[Federal Register Volume 82, Number 59 (Wednesday, March 29, 2017)]
[Proposed Rules]
[Pages 15474-15476]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-06174]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0961; Directorate Identifier 2011-NE-22-AD]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce Corporation Turboshaft 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to supersede Airworthiness Directive (AD) 2015-02-
22, which applies to certain Rolls-Royce Corporation (RRC) model 250 
turboprop and turboshaft engines. AD 2015-02-22 currently requires 
repetitive visual inspections and fluorescent-penetrant inspection 
(FPIs) on certain 3rd-stage and 4th-stage turbine wheels for cracks in 
the turbine wheel blades. Since we issued AD 2015-02-22, we determined 
that it is necessary to remove the 4th-stage wheels at the next 
inspection. We are also proposing to revise the applicability to remove 
all RRC turboprop engines and add additional turboshaft engines. This 
proposed AD would require repetitive visual inspections and FPIs of 
3rd-stage turbine wheels while removing from service 4th-stage turbine 
wheels. We are proposing this AD to correct the unsafe condition on 
these products.

DATES: We must receive comments on this proposed AD by May 15, 2017.

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: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

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-2011-
0961; 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: John Tallarovic, Aerospace Engineer, 
Chicago Aircraft Certification Office, FAA, 2300 E. Devon Ave., Des 
Plaines, IL 60018; phone: 847-294-8180; fax: 847-294-7834; email: 
[email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this NPRM. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2011-0961; 
Directorate Identifier 2011-NE-22-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this NPRM. We will 
consider all comments received by the closing date and may amend this 
NPRM 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 NPRM.

Discussion

    On January 20, 2015, we issued AD 2015-02-22, Amendment 39-18090 
(80 FR 5452, February 2, 2015), (``AD 2015-02-22''), for certain RRC 
250-B17, -B17B, -B17C, -B17D, -B17E, -B17F, -B17F/1, -B17F/2, turboprop 
engines; and 250-C20, -C20B, -C20F, -C20J, -C20R, -C20R/1, -C20R/2, -
C20R/4, -C20S, and -C20W turboshaft engines. Note that, for the 
purposes of this proposed AD, we now consider the RRC 250-C20S engine a 
turboprop engine. RRC engine type certificate data sheet No. E4CE, 
Revision 42, dated June 29, 2010, classifies it as a turboshaft engine, 
but then clarifies in Note 11 that it functions as a turboprop engine.
    AD 2015-02-22 requires repetitive visual inspections and FPIs on 
certain

[[Page 15475]]

3rd-stage and 4th-stage turbine wheels. AD 2015-02-22 resulted from the 
determination that the one-time inspections required by AD 2012-14-06 
(77 FR 40479, July 10, 2012) should be changed to repetitive 
inspections. We issued AD 2015-02-22 to prevent failure of 3rd-stage 
and 4th-stage turbine wheel blades, damage to the engine, and damage to 
the aircraft.

Actions Since AD 2015-02-22 Was Issued

    Since we issued AD 2015-02-22, we determined that it is necessary 
to remove the 4th-stage wheels at the next inspection, before the 
scheduled life limit for these wheels. We also determined that the RRC 
turboprop engines are not susceptible to the unsafe condition and 
therefore do not require inspection or removal. We are, therefore, not 
including RRC turboprop engines in the applicability of this proposed 
AD. Additionally, we determined two additional part number turbine 
wheels are susceptible to the unsafe condition and are being included 
in this proposed AD.

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 in other products of the same type design.

Proposed AD Requirements

    This proposed AD would retain certain requirements of AD 2015-02-
22. This proposed AD would revise the requirement for the initial 
inspection from 1,750 hours since last inspection (HSLI) to 1,775 hours 
since last visual inspection and FPI or before the next flight after 
the effective date of this AD, whichever occurs later. Based on 
discussions with the manufacturer, we found that 1,775 hours since last 
visual inspection and FPI is an appropriate interval. We are also 
requiring inspections for additional part number wheels: (P/N) 
RR30000236 for the 3rd-stage turbine wheel and P/N RR30000240 for the 
4th-stage turbine wheel.
    This proposed AD would continue to require repetitive inspections 
of 3rd-stage turbine wheels. This proposed AD would also require 
removing from service 4th-stage turbine wheels at a reduced life limit. 
In addition, this proposed AD would add RRC 250-C300/A1 and 250-C300/B1 
turboshaft engines in the applicability.

