Document ID: FAA-2010-0732-0001
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: General Electric Co. (GE) CT7-9C and -9C3 Turboprop Engines
Posted Date: 2010-07-23T04:00Z

[Federal Register Volume 75, Number 141 (Friday, July 23, 2010)]
[Proposed Rules]
[Pages 43099-43101]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-17999]

-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0732; Directorate Identifier 2010-NE-04-AD]
RIN 2120-AA64

Airworthiness Directives; General Electric Company (GE) CT7-9C 
and -9C3 Turboprop Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for GE CT7-9C and -9C3 turboprop engines with certain serial number (S/
N) gas generator turbine (GGT) shafts, part number (P/N) 6068T44P02, 
installed. This proposed AD would require inspecting the GGT shaft for 
nonconforming land balance-cuts, and if found, removing the shaft from 
service. This proposed AD results from reports of a manufacturing 
quality problem. We are proposing this AD to detect nonconforming GGT 
shaft land balance-cuts, which could result in the shaft failing before 
its published life limit, and which could result in an uncontained 
engine failure and damage to the airplane.

DATES: We must receive any comments on this proposed AD by September 
21, 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.
    Contact General Electric Company, GE-Aviation, Room 285, 1 Newmann 
Way, Cincinnati, Ohio 45215; e-mail geae.aoc@ge.com; telephone (513) 
552-3272; fax (513) 552-3329, for a copy of the service information 
identified in this proposed AD.

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: 

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-2010-0732; Directorate 
Identifier 2010-NE-04-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,

[[Page 43100]]

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

    We have received reports of 21 nonconforming land balance-cuts on 
GGT shafts, P/N 6068T44P02. The nonconforming land balance-cuts can 
negatively affect the low-cycle fatigue life capability of the shaft. 
This condition, if not corrected, could result in the shaft failing 
before its published life limit, and which could result in an 
uncontained engine failure and damage to the airplane.

Relevant Service Information

    We have reviewed and approved the technical contents of GE CT7-TP 
Alert Service Bulletin (ASB) 72-A0501, Revision 01, dated March 3, 
2010, that lists the affected shafts by P/N and S/N, and describes 
procedures for inspecting the GGT shaft for nonconforming land balance-
cuts.

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 
inspecting certain S/N GGT shafts, P/N 6068T44P02, for nonconforming 
land balance-cuts, and if found, replacing the shaft. The proposed AD 
would require you to use the service information described previously 
to perform these actions.

Costs of Compliance

    We estimate that this proposed AD would affect five engines 
installed on airplanes of U.S. registry. We also estimate that it would 
take about 1 work-hour per engine to perform the inspection, 1.5 work-
hours to replace the shaft, and that the average labor rate is $85 per 
work-hour. Required parts would cost about $28,633 per engine. Based on 
these figures, we estimate the total cost of the proposed AD to U.S. 
operators to be $144,227.

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, Incorporation by 
reference, Safety.

The Proposed Amendment

    Under the authority delegated to me by the Administrator, the 
Federal 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 (GE): Docket No. FAA-2010-0732; Directorate 
Identifier 2010-NE-04-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by September 
21, 2010.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to GE CT7-9C and -9C3 turboprop engines with 
gas generator turbine (GGT) shafts, part number (P/N) 6068T44P02, 
that have a serial number (S/N) listed in Table 1 of this AD, 
installed. These engines are installed on, but not limited to, EADS 
CASA (formerly Construcciones Aeronauticas, S.A.) CN-235 series 
airplanes.

                    Table 1--Affected GGT Shaft S/Ns
------------------------------------------------------------------------
 
------------------------------------------------------------------------
                           Affected Shaft S/Ns
------------------------------------------------------------------------
GATHHCPC           GATHHJR7           GATHHJR9          GATHHKG6
GATHHM9R           GATHHWM3           GATHJ4ED          GATHJ9FL
GATHJ19J           GATHJE8P           GATHJWWR          GATHK0KM
GATHK2N1           GATHK3M3           GATHK90K          GATHK96D
GATHKF9R           GATHKH36           GATHKMP7          GATHKRKN
NCE715DA           .................  ................  ................
------------------------------------------------------------------------

[[Page 43101]]

Unsafe Condition

    (d) This AD results from reports of a manufacturing quality 
problem. We are issuing this AD to detect nonconforming GGT shaft 
land balance-cuts, which could result in the shaft failing before 
its published life limit, and 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 the first shop visit after the effective date of 
this AD, or within 5,000 cycles-since-new, whichever occurs first, 
unless the actions have already been done.

Inspection for Nonconforming Land Balance-Cuts

    (f) For CT7-9C and -9C3 engines with a GGT shaft, P/N 
6068T44P02, that has a S/N listed in Table 1 of this AD, installed, 
inspect the shaft for nonconforming land balance-cuts. Use the 
Accomplishment Instructions 3.A.(1) through 3.A.(4) of GE CT7-TP 
Alert Service Bulletin 72-A0501, Revision 01, dated March 3, 2010, 
to perform the inspection.
    (g) If you find any nonconforming land balance-cuts, remove the 
shaft from service.

Alternative Methods of Compliance

    (h) 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

    (i) 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.
    (j) GE CT7-TP Alert Service Bulletin 72-A0501, Revision 01, 
dated March 3, 2010, pertains to the subject of this AD. Contact 
General Electric Company, GE-Aviation, Room 285, 1 Newmann Way, 
Cincinnati, Ohio 45215; e-mail geae.aoc@ge.com; telephone (513) 552-
3272; fax (513) 552-3329, for a copy of this service information.

    Issued in Burlington, Massachusetts, on July 15, 2010.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2010-17999 Filed 7-22-10; 8:45 am]
BILLING CODE 4910-13-P