DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-1808; Project Identifier MCAI-2023-00906-E;
Amendment 39-22537; AD 2023-17-11]
RIN 2120-AA64

Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG
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 all
Rolls-Royce Deutschland Ltd & Co KG (RRD) Model BR700-715A1-30, BR700-
715B1-30, and BR700-715C1-30 engines. This AD was prompted by reports
of malformed scallop edge geometry and surface conditions at the front
flange scallops of affected low-pressure compressor (LPC) booster
rotors. This AD requires repetitive fluorescent penetrant inspections
(FPIs) of the front flange scallops of the LPC booster rotor for any cracks,
replacement or repair of the LPC booster rotor if necessary and, as an
optional terminating action to the repetitive FPIs, a visual inspection
for malformed scallop edge geometry and malformed surface conditions,
as specified in a European Union Aviation Safety Agency (EASA) AD,
which is incorporated by reference (IBR). The FAA is issuing this AD to
address the unsafe condition on these products.

DATES: This AD is effective September 20, 2023.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of September
20, 2023.
The FAA must receive comments on this AD by October 20, 2023.

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 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.
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2023-1808; 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, the mandatory continuing airworthiness
information (MCAI), any comments received, and other information. The
street address for Docket Operations is listed above.
Material Incorporated by Reference:
For EASA service information identified in this final
rule, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany;
phone: +49 221 8999 000; email: ADs@easa.europa.eu. You may find this
material on the EASA website at ad.easa.europa.eu.
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 (817) 222-5110. It is
also available at regulations.gov under Docket No. FAA-2023-1808.

FOR FURTHER INFORMATION CONTACT: Sungmo Cho, Aviation Safety Engineer,
FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: (781) 238-
7241; email: sungmo.d.cho@faa.gov.

SUPPLEMENTARY INFORMATION:

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
ADDRESSES. Include ``Docket No. FAA-2023-1808; Project Identifier MCAI-
2023-00906-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
regulations.gov, including any personal information you provide. The
agency will also post a report summarizing each substantive verbal
contact received about this final rule.

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 AD 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 AD, 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 AD. Submissions containing CBI should be sent to Sungmo
Cho, Aviation Safety Engineer, FAA, 2200 South 216th Street, Des
Moines, WA 98198. Any commentary that the FAA receives which is not
specifically designated as CBI will be placed in the public docket for
this rulemaking.

Background

EASA, which is the Technical Agent for the Member States of the
European Union, has issued EASA AD 2023-0152, dated July 25, 2023 (EASA
AD 2023-0152) (also referred to after this as the MCAI), to correct an
unsafe condition for all RRD Model BR700-715A1-30, BR700-715B1-30, and
BR700-715C1-30 engines. The MCAI states that occurrences have been
reported of finding malformed scallop edge geometry and surface
conditions at the front flange of scallops of certain LPC booster
rotors. To address this unsafe condition, the manufacturer published
service information that specifies procedures for inspecting the front
flange scallops of the LPC booster rotors with accept and reject
criteria.
Prior to the issuance of EASA AD 2023-0152, the FAA issued a notice
of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD
that would apply to RRD Model BR700-715A1-30, BR700-715B1-30, and
BR700-715C1-30 engines. The NPRM published in the Federal Register on
June 14, 2023 (88 FR 38762). The NPRM was prompted by EASA AD 2022-
0252, dated December 16, 2022 (later revised to EASA AD 2022-0252R1,
dated April 28, 2023 (EASA AD 2022-0252R1)). The NPRM proposed to
require repetitive FPIs of the front flange scallops of the LPC booster
rotor for any cracks, replacement or repair of the LPC booster rotor if
necessary and, as an optional terminating action to the repetitive
FPIs, a visual inspection for malformed scallop edge geometry and
malformed surface conditions to prevent failure of the LPC booster
rotor. However, since the NPRM was issued, the FAA has reviewed the
MCAI which supersedes EASA AD 2022-0252R1 and includes both reduced
compliance times for certain engines and extended compliance times for
certain other engines. Therefore, the FAA has determined that it is
necessary to withdraw the NPRM under a separate action; and instead
issue this final rule to address the unsafe condition.
For further information, you may examine the MCAI in the AD docket
at regulations.gov under Docket No. FAA-2023-1808.

Discussion of Notice of Proposed Rule Making

Comments

The FAA received comments from four commenters. Commenters included
Hawaiian Airlines (Hawaiian), Delta Air Lines (Delta), The Boeing
Company, and Air Line Pilots Association, International (ALPA). Boeing
and ALPA supported the NPRM without change. However, comments from
Hawaiian and Delta identified concerns with the NPRM. The FAA has
determined that it is necessary to withdraw the NPRM and instead issue
this final rule to address the unsafe condition. The following presents
the comments received on the NPRM and the FAA's response to each comment.