Costs of Compliance

    We estimate that this proposed AD affects 3,769 engines installed 
on airplanes of U.S. registry.
    We estimate the following costs to comply with this proposed AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
              Action                      Labor cost             Parts cost           product        operators
----------------------------------------------------------------------------------------------------------------
Inspect 3rd-stage wheels, part      1 work-hour x $85 per  $0...................             $85        $320,365
 number (P/N) 23065818 or            hour = $85.
 RR30000236.
Replace 4th-stage wheel, P/N        0 work-hours x $85     $5,653 (pro-rated              $5,653     $21,306,157
 23055944 or RR30000240.             per hour = $0.         cost of part).
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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 
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 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.

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

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 removing Airworthiness Directive (AD) 
2015-02-22, Amendment 39-18090 (80 FR 5452, February 2, 2015), and 
adding the following new AD:

Rolls-Royce Corporation: Docket No. FAA-2011-0961; Directorate 
Identifier 2011-NE-22-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by May 15, 2017.

(b) Affected ADs

    This AD replaces Airworthiness Directive (AD) 2015-02-22, 
Amendment 39-18090 (80 FR 5452, February 2, 2015).

(c) Applicability

    This AD applies to Rolls-Royce Corporation (RRC) 250-C20, -C20B, 
-C20F, -C20J, -C20R, -C20R/1, -C20R/2, -C20R/4, -C20W, -C300/A1, and 
-C300/B1 turboshaft engines with either a 3rd-stage turbine wheel, 
part number (P/N) 23065818 or RR30000236, or a 4th-stage turbine 
wheel, P/N 23055944 or RR30000240, installed.

[[Page 15476]]

(d) Subject

    Joint Aircraft System Component (JASC) Code 7250, Turbine 
Section.

(e) Unsafe Condition

    This AD was prompted by in-service turbine wheel blade failures 
that revealed the need for changes to the inspections of certain 
3rd-stage turbine wheels and removal from service of certain 4th-
stage turbine wheels. We are issuing this AD to prevent failure of 
the 3rd-stage and 4th-stage turbine wheel blades, damage to the 
engine, and damage to the aircraft.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.
    (1) Within 1,775 hours since last visual inspection and 
fluorescent-penetrant inspection (FPI) or before the next flight 
after the effective date of this AD, whichever occurs later:
    (i) Remove 3rd-stage turbine wheels, P/N 23065818, and perform a 
visual inspection and an FPI on the removed turbine wheels for 
cracks at the trailing edge of the turbine blades, near the fillet 
at the rim.
    (ii) Thereafter, re-inspect the affected turbine wheels every 
1,775 hours since last inspection (HSLI).
    (2) Within 2,025 hours after the effective date of this AD:
    (i) Remove 3rd-stage turbine wheels, P/N RR30000236, and perform 
a visual inspection and an FPI on the removed turbine wheels for 
cracks at the trailing edge of the turbine blades, near the fillet 
at the rim.
    (ii) Thereafter, re-inspect the turbine wheels every 2,025 HSLI.
    (3) Any time the power turbine is disassembled, perform a visual 
inspection and an FPI on 3rd-stage turbine wheels, P/N 23065818 or 
P/N RR30000236, for cracks at the trailing edge of the turbine 
blades, near the fillet at the rim.
    (4) Do not return to service any turbine wheels found to have 
cracks.
    (5) Within 1,775 HSLI, or at the next engine shop visit, 
whichever occurs later, remove 4th-stage turbine wheels, P/N 
23055944, from service.
    (6) Within 2,025 HSLI, or at the next engine shop visit, 
whichever occurs later, remove 4th-stage turbine wheels, P/N 
RR30000240, from service.

(g) Definition

    For the purpose of this AD, ``engine shop visit'' is the 
induction of an engine into the shop for maintenance involving the 
separation of pairs of major mating engine flanges, except that the 
separation of engine flanges solely for the purposes of 
transportation without subsequent engine maintenance does not 
constitute an engine shop visit.

(h) Alternative Methods of Compliance (AMOCs)

    The Manager, Chicago Aircraft Certification Office, FAA, may 
approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 
to make your request.

(i) Related Information

    For more information about this AD, contact John Tallarovic, 
Aerospace Engineer, Chicago Aircraft Certification Office, FAA, 2300 
E. Devon Ave., Des Plaines, IL 60018; phone: 847-294-8180; fax: 847-
294-7834; email: [email protected].

    Issued in Burlington, Massachusetts, on March 17, 2017.
Thomas A. Boudreau,
Acting Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2017-06174 Filed 3-28-17; 8:45 am]
 BILLING CODE 4910-13-P