[Federal Register Volume 86, Number 194 (Tuesday, October 12, 2021)]
[Proposed Rules]
[Pages 56660-56662]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-22091]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0874; Project Identifier AD-2021-00668-E]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce Corporation (Type 
Certificate Previously Held by Allison Engine Company) Turboprop 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain Rolls-Royce Corporation (RRC) AE 2100D3 model turboprop 
engines. This proposed AD was prompted by an in-flight shutdown (IFSD) 
of an engine and subsequent investigation by the manufacturer that 
revealed a crack in the 3rd-stage compressor wheel. This proposed AD 
would require replacement of the affected 3rd-stage compressor wheel. 
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 November 
26, 2021.

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) 230-1667; email: 
royce.com">CMSEindyOSD@rolls-royce.com; website: www.rolls-royce.com. You may view 
this service information at the FAA, Airworthiness Products Section, 
Operational Safety Branch, 1200 District Avenue, Burlington, MA 01803. 
For information on the availability of this material at the FAA, call 
(781) 238-7759.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0874; 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: Kyri Zaroyiannis, Aviation Safety 
Engineer, Chicago ACO, FAA, 2300 E Devon Avenue, Des Plaines, IL 60018; 
phone: (847) 294-7836; 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-2021-0874; Project Identifier 
AD-2021-00668-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 
this 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 received about this NPRM.

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 Kyri 
Zaroyiannis, 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 was notified of an uncommanded IFSD of a RRC AE 3007A1 
model turbofan engine installed on an Embraer S.A. model EMB-145 
airplane (marketed as ERJ-145), while conducting a revenue flight. The 
manufacturer's investigation of this incident revealed that the IFSD 
resulted

[[Page 56661]]

from a low-cycle fatigue crack in the dovetail slot for the blade 
attachment in the 3rd-stage compressor wheel, causing one 3rd-stage 
compressor blade to release. The crack initiated in the dovetail slot 
due to a sharp corner in the wheel slot geometry. The broaching process 
was identified as the cause of the crack and parts from this 
manufacturing lot required removal from service.
    In response to this event and the manufacturer's subsequent 
investigation, the FAA issued a final rule; request for comments, AD 
2020-16-13 (85 FR 45769, July 30, 2020), requiring replacement of 
certain 3rd-stage compressor wheels installed on RRC AE 3007A, AE 
3007A1, AE 3007A1/1, AE 3007A1/2, AE 3007A1/3, AE 3007A1E, AE 3007A1P, 
and AE 3007A3 model turbofan engines before the 3rd-stage compressor 
wheels accumulate a specified number of cycles. The actions required by 
AD 2020-16-13 address engines that experienced high stresses at the 3rd 
stage compressor wheel location and accumulated cycles at a high rate. 
The FAA now proposes to require removal of certain AE 2100D3 3rd-stage 
compressor wheels that were produced in the same lot as the AE 3007 
3rd-stage compressor wheels identified in AE 2020-16-13, before they 
accumulate a specified number of cycles. This condition, if not 
addressed, could result in uncontained release of the 3rd-stage 
compressor wheel, damage to the engine, and damage to the airplane.

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 Rolls-Royce Alert Service Bulletin (ASB) AE 
2100D3-A-72-330, Engine--3rd Stage Compressor Wheel Removal for Reduced 
Life Limit, dated June 11, 2021. The ASB specifies procedures for 
removal of a certain 3rd-stage compressor wheel.

Proposed AD Requirements in This NPRM

    This proposed AD would require replacement of a certain 3rd-stage 
compressor wheel before it accumulates a specified number of cycles.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 15 engines installed on airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Remove and replace 3rd-stage            125 work-hours x $85 per         $32,844         $43,469        $652,035
 compressor wheel.                       hour = $10,625.
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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.
    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 this 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 adding the following new airworthiness 
directive:

Rolls-Royce Corporation (Type Certificate previously held by Allison 
Engine Company): Docket No. FAA-2021-0874; Project Identifier AD-
2021-00668-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by November 26, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Rolls-Royce Corporation (RRC) AE 2100D3 model 
turboprop engines with a 3rd-stage compressor wheel, part number (P/
N) 23084158, and with a serial number listed in Figure 1 to 
paragraph (c) of this AD.

[[Page 56662]]

[GRAPHIC] [TIFF OMITTED] TP12OC21.000

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by an in-flight shutdown of an engine 
during a revenue flight and subsequent investigation by the 
manufacturer that revealed a crack in the 3rd-stage compressor 
wheel. The FAA is issuing this AD to prevent failure of the 3rd-
stage compressor wheel. The unsafe condition, if not addressed, 
could result in an uncontained release of the 3rd-stage compressor 
wheel, damage to the engine, and damage to the airplane.

(f) Compliance

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

(g) Required Actions

    Before the affected 3rd-stage compressor wheel exceeds 5,200 
flight cycles since new, remove the affected 3rd-stage compressor 
wheel and replace with a part eligible for installation.

(h) Definition

    For the purpose of this AD, a part eligible for installation is 
a 3rd-stage compressor wheel that does not have a P/N and a serial 
number 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 
a location 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 Kyri Zaroyiannis, 
Aviation Safety Engineer, Chicago ACO, FAA, 2300 E Devon Avenue, Des 
Plaines, IL 60018; phone: (847) 294-7836; fax: (847) 294-7834; 
email: [email protected].

    Issued on October 5, 2021.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-22091 Filed 10-8-21; 8:45 am]
BILLING CODE 4910-13-P