Requests To Revise the NPRM

Delta suggested that the instructions for the FPI referenced in
EASA AD 2022-0252 do not provide procedures for the application of non-
aqueous aerosol developer (NAD). Additionally, Delta requested that the
FAA include an exception to the AD to allow this NAD or industry
equivalent for the FPI procedure.
Delta pointed out that the manufacturer has published a revision to
the service information that was referenced in EASA AD 2022-0252 and
requested that the FAA include credit in the NPRM for actions
accomplished using RRD Non-Modification Service Bulletin (NMSB) SB-
BR700-72-A900738, Initial Issue, dated December 15, 2022. Delta
mentioned that the inspections specified in RRD NMSB SB-BR700-72-
A900738, Initial Issue, dated December 15, 2022, are equivalent to
those contained in RRD NMSB SB-BR700-72-A900738, Revision 1, dated July
11, 2023. The FAA infers that Delta is requesting that RRD NMSB SB-
BR700-72-A900738, Revision 1, dated July 11, 2023, as the required
service information for the actions specified in the NPRM.
Hawaiian stated that the materials necessary to accomplish the
required actions listed in the NPRM are obsolete or otherwise
unavailable for use in the United States. Hawaiian requested that the
FAA revise the NPRM to include suitable materials for accomplishing the
required actions.
After careful consideration of these comments, the FAA agrees to
withdraw the NPRM. However, the FAA will accomplish the withdrawal of
the NPRM as a separate action. The MCAI specified in this final rule
refers to the revised service information, and both now adequately
address the concerns Delta and Hawaiian. The FAA has updated this final
rule to include the revised service information which also contains the
change of materials necessary to support the required inspections.

Conclusion

These products have been approved by the aviation authority of
another country and are approved for operation in the United States.
Pursuant to the FAA's bilateral agreement with this State of Design
Authority, it has notified the FAA of the unsafe condition described in
the MCAI referenced above. The FAA reviewed the relevant data,
considered the comments received, and has determined to withdraw the
NPRM. Instead of publishing the NPRM, the FAA has also determined that
air safety requires adopting this final rule. Accordingly, the FAA is
issuing this AD to address the unsafe condition on these products.

Related Service Information Under 1 CFR Part 51

The FAA reviewed EASA AD 2023-0152, which specifies procedures for
accomplishing repetitive FPIs (on-wing or in-shop) of the front flange
scallops of the affected part and, if any cracks are detected, removing
the engine from service and contacting the manufacturer for approved
corrective actions. EASA AD 2023-0152 also specifies procedures for
performing a visual inspection, taking photographs, and submitting
photograph documentation of the LPC booster rotor front flange scallops
for malformed scallop edge geometry and malformed surface conditions,
including validation of the results from the manufacturer, as
terminating action for the repetitive FPIs.
This material is reasonably available because the interested
parties have access to it through their normal course of business or by
the means identified in ADDRESSES.

FAA's Determination

These products have been approved by the aviation authority of
another country and are approved for operation in the United States.
Pursuant to the FAA's bilateral agreement with this State of Design
Authority, it has notified the FAA of the unsafe condition described in
the MCAI referenced above. The FAA is issuing this AD after determining
that the unsafe condition described previously is likely to exist or
develop on other products of the same type design.

AD Requirements

This AD requires accomplishing the actions specified in the MCAI,
except for any differences identified as exceptions in the regulatory
text of this AD, and except as discussed under ``Differences Between
this AD and the MCAI.'' This AD requires sending certain inspection
results, the Part C Accomplishment Form, and photographic evidence to
the manufacturer if operators elect to perform the optional terminating
action specified in Part C of the service information referenced in
EASA AD 2023-0152.

Differences Between This AD and the MCAI

Where paragraphs (2) and (3) of EASA AD 2023-0152 specify to
contact RRD for approved corrective action(s) and accomplish those
actions accordingly, this AD requires replacement or repair of the LPC
booster rotor.
Where paragraph (1) requires accomplishment of the initial
inspection to be determined by certain flight missions and engine
flight cycles (EFC), after the effective date of the EASA AD, but not
later than August 31, 2023, this AD requires accomplishment of the
initial inspection within 150 EFC after the effective date of this AD.

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. 551 et seq.) 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 thirty 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 forgoing notice and comment prior to adoption of this rule
due to a reassessment performed by the manufacturer that determined an
increased risk of a crack developing on the LPC booster. This unsafe
condition may result in release of high-energy debris, with consequent
engine in-flight shutdown, and reduced control of the airplane. Due to
this increased risk, the FPI of the LPC booster for cracking must be
accomplished within 150 flight cycles (which is equivalent to 30 days)
after the effective date of this AD. Accordingly, notice and
opportunity for prior public comment are impracticable and contrary to
the 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.

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 prior notice and comment,
RFA analysis is not required.

Costs of Compliance

The FAA estimates that this AD affects 148 engines installed on
airplanes of U.S. registry.
The FAA estimates the following costs to comply with this AD:

Estimated Costs

The FAA estimates the following costs to do any necessary
replacement, repair, or visual inspection that would be required based
on the results of the inspection. The agency has no way of determining
the number of engines that might need this replacement, repair, or
visual inspection:

On-Condition Costs

Paperwork Reduction Act

A federal agency may not conduct or sponsor, and a person is not
required to respond to, nor shall a person be subject to a penalty for
failure to comply with a collection of information subject to the
requirements of the Paperwork Reduction Act unless that collection of
information displays a currently valid OMB Control Number. The OMB
Control Number for this information collection is 2120-0056. Public
reporting for this collection of information is estimated to take
approximately 1 hour per response, including the time for reviewing
instructions, searching existing data sources, gathering and
maintaining the data needed, and completing and reviewing the
collection of information. All responses to this collection of
information are mandatory. Send comments regarding this burden estimate
or any other aspect of this collection of information, including
suggestions for reducing this burden, to: Information Collection
Clearance Officer, Federal Aviation Administration, 10101 Hillwood
Parkway, Fort Worth, TX 76177-1524.

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, and
(2) Will not affect intrastate aviation in Alaska.

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

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]

2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive: