Document ID: FAA-2017-0452-0003
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: General Electric Company Turboshaft Engines
Posted Date: 2017-09-22T04:00Z

[Federal Register Volume 82, Number 183 (Friday, September 22, 2017)]
[Rules and Regulations]
[Pages 44299-44301]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-19961]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-0452; Product Identifier 2017-NE-14-AD; Amendment 
39-19050; AD 2017-19-20]
RIN 2120-AA64

Airworthiness Directives; General Electric Company Turboshaft 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for certain 
General Electric Company (GE) CT7-8A and CT7-9B model turboshaft 
engines. This AD was prompted by reports from the manufacturer that the 
high-pressure compressor (HPC) impeller installed on these engines may 
have suffered from material degradation during the manufacturing 
process. This AD requires removal of the affected HPC impellers. We are 
issuing this AD to address the unsafe condition on these products.

DATES: This AD is effective October 27, 2017.

ADDRESSES: For service information identified in this final rule, 
contact General Electric Company, GE-Aviation, Room 285, 1 Neumann Way, 
Cincinnati, OH 45215; phone: 513-552-3272; fax: 513-552-3329; email: 
geae.aoc@ge.co. You may view this service information at the FAA, 
Engine and Propeller Standards Branch, 1200 District Avenue, 
Burlington, MA. For information on the availability of this material at 
the FAA, call 781-238-7125. It is also available on the internet at 
http://www.regulations.gov by searching for and locating Docket No. 
FAA-2017-0452.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-
0452; 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 final rule, the regulatory evaluation, any comments 
received, and other information. The address for the

[[Page 44300]]

Docket Office (phone: 800-647-5527) is Document Management Facility, 
U.S. Department of Transportation, Docket Operations, M-30, West 
Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., 
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Kasra Sharifi, Aerospace Engineer, ECO 
Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-
238-7773; fax: 781-238-7199; email: kasra.sharifi@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 by adding an AD that would apply to certain GE CT7-8A and CT7-
9B model turboshaft engines. The NPRM published in the Federal Register 
on June 16, 2017 (82 FR 27634). The NPRM was prompted by reports from 
the manufacturer that the HPC impeller installed on these engines may 
have suffered from material degradation during the manufacturing 
process. The NPRM proposed to require removal of the affected HPC 
impellers. We are issuing this AD to prevent failure of the HPC 
impeller, uncontained HPC impeller release, damage to the engine, and 
damage to the airplane/helicopter.

Comments

    We gave the public the opportunity to participate in developing 
this final rule. We received no comments on the NPRM or on the 
determination of the cost to the public.

Conclusion

    We reviewed the relevant data and determined that air safety and 
the public interest require adopting this final rule as proposed.

Related Service Information

    We reviewed GE Service Bulletin (SB) CT7-TP S/B 72-0524, dated June 
16, 2016. The SB describes procedures for replacing the affected HPC 
impellers.

Costs of Compliance

    We estimate that this AD affects 1 engine installed on a helicopter 
of U.S. registry.
    We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Replace HPC impeller..................  0 work-hours x $85 per           $70,000         $70,000         $70,000
                                         hour = $0.
----------------------------------------------------------------------------------------------------------------

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.
    This AD is issued in accordance with authority delegated by the 
Executive Director, Aircraft Certification Service, as authorized by 
FAA Order 8000.51C. In accordance with that order, issuance of ADs is 
normally a function of the Compliance and Airworthiness Division, but 
during this transition period, the Executive Director has delegated the 
authority to issue ADs applicable to engines, propellers, and 
appliances to the Manager, Engine and Propeller Standards Branch, 
Policy and Innovation Division.

Regulatory Findings

    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),
    (3) Will not affect intrastate aviation in Alaska to the extent 
that it justifies making a regulatory distinction, 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.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA 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 (AD):

2017-19-20 General Electric Company: Amendment 39-19050; Docket No. 
FAA-2017-0452; Product Identifier 2017-NE-14-AD.

(a) Effective Date

    This AD is effective October 27, 2017.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to General Electric Company (GE) CT7-8A and CT7-
9B model turboshaft engines with a high-pressure compressor (HPC) 
impeller, part number 5123T51P02, and serial number, GLHTPH9G, 
GLHTPP7P, or GLHTPJHN, installed.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7230, Turbine Engine 
Compressor Section.

(e) Unsafe Condition

    This AD was prompted by reports from the manufacturer that the 
HPC impeller installed on these engines may have suffered from 
material degradation during the manufacturing process. We are 
issuing this AD to prevent failure of the HPC impeller.

[[Page 44301]]

This unsafe condition, if not corrected, could result in failure of 
the HPC impeller, uncontained HPC impeller release, damage to the 
engine, and damage to the airplane/helicopter.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.
    (1) For CT7-9B engines, remove the affected HPC impeller from 
service at the next engine shop visit after the effective date of 
this AD, or prior to accumulating 12,000 cycles since new, whichever 
is earlier.
    (2) For CT7-8A engines, remove the affected HPC impeller from 
service at the next engine shop visit after the effective date of 
this AD, or prior to accumulating 1,500 engine hours after the 
effective date of this AD, whichever is earlier.

(g) Definition

    For the purpose of this AD, an ``engine shop visit'' is the 
induction of an engine into the shop for maintenance involving the 
separation of pairs of major mating engine flanges.

(h) Alternative Methods of Compliance (AMOCs)

    The Manager, Engine Certification Office, FAA, may approve AMOCs 
for this AD. Use the procedures found in 14 CFR 39.19 to make your 
request. You may email your request to: ANE-AD-AMOC@faa.gov.

(i) Related Information

    (1) For more information about this AD, contact Kasra Sharifi, 
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: 781-238-7773; fax: 781-238-7199; email: 
kasra.sharifi@faa.gov.
    (2) GE Service Bulletin CT7-TP S/B 72-0524, dated June 16, 2016, 
can be obtained from GE using the contact information in paragraph 
(i)(3) of this AD.
    (3) For service information identified in this AD, contact 
General Electric Company, GE-Aviation, Room 285, 1 Neumann Way, 
Cincinnati, OH 45215; phone: 513-552-3272; fax: 513-552-3329; email: 
geae.aoc@ge.com.
    (4) You may view this service information at the FAA, Engine and 
Propeller Standards Branch, 1200 District Avenue, Burlington, MA 
01803. For information on the availability of this material at the 
FAA, call 781-238-7125.

(j) Material Incorporated by Reference

    None.

    Issued in Burlington, Massachusetts, on September 13, 2017.
Robert J. Ganley,
Manager, Engine and Propeller Standards Branch, Aircraft Certification 
Service.
[FR Doc. 2017-19961 Filed 9-21-17; 8:45 am]
 BILLING CODE 4910-13-P