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

[Federal Register Volume 85, Number 147 (Thursday, July 30, 2020)]
[Rules and Regulations]
[Pages 45769-45773]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-16680]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0679; Project Identifier AD-2020-01060-E; 
Amendment 39-21197; AD 2020-16-13]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain

[[Page 45770]]

Rolls-Royce Corporation (RRC) AE 3007A, AE 3007A1, AE 3007A1/1, AE 
3007A1/2, AE 3007A1/3, AE 3007A1E, AE 3007A1P, and AE 3007A3 model 
turbofan engines. This 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 AD requires 
replacement of affected 3rd-stage compressor wheels. The FAA is issuing 
this AD to address the unsafe condition on these products.

DATES: This AD is effective August 14, 2020.
    The FAA must receive comments on this AD by September 14, 2020.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
    <bullet> Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments.
    <bullet> Fax: 202-493-2251.
    <bullet> 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.
    <bullet> 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 
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; internet: 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 on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-
0679; 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 final rule, any comments received, and other information. The 
street address for the Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Kyri Zaroyiannis, Aerospace Engineer, 
Chicago ACO, FAA, 2300 E Devon Ave., Des Plaines, IL 60018; phone: 
(847) 294-7836; fax: (847) 294-7834; email: [email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA learned of an uncommanded IFSD of a RRC AE 3007A1 model 
turbofan engine installed on an Embraer S.A. ERJ-145 airplane 
conducting a revenue flight. The manufacturer's investigation of this 
incident revealed that the IFSD resulted 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 
and parts from this manufacturing lot require removal from service. 
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. The FAA is issuing this AD to address the unsafe 
condition on these products.

FAA's Determination

    The FAA is issuing this AD because the agency 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.

Related Service Information

    The FAA reviewed Rolls-Royce Alert Service Bulletin (ASB) AE 3007A-
A-72-446, Revision 2, dated July 28, 2020. The ASB describes procedures 
for replacing certain 3rd-stage compressor wheels.

AD Requirements

    This AD requires replacement of certain 3rd-stage compressor wheels 
before they accumulate a specified number of cycles.

FAA's Justification for Immediate Adoption and Determination of the 
Effective Date

    Section 553(b)(3)(B) of the Administrative Procedure Act (APA) (5 
U.S.C.) authorizes agencies to dispense with notice and comment 
procedures for rules when the agency, for ``good cause,'' finds that 
those procedures are ``impracticable, unnecessary, or contrary to the 
public interest.'' Under this section, an agency, upon finding good 
cause, may issue a final rule without providing notice and seeking 
comment prior to issuance. Further, section 553(d) of the APA 
authorizes agencies to make rules effective in less than 30 days, upon 
a finding of good cause.
    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. 
RRC inspected a RRC AE3007A1 model turbofan engine after it experiences 
an uncommanded IFSD during a revenue flight on an Embraer ERJ-145 
airplane.
    The manufacturer's inspection discovered a low-cycle fatigue crack 
in a 3rd-stage compressor wheel that allowed a 3rd-stage compressor 
blade to release during the flight. The manufacturer traced the cause 
of the cracked 3rd-stage compressor wheel to a specific machining 
process that occurred during manufacture of the 3rd-stage compressor 
wheels. The manufacturer's subsequent investigation discovered multiple 
3rd-stage compressor wheels in the affected serial numbered population 
with similar low-cycle fatigue cracks. The 3rd-stage compressor wheels 
identified in this AD are unable to remain in service beyond the cycles 
since new limits listed in paragragh (g) of this AD. As a result of the 
shortened compliance times established based on the FAA's risk 
assessment, the FAA has determined that there is insufficient time 
available to allow for notice and opportunity for prior public comment.
    The FAA considers the removal of these 3rd-stage compressor wheels 
from service to be an urgent safety issue. Exceeding the reduced cycle 
limits on the 3rd-stage compressor wheels required by this AD could 
lead to failure of the 3rd-stage compressor wheel and high-energy 
release of the 3rd-stage compressor wheel, resulting in damage to the 
engine and damage to the airplane. Accordingly, notice and opportunity 
for prior public comment are impracticable and contrary to public 
interest pursuant to 5 U.S.C. 553(b)(3)(B).
    In addition, the FAA finds that good cause exists pursuant to 5 
U.S.C. 553(d) for making this amendment effective in less than 30 days, 
for the same reasons the FAA found good cause to forgo notice and 
comment.

