Document ID: FAA-2009-0143-0008
Agency: faa
Document Type: Rule
Title: Airworthiness Directives; General Electric Company GE90-110B1, GE90-113B, and GE90-115B Series Turbofan Engines
Posted Date: 2009-12-14T05:00Z

[Federal Register: December 14, 2009 (Volume 74, Number 238)]
[Rules and Regulations]               
[Page 66042-66045]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr14de09-7]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2009-0143; Directorate Identifier 2009-NE-05-AD; 
Amendment 39-16135; AD 2009-25-14]
RIN 2120-AA64

 
Airworthiness Directives; General Electric Company GE90-110B1, 
GE90-113B, and GE90-115B Series Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
General Electric Company (GE) GE90-110B1, GE90-113B, and GE90-115B 
series turbofan engines with stage 6 low-pressure turbine (LPT) blades, 
part number (P/N) 1765M37P03 or P/N

[[Page 66043]]

1765M37P04, installed. This AD requires initial and repetitive 
inspections for shroud interlock wear of the stage 6 LPT blades. This 
AD also requires replacing those blades with stage 6 LPT blades 
eligible for installation at the next engine shop visit as terminating 
action to the repetitive blade inspections. This AD results from eight 
reports of GE90-115B stage 6 LPT single-blade separation events. We are 
issuing this AD to prevent failure of stage 6 LPT blades, which could 
result in uncontained engine failure and damage to the airplane.

DATES: This AD becomes effective January 19, 2010. The Director of the 
Federal Register approved the incorporation by reference of certain 
publications listed in the regulations as of January 19, 2010.

ADDRESSES: You can get the service information identified in this AD 
from General Electric Company via GE-Aviation, Attn: Distributions, 111 
Merchant St., Room 230, Cincinnati, Ohio 45246; telephone (513) 552-
3272; fax (513) 552-3329.
    The Docket Operations office is located at Docket Management 
Facility, U.S. Department of Transportation, 1200 New Jersey Avenue, 
SE., West Building Ground Floor, Room W12-140, Washington, DC 20590-
0001.

FOR FURTHER INFORMATION CONTACT: Barbara Caufield, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; e-mail: 
barbara.caufield@faa.gov; telephone (781) 238-7146; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39 
with a proposed AD. The proposed AD applies to GE GE90-110B1, GE90-
113B, and GE90-115B series turbofan engines with stage 6 LPT blades, P/
N 1765M37P03 or P/N 1765M37P04, installed. We published the proposed AD 
in the Federal Register on June 24, 2009 (74 FR 30020). That action 
proposed to require initial and repetitive inspections for shroud 
interlock wear of the stage 6 LPT blades. That action also proposed to 
require replacing those blades with stage 6 LPT blades eligible for 
installation at the next engine shop visit as terminating action to the 
repetitive blade inspections.

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 provided in 
the ADDRESSES section. Comments will be available in the AD docket 
shortly after receipt.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments received.

Request To Include Service Bulletin (SB) Revision 3

    One commenter, All Nippon Airways, requests that we include GE SB 
No. GE90-100 SB 72-0260, Revision 3, dated July 17, 2008, in Previous 
Credit paragraph (i).
    We do not agree. That SB does not specifically call out the need to 
inspect engines with replacement, original configuration, stage 6 LPT 
blades. We did not change the AD.

Request To Correct SB Paragraph References

    All Nippon Airways and Japan Airlines requests that in paragraph 
(f), we correct the reference of what paragraphs to use in the SB, from 
``3.A through 3.A.(3)(g)(12)'', to ``3.A through 3.A.(2)(g)(12)''.
    We agree the reference needs correcting. We made the correction, 
but listed the latest revision of the SB, which is GE SB No. GE90-100 
SB 72-0260, Revision 7, dated June 2, 2009. We also added SB No. GE90-
100 SB 72-0260, Revision 6, dated May 1, 2009, to the Previous Credit 
paragraph.

Requests To Change the Unsafe Condition Paragraph (d)

    GE Aviation requests that we change the Unsafe Condition paragraph 
(d) to state that, in each case, the engine continued to produce 
commanded thrust.
    We do not agree. Although the statement is true, adding it would 
lessen the impact of, and detract from, the existing unsafe condition 
statement. We did not change the AD.
    Boeing requests that we change the Unsafe Condition paragraph (d) 
to also state that there is a remote possibility of the unsafe 
condition event occurring on both engines on a given flight.
    We do not agree. We considered the possibility of a dual-engine 
failure event during our safety analysis and when determining the 
appropriate compliance actions for this AD. We did not change the AD.

Request To Reference the Latest GE SB Revision

    GE Aviation, Japan Airlines, and Eva Air request that we reference 
using latest GE SB in the AD, which is SB No. GE90-100 SB 72-0260, 
Revision 7, dated June 2, 2009.
    We agree and have referenced the use of Revision 7 in the AD.

Request To Reference the Use of Later-FAA-Approved SB Revisions

    One commenter, V Australia, requests that we state to use ``or 
later-FAA-approved revision of the SB'' in the AD. The commenter states 
that Revision 7 has been issued since the proposed AD was issued, and 
it is likely that GE will issue more revisions.
    We do not agree. Rulemaking requirements do not permit advance 
approval of unknown future revisions to service bulletins. We did not 
change the AD.

