Published 2019-02-15 · Federal Register document 2019-02453
Airworthiness Directives; Pratt & Whitney Division (PW) Turbofan Engines
Publication summary
We are adopting a new airworthiness directive (AD) for certain Pratt & Whitney Division (PW) PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 turbofan engines. This AD was prompted by an in-flight failure of a 1st-stage low-pressure compressor (LPC) blade. This AD requires initial and repetitive thermal acoustic imaging (TAI) inspections for cracks in certain 1st-stage LPC blades and removal of those blades that fail inspection. We are issuing this AD to address the unsafe condition on these products.
Why this record is shown
Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:24:01.312311+00:00. The title, summary and date are source facts.
- Source revision
- federal_register_ad_metadata_2019-66422190cf4fa9dc
- Source row
- results[16]
- Raw source SHA-256
- 66422190cf4fa9dc96bac02b1afe14648e349a1393bef6cf5fbf55644fa2ce43
Final-rule publication
Recorded publication clauses
- AD identifier printed in this edition
- 2019-03-01
- Effective date printed in this edition
- 2019-03-22
Read 11 complete recorded clauses
Effective Date
(a) Effective Date
This AD is effective March 22, 2019.
Exact source excerpt. Text positions 11904–11966, end exclusive, in the original decoded publication. SHA-256: 67cff97a63687f647eb9924bb09e5ea97ad86f787bc3596e351305a18e6efb29
Affected ADs
(b) Affected ADs
None.
Exact source excerpt. Text positions 11966–11995, end exclusive, in the original decoded publication. SHA-256: 871a4afc60ceeae06e8010585055188633d616078500c45937092bfe892239c0
Applicability wording · Applicability
(c) Applicability
This AD applies to all Pratt & Whitney Division (PW) PW4074,
PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 turbofan
engines, with 1st-stage low-pressure compressor (LPC) blade, part
numbers 52A241, 55A801, 55A801-001, 55A901, 55A901-001, 56A201,
56A201-001, or 56A221, installed.
Exact source excerpt. Text positions 11995–12313, end exclusive, in the original decoded publication. SHA-256: e58fff3d35ac6137694f33ff66d88629df7b3e4116a0e3a7015200d47885931a
Subject
(d) Subject
Joint Aircraft System Component (JASC) Code 7230, Turbine Engine
Compressor Section.
Exact source excerpt. Text positions 12313–12417, end exclusive, in the original decoded publication. SHA-256: 151db2778cdfea7f0edc36f3dc91c040e977d403cabb29f1bb70ebf8781db722
Unsafe Condition
(e) Unsafe Condition
This AD was prompted by an uncontained 1st-stage LPC blade
failure. We are issuing this AD to prevent failure of the 1st-stage
LPC blade. The unsafe condition, if not addressed, could result in
uncontained blade release, damage to the engine, and damage to the
airplane.
Exact source excerpt. Text positions 12417–12719, end exclusive, in the original decoded publication. SHA-256: 3a1ba3a04e4c8b6d203c92aa85374690440e5444934ea64d5b91052eefc28672
Compliance
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
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Required Actions
(g) Required Actions
(1) After the effective date of this AD, perform an initial
thermal acoustic imaging (TAI) inspection of the 1st-stage LPC
blades as follows:
(i) For 1st-stage LPC blades that have accumulated fewer than
6,500 cycles since new (CSN), perform a TAI inspection the next time
the engine is separated at the M-flange, or prior to the 1st-stage
LPC blade accumulating 7,000 CSN, whichever occurs first.
(ii) For 1st-stage LPC blades that have accumulated 6,500 or
more CSN, or if the cycles since the blade was new cannot be
determined, or if the cycles since the blade was last TAI inspected
cannot be determined, perform a TAI inspection within 500 flight
cycles or 180 days after the effective date of this AD, whichever
occurs first.
(2) Thereafter, perform a TAI inspection of 1st-stage LPC blades
every time the engine is separated at the M-flange and the blades
have accumulated 1,000 or more flight cycles since the last TAI
inspection, not to exceed 6,500 flight cycles since the last TAI
inspection.
(3) If any 1st-stage LPC blade fails the inspection required by
paragraph (g)(1) or (2) of this AD, remove the blade from service
and replace with a part eligible for installation before further
flight.
(4) The TAI inspection and disposition required for compliance
with this AD must be accomplished by a method approved by the FAA.
You can find a vendor that has an FAA-approved TAI inspection listed
in the Vendor Services Section of Pratt & Whitney Alert Service
Bulletin (ASB) PW4G-112-A72-268, Revision No. 7, dated September 6,
2018.
