Document ID: FAA-2017-0943-0001
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: General Electric Company Turboprop Engines
Posted Date: 2018-02-13T05:00Z

[Federal Register Volume 83, Number 30 (Tuesday, February 13, 2018)]
[Rules and Regulations]
[Pages 6125-6127]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-02917]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-0943; Product Identifier 2017-NE-34-AD; Amendment 
39-19186; AD 2018-03-13]
RIN 2120-AA64

Airworthiness Directives; General Electric Company Turboprop 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: We are adopting a new airworthiness directive (AD) for certain 
General Electric Company (GE) CT7-5A2, CT7-5A3, CT7-7A, CT7-7A1, CT7-
9B, CT7-9B1, CT7-9B2, CT7-9C and CT7-9C3 model turboprop engines. This 
AD requires initial and repetitive visual inspection and fluorescent-
penetrant inspection (FPI) of the main propeller shaft. This AD was 
prompted by the failure of a main propeller shaft. We are issuing this 
AD to address the unsafe condition on these products.

DATES: This AD is effective February 28, 2018.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of February 28, 
2018.
    We must receive comments on this AD by March 30, 2018.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, 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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    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: 
[email protected]. 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 781-238-7759. It is also available on the 
internet at http://www.regulations.gov by searching for and locating 
Docket No. FAA-2017-0943.

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-
0943; 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 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: Michael Richardson-Bach, Aerospace 
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; 
phone: 781-238-7747; fax: 781-238-7199; email: [email protected].

SUPPLEMENTARY INFORMATION:

Discussion

    We received a report that a condition was found after an incident 
where the main propeller shaft on a GE CT7-9B failed in flight, 
resulting in the loss of the propeller. The condition is cracking 
initiating from undiscovered corrosion in the dowel pin hole on the 
flange of the main propeller shaft. This proposed AD would require 
visually inspecting the main propeller shaft for wear and corrosion and 
FPI for cracks. This condition, if not addressed, could result in 
failure of the main propeller shaft, resulting in in-flight loss of the 
propeller, loss of engine thrust control, and damage to the airplane. 
We are issuing this AD to address the unsafe condition on these 
products.
    A similar propeller separation incident occurred in 1992 because of 
a material defect. The affected parts were purged from the field at 
that time.

Related Service Information Under 1 CFR Part 51

    We reviewed SPM 70-32-03, SPOT-FLUORESCENT PENETRANT INSPECTION, 
TASK 70-32-03-230-002, from the GE Commercial Engine Standard Practices 
Manual GEK 9250, Rev. 106, dated April 01, 2007. This procedure 
provides instruction for spot FPI.
    We also reviewed MM 72-10-00, PROPELLER GEARBOX INSPECTION and MM 
72-10-00, PROPELLER GEARBOX--CLEANING, from the GE CT7B Maintenance 
Manual SEI-576, Rev. 60, dated October 1, 2017. These procedures 
provides instructions for inspection and cleaning, respectively, of the 
main propeller shaft.
    This service information is reasonably available because the 
interested parties have access to it through their normal course of 
business or by the means identified in the ADDRESSES section.

Other Related Service Information

    We reviewed GE Service Bulletin (SB) CT7-TP S/B 72-0531, dated June 
22, 2017. The SB references standard procedures for initial and 
repetitive visual and FPI of the main propeller shaft for SF340 
aircraft.
    We also reviewed GE SB CT7-TP S/B 72-0533, dated October 3, 2017. 
The SB references standard procedures for initial and repetitive visual 
and FPI

[[Page 6126]]

of the main propeller shaft for CN235 aircraft.

FAA's Determination

    We are issuing 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.

AD Requirements

    This AD requires visually inspecting the main propeller shaft for 
wear and corrosion and FPI for cracks.

Differences Between This AD and the Service Information

    The inspection plan in this AD adds visual inspection and FPI to 
the repetitive inspections. This AD adds upper limits to the ``inspect 
within'' times to avoid conflicting times to inspect.

FAA's Justification and Determination of the Effective Date

    An unsafe condition exists that requires the immediate adoption of 
this AD without providing an opportunity for public comments prior to 
adoption. The FAA has found that the risk to the flying public 
justifies waiving notice and comment prior to adoption of this rule 
because the compliance time for the action is less than the time 
required for public comment. Therefore, we find that notice and 
opportunity for prior public comment are impracticable. In addition, 
for the reason stated above, we find that good cause exists for making 
this amendment effective in less than 30 days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety and was not preceded by notice and an opportunity for public 
comment. However, we invite you to send any written data, views, or 
arguments about this final rule. Send your comments to an address 
listed under the ADDRESSES section. Include the docket number Docket 
No. FAA-2017-0943 and Product Identifier 2017-NE-34-AD at the beginning 
of your comments. We specifically invite comments on the overall 
regulatory, economic, environmental, and energy aspects of this final 
rule. We will consider all comments received by the closing date and 
may amend this final rule 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 final rule.

Costs of Compliance

    We estimate that this AD affects 176 engines installed on airplanes 
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
----------------------------------------------------------------------------------------------------------------
Initial FPI...........................  2 work-hours x $85 per                $0            $170         $29,920
                                         hour = $170.
----------------------------------------------------------------------------------------------------------------

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 
associated 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, 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):

2018-03-13 General Electric Company: Amendment 39-19186; Docket No. 
FAA-2017-0943; Product Identifier 2017-NE-34-AD.

(a) Effective Date

    This AD is effective February 28, 2018.

(b) Affected ADs

    None.

