```

[Federal Register Volume 86, Number 111 (Friday, June 11, 2021)]
[Rules and Regulations]
[Pages 31092-31095]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-12302]

-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0445; Project Identifier AD-2021-00268-E; 
Amendment 39-21588; AD 2021-12-01]
RIN 2120-AA64

Airworthiness Directives; Engine Alliance Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

-----------------------------------------------------------------------

SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2019-25-
13, which applied to all Engine Alliance (EA) GP7270 and GP7277 model 
turbofan engines with a certain low-pressure compressor (LPC) 1st-stage 
fan blade installed. AD 2019-25-13 required an ultrasonic inspection of 
the affected LPC 1st-stage fan blades and replacement of any affected 
LPC 1st-stage fan blade that fails the inspection. This AD lowers the 
initial inspection threshold and requires repetitive ultrasonic 
inspections on affected LPC 1st-stage fan blades. This AD was prompted 
by a report of an in-flight shutdown (IFSD) of an engine due to the 
fracture of multiple LPC 1st-stage fan blades. The FAA is issuing this 
AD to address the unsafe condition on these products.

DATES: This AD is effective June 28, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of June 28, 
2021.
    The FAA must receive any comments on this AD by July 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 final rule, contact 
Engine Alliance, 411 Silver Lane, East Hartford, CT 06118; phone: (800) 
565-0140; email: [email protected]; website: 
www.engineallianceportal.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. It is 
also available at https://www.regulations.gov by searching for and 
locating Docket No. FAA-2021-0445.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0445; 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 Docket 
Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Stephen Elwin, Aviation Safety 
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; 
phone: (781) 238-7236; fax: (781) 238-7199; email: 
[email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA issued AD 2019-25-13, Amendment 39-21011 (84 FR 71770, 
December 30, 2019), (AD 2019-25-13), for all EA GP7270 and GP7277 model 
turbofan engines with a certain LPC 1st-stage fan blade installed. AD 
2019-25-13 required an ultrasonic inspection of the affected LPC 1st-
stage fan blades and replacement of any affected fan blades that fail 
the inspection. AD 2019-25-13 resulted from a report of an IFSD of an 
engine due to the fracture of multiple LPC 1st-stage fan blades. After 
an analysis of these fractures, the

[[Page 31093]]

manufacturer determined the fan blades experienced cracks that 
originated on the internal surface of the convex airfoil and propagated 
to the point of failure. The cracks originated in a microtexture area 
that can result in a low-cycle fatigue debit that may allow a crack to 
initiate and propagate to failure. The FAA issued AD 2019-25-13 to 
prevent failure of the fan blade.

Actions Since AD 2019-25-13 Was Issued

    Since the FAA issued AD 2019-25-13, the manufacturer performed 
analysis of a fractured LPC 1st-stage fan blade and determined the 
fracture resulted from a fatigue crack. The manufacturer determined 
that repetitive ultrasonic inspection for cracks on the LPC 1st-stage 
fan blade convex airfoil is necessary to decrease the risk of fracture 
event. As a result of this analysis, the manufacturer published EA 
Alert Service Bulletin (SB) EAGP7-A72-444, dated November 18, 2020. 
This service information specifies lower initial inspection thresholds 
for performing ultrasonic inspections of affected LPC 1st-stage fan 
blades and contains procedures for performing repetitive ultrasonic 
inspections of affected LPC 1st-stage fan blades. 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 determined the unsafe 
condition described previously is likely to exist or develop in other 
products of the same type design.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed EA Alert SB EAGP7-A72-444, dated November 18, 
2020. The Alert SB describes the inspection thresholds and procedures 
for performing an ultrasonic inspection of the LPC 1st-stage fan 
blades. This service information is reasonably available because the 
interested parties have access to it through their normal course of 
business or by the means identified in ADDRESSES.

AD Requirements

    This AD requires initial and repetitive ultrasonic inspections of 
the affected LPC 1st-stage fan blades and replacement of any LPC 1st-
stage fan blade that fails the inspection.

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.
    The FAA has found the risk to the flying public justifies waiving 
notice and comment prior to adoption of this rule because no domestic 
operators use this product. It is unlikely that the FAA will receive 
any adverse comments or useful information about this AD from any U.S. 
operator. Accordingly, notice and opportunity for prior public comment 
are unnecessary, pursuant to 5 U.S.C. 553(b)(3)(B). In addition, for 
the foregoing reason, 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.