Exact source excerpt. Text positions 12821–14435, end exclusive, in the original decoded publication. SHA-256: a201cc36a29fa94ffe5ec5dd039aed8d0ee721fc939cb3dcea99460f6095b000
Credit for Previous Actions
(h) Credit for Previous Actions
You may take credit for the initial TAI inspection required by
paragraph (g)(1) of this AD if you performed the TAI inspection
before the effective date of this AD using Pratt & Whitney ASB PW4G-
112-A72-268, Revision No. 6, dated August 5, 2014, or earlier
revisions.
Exact source excerpt. Text positions 14435–14745, end exclusive, in the original decoded publication. SHA-256: db9481b165b292df58911d38a1aaa9057b948be573916eec14df0f003dbefdd7
Alternative Methods of Compliance (AMOCs)
(i) 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 paragraph (j) of this AD. You may email your request
to: [email protected].
(2) Before using any approved AMOC, notify your appropriate
principal inspector, or lacking a principal inspector, the manager
[[Page 4323]]
of the local flight standards district office/certificate holding
district office.
Exact source excerpt. Text positions 14745–15518, end exclusive, in the original decoded publication. SHA-256: 839bc28f5e0c8283249e91d0c51cd6fed57f30744b32bd3381e2d9bbea213c4a
Related Information
(j) Related Information
For more information about this AD, contact Jo-Ann Theriault,
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue,
Burlington, MA 01803; phone: 781-238-7105; fax: 781-238-7199; email:
[email protected].
Exact source excerpt. Text positions 15518–15760, end exclusive, in the original decoded publication. SHA-256: 486b1be1a93edffa4184962428d498997d06d6d7ca43d42dfa6428c2b53e77db
Material Incorporated by Reference
(k) 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.
(3) The following service information was approved for IBR on
March 22, 2019.
(i) Pratt & Whitney Alert Service Bulletin PW4G-112-A72-268,
Revision No. 7, dated September 6, 2018.
(ii) [Reserved].
(4) For Pratt & Whitney service information identified in this
AD, contact Pratt & Whitney Division, 400 Main Street, East
Hartford, CT, 06118; phone: 800-565-0140; fax: 860-565-5442; email:
[email protected].
(5) You may view this service information at the FAA, Engine and
Propeller Standards Branch, 1200 District Avenue, Burlington, MA
01803. For information on the availability of this material at the
FAA, call 781-238-7759.
(6) 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, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.
Exact source excerpt. Text positions 15760–17077, end exclusive, in the original decoded publication. SHA-256: f1ad2f7db9a3ac25a63512b20762cd8ed9068c51ed15f8d57550d1402b6ce769
No replacement link has been established from this edition. The complete historical rule chain and current legal effect remain unknown.
Find all recorded historical references to AD 2019-03-01 · 0 printed reference observations in this pinned collection.
These are observations from one dated publication. Current legal status is unknown; aircraft applicability, installed configuration, compliance and burden require separate evidence. Missing or unparsed conditions remain unknown.
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They were extracted offline from the same immutable official HTML source as the complete recorded text. The dated source wording, original text coordinates and exact quote digests are retained. PDF/text agreement and current regulatory effect have not been qualified.
Observation revision: whole-ad-publication-clause-observations-1.0.1. Text SHA-256: 2970229a5638dab66fc675f46d7812e0c6d8e640c00ee901f44eb08cee0d783f. Source manifest: 3b9742350544fcbe15d16979c4b9feae75705719264951b5fdffb77f6ec2b4cd.
Official source · 2019-02-15
Publication text
This is the complete recorded text of this dated publication.
Current legal effect is unknown. Aircraft applicability, installed configuration and compliance require separate evidence. PDF/text agreement has not been evaluated.
Read the complete official publication text
[Federal Register Volume 84, Number 32 (Friday, February 15, 2019)]
[Rules and Regulations]
[Pages 4320-4323]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-02453]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2018-0826; Product Identifier 2018-NE-27; Amendment 39-
19553; AD 2019-03-01]
RIN 2120-AA64
Airworthiness Directives; Pratt & Whitney Division (PW) Turbofan
Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: We are adopting a new airworthiness directive (AD) for certain
Pratt & Whitney Division (PW) PW4074, PW4074D, PW4077, PW4077D,
PW4084D, PW4090, and PW4090-3 turbofan engines. This AD was prompted by
an in-flight failure of a 1st-stage low-pressure compressor (LPC)
blade. This AD requires initial and repetitive thermal acoustic imaging
(TAI) inspections for cracks in certain 1st-stage LPC blades and
removal of those blades that fail inspection. We are issuing this AD to
address the unsafe condition on these products.
DATES: This AD is effective March 22, 2019.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of March 22,
2019.
ADDRESSES: For service information identified in this final rule,
contact Pratt & Whitney Division, 400 Main Street, East Hartford, CT,
06118; phone: 800-565-0140; fax: 860-565-5442; email:
[email protected]. You may view this
[[Page 4321]]
service information at the FAA, Engine and Propeller Standards 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 on the internet at http://www.regulations.gov by searching
for and locating Docket No. FAA-2018-0826.