[[Page 6127]]

(c) Applicability

    This AD applies to General Electric Company (GE) CT7-5A2, CT7-
5A3, CT7-7A, CT7-7A1, CT7-9B, CT7-9B1, CT7-9B2, CT7-9C and CT7-9C3 
model turboprop engines with main propeller shaft, part number 
77581-11, installed.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7210, Turbine Engine 
Reduction Gear.

(e) Unsafe Condition

    This AD was prompted by the failure of a main propeller shaft. 
We are issuing this AD to prevent failure of the main propeller 
shaft. The unsafe condition, if not addressed, could result in in-
flight loss of the propeller, loss of engine thrust control, and 
damage to the airplane.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Required Actions

    (1) For propeller gear boxes (PGBs) with 46,000 hours time since 
new (TSN) or more, perform cleaning, visual inspection, and 
fluorescent-penetrant inspection (FPI) within 150 hours time in 
service (TIS) after the effective date of this AD, or one month 
after the effective date of this AD, whichever occurs first.
    (2) For PGBs with 40,000 hours TSN or more, but less than 46,000 
hours TSN, perform cleaning, visual inspection, and FPI within 500 
hours TIS after the effective date of this AD, not to exceed 46,150 
TSN or four months after the effective date of this AD, whichever 
occurs first.
    (3) For PGBs with 30,000 hours TSN or more, but less than 40,000 
hours TSN, perform cleaning, visual inspection, and FPI within 1,000 
hours TIS after the effective date of this AD, not to exceed 40,500 
TSN or eight months after the effective date of this AD, whichever 
occurs first.
    (4) For PGBs with less than 30,000 hours TSN, perform cleaning, 
visual inspection, and FPI at the next propeller removal, not to 
exceed 31,000 hours TSN.
    (5) Perform the cleaning, visual inspection and FPI, as follows:
    (i) Clean the main propeller shaft flange. Use the instructions 
in paragraph 5, ``Main Propeller Shaft,'' in MM 72-10-00, PROPELLER 
GEARBOX--CLEANING from GE CT7B Maintenance Manual SEI-576, Rev. 60, 
dated October 1, 2017.
    (ii) Visually inspect the main propeller shaft for wear, 
corrosion, and cracking. Use the instructions in paragraph 5.A., 
``Main Propeller Shaft,'' in MM 72-10-00, PROPELLER GEARBOX--
INSPECTION from GE CT7B Maintenance Manual SEI-576, Rev. 60, dated 
October 1, 2017.
    (iii) Spot-fluorescent-penetrant inspect the area on the main 
propeller shaft flange face within 0.5 inches radially adjacent to 
the dowel pin holes for cracks. Use the instructions in SPM 70-32-
03, SPOT-FLUORESCENT PENETRANT--INSPECTION, Task 70-32-03-230-002 
from GE GEK 9250, Commercial Engine Standard Practices Manual, Rev. 
106, dated April 1, 2007.
    (6) Repeat the cleaning, visual inspection, and FPI of the main 
propeller shaft at each removal of the propeller.
    (7) Before further flight, remove from service any main 
propeller shaft found cracked, or with corrosion or wear beyond the 
limits specified in SPM 70-32-03, SPOT-FLUORESCENT PENETRANT--
INSPECTION, Task 70-32-03-230-002, from GE GEK 9250, Commercial 
Engine Standard Practices Manual, Rev. 106, dated April 1, 2007.

(h) Credit for Previous Actions

    Main propeller shafts that were replaced with new zero-time 
parts at an overhaul of the PGB within the last 10,000 hours TIS, or 
inspected in accordance with GE Service Bulletin (SB) CT7-TP S/B 72-
0531, dated June 22, 2017, or GE SB CT7-TP S/B 72-0533, dated 
October 3, 2017, satisfy the requirements specified in paragraph 
(g)(5) of this AD.

(i) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, ECO Branch, FAA, has the authority to approve 
AMOCs for this AD, if requested using the procedures found in 14 CFR 
39.19. In accordance with 14 CFR 39.19, send your request to your 
principal inspector or local Flight Standards District Office, as 
appropriate. If sending information directly to the manager of the 
ECO Branch, send it to the attention of the person identified in 
paragraph (j) of this AD. You may email your request to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(j) Related Information

    For more information about this AD, contact Michael Richardson-
Bach, Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: 781-238-7747; fax: 781-238-7199; email: 
[email protected].

(k) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) SPM 70-32-03, SPOT-FLUORESCENT PENETRANT INSPECTION, TASK 
70-32-03-230-002, from the GE Commercial Engine Standard Practices 
Manual GEK 9250, Rev. 106, dated April 01, 2007.
    (ii) MM 72-10-00, PROPELLER GEARBOX INSPECTION, from the GE CT7B 
Maintenance Manual SEI-576, Rev. 60, dated October 1, 2017.
    (iii) MM 72-10-00, PROPELLER GEARBOX--CLEANING, from the GE CT7B 
Maintenance Manual SEI-576, Rev. 60, dated October 1, 2017.
    (3) For GE 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: 
[email protected].
    (4) You may view this service information at FAA, Engine and 
Propeller Standards Branch, 1200 District Avenue, Burlington, MA 
01803. For information on the availability of this material at the 
FAA, call 781-238-7759.
    (5) You may view this service information that is incorporated 
by reference 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.

    Issued in Burlington, Massachusetts, on February 8, 2018.
Robert J. Ganley,
Acting Manager, Engine and Propeller Standards Branch, Aircraft 
Certification Service.
[FR Doc. 2018-02917 Filed 2-12-18; 8:45 am]
BILLING CODE 4910-13-P