Request To Add SB Revision 6 to Previous Credit Paragraph (i)

    GE Aviation and Japan Airlines request that we add GE SB No. GE90-
100 SB 72-0260, Revision 6, dated May 1, 2009, to the list of SB 
revisions in the Previous Credit paragraph (i).
    We agree and added SB Revision 6 to that paragraph.

Request for Change in Definition Paragraph (j)

    Japan Airlines requests that we change the Definition paragraph (j) 
to exclude the induction of engines into the shop for maintenance 
action that can be performed at line maintenance, but which is 
performed in the shop for operator convenience. The commenter states 
that making this change will help eliminate an unnecessary burden to 
the operators.
    We do not agree. The existing engine shop visit definition is 
intended to lead operators to perform the terminating action as soon as 
possible. Doing this will reduce the reliance upon repetitive 
inspections and continued risk of blade failure. We did not change the 
AD.

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

    We estimate that this AD will affect four GE GE90-110B1, GE90-113B, 
and

[[Page 66044]]

GE90-115B series engines installed on airplanes of U.S. registry. We 
also estimate that it will take about 18 work-hours per engine to 
perform one inspection of the stage 6 LPT blades, and that the average 
labor rate is $80 per work-hour. Replacement stage 6 LPT blades will 
cost $258,280 per engine. We estimate that no additional labor costs 
will be incurred to perform the required blade replacements, because 
the replacements will be done during a scheduled engine shop visit. 
Based on these figures, we estimate the total cost of the AD for one 
inspection to U.S. operators to be $1,038,880.

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 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, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the Federal Aviation Administration amends 14 CFR part 39 as follows:

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:

2009-25-14 General Electric Company: Amendment 39-16135. Docket No. 
FAA-2009-0143; Directorate Identifier 2009-NE-05-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective January 
19, 2010.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to General Electric Company (GE) GE90-110B1, 
GE90-113B, and GE90-115B series turbofan engines with stage 6 low-
pressure turbine (LPT) blades, part number (P/N) 1765M37P03 or P/N 
1765M37P04, installed. These engines are installed on, but not 
limited to, Boeing 777-200LR, 777-300ER, and 777 Freighter series 
airplanes.

Unsafe Condition

    (d) This AD results from eight reports of GE90-115B stage 6 LPT 
single-blade separation events. We are issuing this AD to prevent 
failure of stage 6 LPT blades, which could result in 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.

Inspections

    (f) Before accumulating 3,000 engine operating hours time-since-
new, or 400 engine cycles-since-new, whichever occurs first, inspect 
the stage 6 LPT blades, P/N 1765M37P03 or P/N 1765M37P04 for shroud 
interlock wear. Thereafter, re-inspect within every 1,000 engine 
operating hours, or within 125 engine cycles-since-last inspection, 
whichever occurs first. Use paragraphs 3.A. through 3.A.(2)(g)(12) 
of the Accomplishment Instructions of GE Service Bulletin (SB) No. 
GE90-100 SB 72-0260, Revision 7, dated June 2, 2009, to do both the 
initial and repetitive inspections.

Terminating Action

    (g) At the next engine shop visit, replace the stage 6 LPT 
blades, P/N 1765M37P03 or P/N 1765M37P04, with stage 6 LPT blades 
eligible for installation as terminating action to the repetitive 
inspections required by this AD.

Installation Prohibition of Affected Stage 6 LPT Blades

    (h) After the effective date of this AD, do not install any 
stage 6 LPT blades, P/N 1765M37P03 or P/N 1765M37P04, onto any 
engine.

Previous Credit

    (i) An inspection performed before the effective date of this AD 
using GE SB No. GE90-100 SB 72-0260, Revision 4, dated October 8, 
2008, or Revision 5, dated November 7, 2008, or Revision 6, dated 
May 1, 2009, satisfies the initial inspection requirement of this 
AD.

Definition

    (j) For the purpose of this AD, an engine shop visit is 
induction of the engine into the shop for any cause.

Alternative Methods of Compliance

    (k) 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

    (l) Contact Barbara Caufield, Aerospace Engineer, Engine 
Certification Office, FAA, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
barbara.caufield@faa.gov; telephone (781) 238-7146; fax (781) 238-
7199, for more information about this AD.
    (m) Guidance on determining which stage 6 LPT blades are 
eligible for installation can be found in GE Service Bulletin No. 
72-0279, Revision 1, dated December 11, 2008, and GE Service 
Bulletin No. 72-0313, dated March 18, 2009.

Material Incorporated by Reference

    (n) You must use GE Service Bulletin No. GE90-100 SB 72-0260, 
Revision 7, dated June 2, 2009, to perform the inspections required 
by this AD. The Director of the Federal Register approved the 
incorporation by reference of this service bulletin in accordance 
with 5 U.S.C. 552(a) and 1 CFR part 51. Contact General Electric 
Company via GE-Aviation, Attn: Distributions, 111 Merchant St., Room 
230, Cincinnati, Ohio 45246; telephone (513) 552-3272; fax (513) 
552-3329, for a copy of this service information. You may review 
copies at the FAA, New England Region, 12 New England Executive 
Park, Burlington, MA; or at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at NARA, call 202-741-6030, or go to: http://
www.archives.gov/federal-register/cfr/ibr-locations.html.

[[Page 66045]]

    Issued in Burlington, Massachusetts, on December 4, 2009.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. E9-29428 Filed 12-11-09; 8:45 am]

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