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-2021-0445 and Project Identifier 
AD-2021-00268-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 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 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 Stephen 
Elwin, Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803. 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 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 0 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
----------------------------------------------------------------------------------------------------------------
Perform ultrasonic inspection for one   8 work-hours x $85 per                $0            $680              $0
 set of 1st--stage LPC blades.           hour = $680.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary 
replacements that would be required based on the results of the 
inspection. The agency has no way of determining the number of

[[Page 31094]]

aircraft that might need these replacements.

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replace 1st-stage LPC fan blade...............  4 work-hours x $85 per hour =           $190,000        $190,340
                                                 $340.
----------------------------------------------------------------------------------------------------------------

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

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 2019-25-13, Amendment 39-21011 (84 
FR 71770, December 30, 2019); and
0
b. Adding the following new airworthiness directive:

2021-12-01 Engine Alliance: Amendment 39-21588; Docket No. FAA-2021-
0445; Project Identifier AD-2021-00268-E.

(a) Effective Date

    This airworthiness directive (AD) is effective June 28, 2021.

(b) Affected ADs

    This AD replaces AD 2019-25-13, Amendment 39-21011 (84 FR 71770, 
December 30, 2019).

(c) Applicability

    This AD applies to Engine Alliance (EA) GP7270 and GP7277 model 
turbofan engines with low-pressure compressor (LPC) 1st-stage fan 
blades, part number (P/N) 5700531, 5702931, 5702931CL1, or 
5702931CL2, installed.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by a report of an in-flight shutdown of an 
engine due to the fracture of multiple LPC 1st-stage fan blades. The 
FAA is issuing this AD to prevent failure of the LPC 1st-stage fan 
blades. The unsafe condition, if not addressed, could result in 
uncontained fan blade release, 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) Within the compliance time specified in Table 1 to paragraph 
(g)(1) of this AD, perform an ultrasonic inspection of the LPC 1st-
stage fan blades using the Accomplishment Instructions, ``For Fan 
Blades Installed In An Engine,'' paragraph 1, or ``For Fan Blades 
Not Installed In An Engine,'' paragraph 1, as applicable, of EA 
Alert Service Bulletin (SB) EAGP7-A72-444, dated November 18, 2020.
[GRAPHIC] [TIFF OMITTED] TR11JN21.000

[[Page 31095]]

    (2) Thereafter, at intervals not to exceed 800 flight cycles 
since last inspection, perform an ultrasonic inspection of the LPC 
1st-stage fan blades using the Accomplishment Instructions, ``For 
Fan Blades Installed In An Engine,'' paragraph 1, or ``For Fan 
Blades Not Installed In An Engine,'' paragraph 1, as applicable, of 
EA Alert SB EAGP7-A72-444, dated November 18, 2020.
    (3) If an ultrasonic inspection of an LPC 1st-stage fan blade 
results in a rejectable ultrasonic indication, remove the LPC 1st-
stage fan blade from service and replace with a part eligible for 
installation before further flight.

    Note 1 to paragraph (g)(3): Guidance on determining a rejectable 
ultrasonic indication can be found in GP7000 1st Stage LPC Rotor 
(Fan) Blade Assembly Airfoil Ultrasonic Inspection for Cracks (Fan 
Blade Installed or Uninstalled), NDIP-1205, Revision C, dated 
September 15, 2020.

(h) Credit for Previous Actions

    You may take credit for the ultrasonic inspection required by 
paragraph (g)(1) of this AD if you performed the inspection before 
the effective date of this AD using GP7000 1st Stage LPC Rotor (Fan) 
Blade Assembly Airfoil Ultrasonic Inspection for Cracks (Fan Blade 
installed or uninstalled), NDIP-1205, Revision B, dated September 
27, 2019, or an earlier version.

(i) No Reporting Requirement

    The reporting requirements contained within NDIP-1205 are not 
required by this AD.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, ECO Branch, 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 Related Information. Information may be emailed to: 
[email protected].
    (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 Stephen Elwin, 
Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: (781) 238-7236; fax: (781) 238-7199; 
email: [email protected].

(l) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Engine Alliance (EA) Alert Service Bulletin EAGP7-A72-444, 
dated November 18, 2020.
    (ii) [Reserved]
    (3) For EA service information identified in this AD, contact 
Engine Alliance, 411 Silver Lane, East Hartford, CT 06118; phone: 
(800) 565-0140; email: [email protected]; website: 
www.engineallianceportal.com.
    (4) You may view this service information at 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.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, email: [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on May 25, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-12302 Filed 6-10-21; 8:45 am]
BILLING CODE 4910-13-P
```