimate that it would take about 2 work-hours per engine to perform
the proposed actions, and that the average labor rate is $85 per work-
hour. Required parts would cost about $9,857 per engine. Based on these
figures, we estimate the total cost of the proposed AD to U.S.
operators to be $190,513.
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 that the 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 under the criteria
of the Regulatory Flexibility Act.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, 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:
[[Page 30575]]
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-2011-0278; Directorate
Identifier 2010-NE-10-AD.
Comments Due Date
(a) We must receive comments by July 11, 2011.
Affected ADs
(b) None.
Applicability
(c) This AD applies to General Electric Company (GE) GE90-110B1
and GE90-115B turbofan engines with high-pressure compressor (HPC)
stages 2-5 spools, part numbers (P/Ns) 351-103-106-0, 351-103-107-0,
351-103-108-0, 351-103-109-0, 351-103-141-0, 351-103-142-0, 351-103-
143-0 and 351-103-144-0, installed.
Unsafe Condition
(d) This AD was prompted by an aborted takeoff and two shop
findings of cracks in the stages 1-2 rotating seal teeth. We are
issuing this AD to detect cracks in the HPC stages 1-2 rotating seal
teeth due to heavy rubs, which could result in failure of the stages
1-2 rotating seal of the HPC stages 2-5 spool, uncontained engine
failure, and damage to the airplane.
Compliance
(e) Comply with this AD when the HPC forward case half is
removed from the engine after the effective date of this AD, unless
the actions have already been done.
Inspection
(f) Perform an eddy current inspection or a fluorescent
penetrant inspection of the stage 1-2 seal teeth using paragraphs
3.B. or 3.C. of GE Service Bulletin (SB) GE90-100 S/B 72-0320,
Revision 02, dated October 1, 2010.
Disposition of Spools with Cracked Seal Teeth
(g) If you find cracks, remove the HPC stages 2-5 spool from
service.
Previous Credit
(h) An inspection performed before the effective date of this AD
using SB GE90-100 S/B 72-0320 Revision 01, dated May 11, 2010, or
earlier revision, satisfies the inspection requirement of this AD.
Installation Prohibition
(i) After the effective date of this AD, do not install any HPC
forward case unless it has an HPC stator stage 1 interstage seals,
P/N 351-109-503-0.
Alternative Methods of Compliance (AMOCs)
(j) The Manager, Engine Certification Office, has the authority
to approve AMOCs for this AD if requested using the procedures found
in 14 CFR 39.19.
Related Information
(k) Contact Jason Yang, Aerospace Engineer, Engine Certification
Office, FAA, Engine & Propeller Directorate, 12 New England
Executive Park, Burlington, MA 01803; phone: 781-238-7747; fax: 781-
238-7199; e-mail: [email protected], for more information about
this AD.
(l) GE Service Bulletin GE90-100 S/B 72-0320, Revision 02, dated
October 1, 2010, pertain to the subject of this AD. Contact General
Electric, GE-Aviation, Room 285, 1 Newman Way, Cincinnati, Ohio
45215; e-mail: [email protected]; phone: 513-552-3272; fax: 513-552-
3329, for a copy of this service information.
Issued in Burlington, Massachusetts, on May 20, 2011.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 2011-13013 Filed 5-25-11; 8:45 am]
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