Examining the AD Docket
You may examine the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2018-
0826; 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 regulatory evaluation, any comments received, and
other information. The address for Docket Operations (phone: 800-647-
5527) is U.S. Department of Transportation, Docket Operations, M-30,
West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE,
Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Jo-Ann Theriault, Aerospace Engineer,
ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone:
781-238-7105; fax: 781-238-7199; email: [email protected].
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 by adding an AD that would apply to certain PW PW4074, PW4074D,
PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 turbofan engines. The
NPRM published in the Federal Register on October 10, 2018 (83 FR
50862). The NPRM was prompted by an in-flight failure of a 1st-stage
LPC blade. The NPRM proposed to require initial and repetitive TAI
inspections for cracks in certain 1st-stage LPC blades and removal of
those blades that fail inspection. We are issuing this AD to address
the unsafe condition on these products.
Comments
We gave the public the opportunity to participate in developing
this final rule. The following presents the comments received on the
NPRM and the FAA's response to each comment.
Request To Give Credit for Earlier Revisions of PW ASB
PW and Japan Airlines (JAL) requested that we revise the Credit for
Previous Actions paragraph of this AD to give credit for revisions of
Pratt & Whitney Alert Service Bulletin (ASB) PW4G-112-A72-268, earlier
than Revision No. 6, dated August 5, 2014. PW and JAL reason that TAI
inspections performed using earlier revisions of the PW ASB meet the
requirements of this AD.
We agree. We revised the Credit for Previous Actions paragraph of
this AD to give credit for accomplishing the initial TAI inspection if
operators used Pratt & Whitney ASB PW4G-112-A72-268, Revision No. 6,
dated August 5, 2014, or earlier revisions, because this meets the
intended safety requirements of this AD.
Request To Clarify Installation Prohibition
PW and JAL requested that we revise the Installation Prohibition
paragraph to align with the wording in Table 1, Step 3, of Pratt &
Whitney ASB PW4G-112-A72-268, Revision No. 7, dated September 6, 2018,
which states, ``All blades that have never been TAI inspected but have
accumulated greater than 1,000 cycles must be inspected prior to
December 31, 2027.'' JAL reasoned that the intent of the Installation
Prohibition is the same as the PW ASB.
JAL also requested that we define ``install 1st-stage LPC blade''
and clarify that the Installation Prohibition paragraph does not
prohibit removing and reinstalling 1st-stage LPC blades for the purpose
of relubrication.
We partially agree. We agree that the intent of the Installation
Prohibition section in the NPRM was the same as the PW ASB. We also
agree that 1st-stage LPC blades that are removed solely for
relubrication do not need to be inspected before reinstallation because
this AD intends to inspect 1st-stage LPC blades at every M-flange
separation. We do not agree, however, to modify the Installation
Prohibition paragraph as we have determined that this paragraph is
unnecessary because the AD already requires the initial inspections at
specific thresholds. These thresholds provide an acceptable level of
safety. We removed the Installation Prohibition paragraph from this AD.
Support for the AD
The Air Line Pilots Association, Boeing Company, and the National
Transportation Safety Board expressed support for the NPRM as written.
Conclusion
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
this final rule with the changes described previously and minor
editorial changes. We have determined that these minor changes:
<bullet> Are consistent with the intent that was proposed in the
NPRM for addressing the unsafe condition; and
<bullet> Do not add any additional burden upon the public than was
already proposed in the NPRM.
We also determined that these changes will not increase the
economic burden on any operator or increase the scope of this final
rule.
Related Service Information Under 1 CFR Part 51
We reviewed Pratt & Whitney ASB PW4G-112-A72-268, Revision No. 7,
dated September 6, 2018. The PW ASB describes procedures for performing
1st-stage LPC blade TAI inspections. 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
the ADDRESSES section.
Costs of Compliance
We estimate that this AD affects 120 engines installed on airplanes
of U.S. registry.
We estimate the following costs to comply with this AD:
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Cost per Cost on U.S.
Action Labor cost Parts cost product operators
----------------------------------------------------------------------------------------------------------------
Inspection......................... 22 work-hours x $85 per $0 $1,870 $224,400
hour = $1,870.
----------------------------------------------------------------------------------------------------------------
We estimate the following costs to do any necessary replacements
that would be required based on the results of the proposed inspection.
We have no way of determining the number of aircraft that might need
these replacements:
[[Page 4322]]
On-Condition Costs
----------------------------------------------------------------------------------------------------------------
Cost per
Action Labor cost Parts cost product
----------------------------------------------------------------------------------------------------------------
Replace 1st-stage LPC blade................ 0 work-hours x $85 per hour = $0... $125,000 $125,000
----------------------------------------------------------------------------------------------------------------
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.
