Document ID: FAA-2021-1071-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Rolls-Royce Corporation Turboshaft Engines
Posted Date: 2022-01-14T05:00Z

[Federal Register Volume 87, Number 10 (Friday, January 14, 2022)]
[Proposed Rules]
[Pages 2365-2367]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-00232]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-1071; Project Identifier AD-2021-01055-E]
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: The FAA proposes to supersede Airworthiness Directive (AD) 
2017-18-14, which applies to certain Rolls-Royce Corporation (RRC) 250 
model turboshaft engines. AD 2017-18-14 requires repetitive visual 
inspections and fluorescent penetrant inspections (FPIs) of the 3rd-
stage turbine wheel and removal from service of the 4th-stage turbine 
wheel. Since the FAA issued AD 2017-18-14, the manufacturer redesigned 
the 3rd-stage turbine wheel. This proposed AD would require replacement 
of the 3rd-stage and 4th-stage turbine wheels. This proposed AD would 
also revise the applicability to add an additional turboshaft engine 
model. The FAA is proposing this AD to address the unsafe condition on 
these products.

DATES: The FAA must receive comments on this proposed AD by February 
28, 2022.

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 https://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.
    For service information identified in this NPRM, contact Rolls-
Royce Corporation, 450 South Meridian Street, Mail Code NB-01-06, 
Indianapolis, IN 46225; phone: (317) 230-2720; email: 
Royce.com">[email protected]Royce.com; website: www.rolls-royce.com. You may 
view this service information at the Airworthiness Products Section, 
Operational Safety Branch, FAA, 1200 District Avenue, Burlington, MA 
01803. For information on the availability of this material at the FAA, 
call (817) 222-5110.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-1071; or in person at 
Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The AD docket contains this NPRM, any comments 
received, and other information. The street address for Docket 
Operations is listed above.

FOR FURTHER INFORMATION CONTACT: John Tallarovic, Aviation Safety 
Engineer, Chicago ACO, FAA, 2300 E Devon Avenue, Des Plaines, IL 60018; 
phone:

[[Page 2366]]

(847) 294-8180; fax: (847) 294-7834; email: [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2021-1071; Project Identifier 
AD-2021-01055-E'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
the proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
https://www.regulations.gov, including any personal information you 
provide. The agency will also post a report summarizing each 
substantive verbal contact we receive about this proposed AD.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this NPRM contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this NPRM, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this NPRM. Submissions containing CBI should be sent to John 
Tallarovic, Aviation Safety Engineer, Chicago ACO, FAA, 2300 E. Devon 
Avenue, Des Plaines, IL 60018. Any commentary that the FAA receives 
which is not specifically designated as CBI will be placed in the 
public docket for this rulemaking.

Background

    The FAA issued AD 2017-18-14, Amendment 39-19023 (82 FR 42443, 
September 8, 2017), (AD 2017-18-14), for 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 a 4th-stage turbine wheel, P/N 23055944 or 
RR30000240, installed. AD 2017-18-14 was prompted by in-service turbine 
blade failures that revealed the need for changes to the inspections of 
a certain 3rd-stage turbine wheel and removal from service of a certain 
4th-stage turbine wheel. AD 2017-18-14 requires repetitive visual 
inspections and FPIs of the 3rd-stage turbine wheel and removal from 
service of the 4th-stage turbine wheel. AD 2017-18-14 also revises the 
applicability to remove all RRC turboprop engines and adds additional 
turboshaft engines. The agency issued AD 2017-18-14 to prevent failure 
of the 3rd-stage and 4th-stage turbine wheel blades, damage to the 
engine, and damage to the aircraft.

Actions Since AD 2017-18-14 Was Issued

    Since the FAA issued AD 2017-18-14, the manufacturer redesigned the 
3rd-stage turbine wheel. The manufacturer has issued Rolls-Royce (RR) 
Alert Commercial Engine Bulletin (CEB) CEB A-1428/CEB A-72-4111 (single 
document), specifying procedures for replacement of the 3rd-stage 
turbine wheel, P/N 23065818, with the new increased blade fillet 3rd-
stage turbine wheel, P/N M250-10473. Additionally, the FAA determined 
that the RRC 250-C20C (T63-A-720) model turboshaft engine is also 
susceptible to the unsafe condition. The FAA, therefore, added RRC 250-
C20C (T63-A-720) model turboshaft engines to the applicability of this 
proposed AD. The FAA is proposing this AD to require the replacement of 
3rd-stage and 4th-stage turbine wheels with redesigned 3rd-stage and 
4th-stage turbine wheels.

FAA's Determination

    The FAA is issuing this NPRM after determining that the unsafe 
condition described previously is likely to exist or develop on other 
products of the same type design.