[[Page 45771]]

Comments Invited

    The FAA invites 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 FAA-2020-0679 and 
Project Identifier AD-2020-01060-E at the beginning of your comments. 
The most helpful comments reference a specific portion of the final 
rule, 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 final rule 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 FAA will also post a report summarizing each substantive 
verbal contact received about this final rule.

Confidential Business Information

    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 final rule 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 final rule, 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 final rule. Submissions 
containing CBI should be sent to Kyri Zaroyiannis, Aerospace Engineer, 
Chicago ACO, FAA, 2300 E. Devon Ave., 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.

Regulatory Flexibility Act

    The requirements of the Regulatory Flexibility Act (RFA) do not 
apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt 
a rule without prior notice and comment. Because the FAA has determined 
that it has good cause to adopt this rule without notice and comment, 
RFA analysis is not required.

Costs of Compliance

    The FAA estimate that this AD affects 4 engines installed on 
airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Remove 3rd-stage compressor wheel.....  40 work-hours x $85 per               $0          $3,400         $13,600
                                         hour = $3,400.
Replace 3rd-stage compressor wheel....  85 work-hours x $85 per           32,844          40,069         160,276
                                         hour = $7,225.
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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

    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) Will not affect intrastate aviation in Alaska, and

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

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):

2020-16-13 Rolls-Royce Corporation (Type Certificate previously held 
by Allison Engine Company): Amendment 39-21197; Docket No. FAA-2020-
0679; Project Identifier AD-2020-01060-E.

(a) Effective Date

    This AD is effective August 14, 2020.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Rolls-Royce Corporation (RRC) AE 3007A, AE 
3007A1, AE 3007A1/1, AE 3007A1/2, AE 3007A1/3, AE 3007A1E, AE 
3007A1P, and AE 3007A3 model turbofan 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.
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(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

    (1) For AE 3007A, AE 3007A1, AE 3007A1/1, AE 3007A1/2, AE 
3007A1/3, AE 3007A1P, and AE 3007A3 model turbofan engines, prior to 
the 3rd-stage compressor wheel accumulating the cycles listed in 
Table 1 to paragraph (g)(1) of this AD or before further flight, 
whichever occurs later after the effective date of this AD, remove 
the affected 3rd-stage compressor wheel and replace with a part 
eligible for installation.
[GRAPHIC] [TIFF OMITTED] TR30JY20.024

    (2) For AE 3007A1E model turbofan engines, prior to the 3rd-
stage compressor wheel accumulating the cycles listed in Table 2 to 
paragraph (g)(2) of this AD or before further flight, whichever 
occurs later after the effective date of this AD, remove the 
affected 3rd-stage compressor wheel and replace with a part eligible 
for installation.

[[Page 45773]]

[GRAPHIC] [TIFF OMITTED] TR30JY20.025

(h) Definitions

    (1) 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.
    (2) 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, except that the 
separation of engine flanges solely for the purposes of 
transportation of the engine without subsequent engine maintenance 
does not constitute an engine shop visit.

(i) Special Flight Permit

    (1) Special flight permits, as described in Section 21.197 and 
Section 21.199 of the Federal Aviation Regulations (14 CFR 21.197 
and 21.199), are subject to the requirements of paragraph (i)(1)(i) 
of this AD.
    (i) Operators may perform 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.
    (ii) [Reserved]
    (2) [Reserved]

(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, 
Aerospace Engineer, Chicago ACO, FAA, 2300 E Devon Ave., Des 
Plaines, IL 60018; phone: (847) 294-7836; fax: (847) 294-7834; 
email: [email protected].

(l) Material Incorporated by Reference

    None.

    Issued on July 28, 2020.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2020-16680 Filed 7-28-20; 4:15 pm]
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