We are 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.
This AD is issued in accordance with authority delegated by the
Executive Director, Aircraft Certification Service, as authorized by
FAA Order 8000.51C. In accordance with that order, issuance of ADs is
normally a function of the Compliance and Airworthiness Division, but
during this transition period, the Executive Director has delegated the
authority to issue ADs applicable to engines, propellers, and
associated appliances to the Manager, Engine and Propeller Standards
Branch, Policy and Innovation Division.
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) Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979),
(3) Will not affect intrastate aviation in Alaska, and
(4) Will 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.
Adoption of 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):
2019-03-01 Pratt & Whitney Division: Amendment 39-19553; Docket No.
FAA-2018-0826; Product Identifier 2018-NE-27-AD.
(a) Effective Date
This AD is effective March 22, 2019.
(b) Affected ADs
None.
(c) Applicability
This AD applies to all Pratt & Whitney Division (PW) PW4074,
PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 turbofan
engines, with 1st-stage low-pressure compressor (LPC) blade, part
numbers 52A241, 55A801, 55A801-001, 55A901, 55A901-001, 56A201,
56A201-001, or 56A221, installed.
(d) Subject
Joint Aircraft System Component (JASC) Code 7230, Turbine Engine
Compressor Section.
(e) Unsafe Condition
This AD was prompted by an uncontained 1st-stage LPC blade
failure. We are issuing this AD to prevent failure of the 1st-stage
LPC blade. The unsafe condition, if not addressed, could result in
uncontained 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) After the effective date of this AD, perform an initial
thermal acoustic imaging (TAI) inspection of the 1st-stage LPC
blades as follows:
(i) For 1st-stage LPC blades that have accumulated fewer than
6,500 cycles since new (CSN), perform a TAI inspection the next time
the engine is separated at the M-flange, or prior to the 1st-stage
LPC blade accumulating 7,000 CSN, whichever occurs first.
(ii) For 1st-stage LPC blades that have accumulated 6,500 or
more CSN, or if the cycles since the blade was new cannot be
determined, or if the cycles since the blade was last TAI inspected
cannot be determined, perform a TAI inspection within 500 flight
cycles or 180 days after the effective date of this AD, whichever
occurs first.
(2) Thereafter, perform a TAI inspection of 1st-stage LPC blades
every time the engine is separated at the M-flange and the blades
have accumulated 1,000 or more flight cycles since the last TAI
inspection, not to exceed 6,500 flight cycles since the last TAI
inspection.
(3) If any 1st-stage LPC blade fails the inspection required by
paragraph (g)(1) or (2) of this AD, remove the blade from service
and replace with a part eligible for installation before further
flight.
(4) The TAI inspection and disposition required for compliance
with this AD must be accomplished by a method approved by the FAA.
You can find a vendor that has an FAA-approved TAI inspection listed
in the Vendor Services Section of Pratt & Whitney Alert Service
Bulletin (ASB) PW4G-112-A72-268, Revision No. 7, dated September 6,
2018.
(h) Credit for Previous Actions
You may take credit for the initial TAI inspection required by
paragraph (g)(1) of this AD if you performed the TAI inspection
before the effective date of this AD using Pratt & Whitney ASB PW4G-
112-A72-268, Revision No. 6, dated August 5, 2014, or earlier
revisions.
(i) 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 paragraph (j) of this AD. You may email your request
to: [email protected].
(2) Before using any approved AMOC, notify your appropriate
principal inspector, or lacking a principal inspector, the manager
[[Page 4323]]
of the local flight standards district office/certificate holding
district office.
(j) Related Information
For more information about this AD, contact Jo-Ann Theriault,
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue,
Burlington, MA 01803; phone: 781-238-7105; fax: 781-238-7199; email:
[email protected].
(k) 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.
(3) The following service information was approved for IBR on
March 22, 2019.
(i) Pratt & Whitney Alert Service Bulletin PW4G-112-A72-268,
Revision No. 7, dated September 6, 2018.
(ii) [Reserved].
(4) For Pratt & Whitney service information identified in this
AD, contact Pratt & Whitney Division, 400 Main Street, East
Hartford, CT, 06118; phone: 800-565-0140; fax: 860-565-5442; email:
[email protected].
(5) You may view this service information at the FAA, Engine and
Propeller Standards Branch, 1200 District Avenue, Burlington, MA
01803. For information on the availability of this material at the
FAA, call 781-238-7759.
(6) 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, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.
Issued in Burlington, Massachusetts, on February 7, 2019.
Robert J. Ganley,
Manager, Engine and Propeller Standards Branch, Aircraft Certification
Service.
[FR Doc. 2019-02453 Filed 2-14-19; 8:45 am]
BILLING CODE 4910-13-P
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