Related Service Information

    The FAA reviewed RR Alert CEB CEB A-1428/CEB A-72-4111 (single 
document), Revision 1, dated September 29, 2021. This service 
information describes procedures for replacing the 3rd-stage turbine 
wheel, P/N 23065818, with the new increased blade fillet 3rd-stage 
turbine wheel, P/N M250-10473.
    The FAA reviewed Rolls-Royce Alert CEB CEB-A-1422/CEB-A-72-4108 
(single document), Original Issue, dated September 13, 2017. This 
service information describes procedures for replacing 4th-stage 
turbine wheel, P/N 23055944, with the new increased fillet 4th-stage 
turbine wheel, P/N M250-10445.
    The FAA also reviewed Rolls-Royce Alert Service Bulletin SB RR300-
A-72-024, Original Issue, dated September 13, 2017. This service 
information describes procedures for replacing the 4th-stage turbine 
wheel, P/N RR30000240, with the new increased fillet 4th-stage turbine 
wheel, P/N RR30000494.

Proposed AD Requirements in This NPRM

    This proposed AD would require removal and replacement of the 3rd-
stage and 4th-stage turbine wheels.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 3,041 3rd-stage stage turbine wheels and 3,769 4th-stage stage 
turbine wheels installed on helicopters of U.S. registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                      Cost per
            Action                  Labor cost       Parts cost        product         Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
Replace 3rd-stage turbine       3 work-hours x            $11,170         $11,425  $34,743,425 (3,041 engines).
 wheel, P/N 23065818.            $85 per hour =
                                 $255.
Replace 4th-stage turbine       3 work-hours x              8,928           9,183  $34,610,727 (3,769 engines).
 wheel, P/N 23055944 or          $85 per hour =
 RR30000240.                     $255.
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[[Page 2367]]

    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some of the costs of this 
proposed AD may be covered under warranty, thereby reducing the cost 
impact on affected individuals.

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.
    The FAA is 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

    The FAA 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) Would not affect intrastate aviation in Alaska, 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.

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:
0
a. Removing Airworthiness Directive 2017-18-14, Amendment 39-19023 (82 
FR 42443, September 8, 2017); and
0
b. Adding the following new airworthiness directive:

Rolls-Royce Corporation: Docket No. FAA-2021-1071; Project 
Identifier AD-2021-01055-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) action by February 28, 2022.

(b) Affected ADs

    This AD replaces AD 2017-18-14, Amendment 39-19023 (82 FR 42443, 
September 8, 2017).

(c) Applicability

    This AD applies to Rolls-Royce Corporation (RRC) 250-C20, 250-
C20B, 250-C20C (T63-A-720), 250-C20F, 250-C20J, 250-C20R, 250-C20R/
1, 250-C20R/2, 250-C20R/4, 250-C20W, 250-C300/A1, and 250-C300/B1 
model turboshaft engines with either a 3rd-stage turbine wheel, part 
number (P/N) 23065818, or a 4th-stage turbine wheel, P/N 23055944 or 
RR30000240, installed.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by in-service turbine blade failures that 
resulted in the loss of power and engine in-flight shutdowns. The 
FAA is issuing this AD to prevent failure of the 3rd-stage and 4th-
stage turbine blades. The unsafe condition, if not addressed, could 
result in damage to the engine and damage to the aircraft.

(f) Compliance

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

(g) Required Actions

    (1) Within 1,775 hours since last visual inspection and 
fluorescent penetrant inspection (FPI), or at the next engine shop 
visit, whichever occurs first after the effective date of this AD, 
remove:
    (i) 3rd-stage turbine wheel, P/N 23065818, and replace with a 
part eligible for installation.
    (ii) 4th-stage turbine wheel, P/N 23055944, and replace with a 
part eligible for installation.
    (2) Within 2,025 hours since last visual inspection and FPI 
inspection, or at the next engine shop visit, whichever occurs first 
after the effective date of this AD, remove 4th-stage turbine wheel, 
P/N RR30000240, and replace with a part eligible for installation.

(h) Definitions

    (1) For this purpose of this AD, an ``engine shop visit'' is the 
induction of an engine into the shop for maintenance in which the 
turbine module is separated from the exhaust collector, the gas-
producer-support is separated from the power-turbine-support, or 
there is 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.
    (2) For the purpose of this AD, a ``part eligible for 
installation'' is a 3rd-stage turbine wheel or 4th-stage turbine 
wheel that does not have a P/N listed in the Applicability, 
paragraph (c), of this AD.

(i) Special Flight Permit

    A special flight permit may be issued in accordance with 14 CFR 
21.197 and 21.199 to permit a one-time, non-revenue ferry flight to 
operate the airplane to a maintenance facility where the engine can 
be removed from service. This ferry flight must be performed with 
only essential flight crew.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Chicago ACO, 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 
certification office, send it to the attention of the person 
identified in paragraph (k) of this AD.
    (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.

(k) Related Information

    For more information about this AD, contact John Tallarovic, 
Aviation Safety Engineer, Chicago ACO, FAA, 2300 E Devon Avenue, Des 
Plaines, IL 60018; phone: (847) 294-8180; fax: (847) 294-7834; 
email: [email protected].

    Issued on December 9, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2022-00232 Filed 1-13-22; 8:45 am]
BILLING CODE 4910-13-P