Airworthiness Directives; Pratt & Whitney Turbofan Engines, 29707-29709 [2021-11565]

Download as PDF Federal Register / Vol. 86, No. 105 / Thursday, June 3, 2021 / Proposed Rules AS355F1, AS355F2, AS355N, and AS355NP helicopters, certificated in any category, with litter kits installed having any part number specified in paragraphs (c)(1) through (3) of this AD: (1) Part number (P/N) 350–200034 (lefthand litter kit). (2) P/N 350–200194 (left-hand litter kit). (3) P/N 350–200144 (right-hand litter kit). (d) Subject Joint Aircraft Service Component (JASC) Code: 6700, Rotorcraft Flight Control. (e) Unsafe Condition This AD was prompted by reports that the lanyards (bead chain tethers), which hold the quick release pins to the forward bracket assembly of certain litter kits, can loop around the directional control pedal stubs, limiting the movement of the pedals, which affect the control of the flight. The FAA is issuing this AD to address interference between the litter kit lanyards and the flight controls. The unsafe condition, if not addressed, could result in limited flight control movement and difficulty controlling the helicopter. khammond on DSKJM1Z7X2PROD with PROPOSALS (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions (1) For litter kits having any part specified in paragraphs (c)(1) through (3) of this AD: Prior to each flight until the modification required by paragraph (g)(2) of this AD is accomplished, do a pre-flight check to determine if there is interference (e.g., limited movement of the pedals due to the lanyards that hold the quick release pins to the forward bracket assembly being looped around the directional control pedal stubs) between the lanyards that hold the quick release pins to the forward bracket assembly and the pedals. If interference is found, before further flight, do the modification required by paragraph (g)(2) of this AD for the affected litter kit. The pre-flight check may be performed by the owner/operator (pilot) holding at least a private pilot certificate and must be entered into the aircraft records showing compliance with this AD in accordance with § 43.9(a)(1) through (4) and § 91.417(a)(2)(v). The record must be maintained as required by § 91.417, § 121.380, or § 135.439. (2) Within 25 hours time-in-service (TIS) after the effective date of this AD, modify the attachment location of the lanyard for litter kits having any part specified in paragraphs (c)(1) through (3) of this AD. Do the modification in accordance with paragraph 3.B.2., ‘‘Procedure,’’ of the Accomplishment Instructions of Airbus Helicopters Service Bulletin SB–AHCA–128, Revision 0, dated March 24, 2017. Note 1 to paragraph (g): Litter kits, P/N 350–200034 and P/N 350–200194, may have been installed under STC SR00406NY (for Model AS355E, AS355F, AS355F1, AS355F2, AS355N, and AS355NP helicopters) or STC SR00407NY (for Model AS350B, AS350BA, AS350B1, AS350B2, AS350B3, and AS350D VerDate Sep<11>2014 16:29 Jun 02, 2021 Jkt 253001 helicopters). Litter kit P/N 350–200144 may have been installed under STC SR00458NY (for Model AS350BA, AS350B2, and AS350B3 helicopters). As of the effective date of this AD, no person may install a litter kit having a part number identified in paragraphs (c)(1) through (3) of this AD, on any helicopter, unless the installation is modified as required by paragraph (g)(2) of this AD. (i) Alternative Methods of Compliance (AMOCs) (1) The Manager, International Validation 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 International Validation Branch, send it to the attention of the person identified in paragraph (j)(1) of this AD. Information may be emailed to: 9-AVS-AIR730-AMOC@faa.gov. (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. (j) Related Information (1) For more information about this AD, contact Andrea Jimenez, Aerospace Engineer, COS Program Management Section, Operational Safety Branch, Compliance & Airworthiness Division, FAA, 1600 Stewart Ave., Mail Stop: Room 410, Westbury, NY 11590; telephone (516) 228–7330; email andrea.jimenez@faa.gov. (2) For information about AMOCs, contact the Manager, International Validation Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 222–5110; email 9-AVS-AIR-730-AMOC@faa.gov. (3) For service information identified in this AD, contact Airbus Helicopters, 2701 North Forum Drive, Grand Prairie, TX 75052; telephone (972) 641–0000 or (800) 232–0323; fax (972) 641–3775; or at https:// www.airbus.com/helicopters/services/ technical-support.html. You may view this referenced service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N– 321, Fort Worth, TX 76177. For information on the availability of this material at the FAA, call (817) 222–5110. (4) The subject of this AD is addressed in Transport Canada AD CF–2017–37 dated December 19, 2017. You may view the Transport Canada AD on the internet at https://www.regulations.gov in Docket No. FAA–2021–0449. Issued on May 27, 2021. Lance T. Gant, Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2021–11615 Filed 6–2–21; 8:45 am] PO 00000 Frm 00004 Fmt 4702 Sfmt 4702 DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 (h) Parts Installation Limitation BILLING CODE 4910–13–P 29707 [Docket No. FAA–2021–0447; Project Identifier AD–2021–00131–E] RIN 2120–AA64 Airworthiness Directives; Pratt & Whitney Turbofan Engines Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: The FAA proposes to adopt a new airworthiness directive (AD) for all Pratt & Whitney (PW) PW1500G and PW1900G series turbofan engines. This proposed AD was prompted by reports of cracks in the high-pressure compressor (HPC) rotor shaft that resulted in in-flight shutdowns (IFSDs) and unscheduled engine removals (UERs). This proposed AD would require removal and replacement of the HPC front hub and HPC rotor shaft. 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 July 19, 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 Pratt & Whitney, 400 Main Street, East Hartford, CT 06118; phone: (800) 565–0140; fax: (860) 565–5442; email: help24@pw.utc.com; website: https://fleetcare.pw.utc.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. SUMMARY: Examining the AD Docket You may examine the AD docket at https://www.regulations.gov by searching for and locating Docket No. E:\FR\FM\03JNP1.SGM 03JNP1 29708 Federal Register / Vol. 86, No. 105 / Thursday, June 3, 2021 / Proposed Rules FAA–2021–0447; 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: Mark Taylor, Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: (781) 238–7229; fax: (781) 238–7199; email: Mark.Taylor@faa.gov. 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–2021–0447; Project Identifier AD– 2021–00131–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 Mark Taylor, 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. develop on other products of the same type design. Background The FAA received reports of cracks in the HPC rotor shaft that resulted in vibration and subsequent IFSDs and UERs. The manufacturer determined that the threads on the HPC rotor shaft were not optimized for load distribution, which resulted in vibration stresses. During one occurrence, oil was released at the high-pressure turbine (HPT) disk bore location. The manufacturer redesigned the HPC front hub and HPC rotor shaft for increased durability and decreased vibration stress. The redesigned HPC front hub is made from nickel to help with corrosion resistance. The threads on the HPC rotor shaft were also redesigned to help distribute the load on the threads and decrease vibration stress. This condition, if not addressed, could result in release of an HPT disk, damage to the engine, and damage to the airplane. Differences Between This Proposed AD and the Service Information FAA’s Determination The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or Related Service Information The FAA reviewed Pratt & Whitney Service Bulletin (SB) PW1000G–A–72– 00–0154–00A–930A–D, Issue No. 001, dated May 7, 2021 (PW1000G–A–72– 00–0154–00A–930A–D), and Pratt & Whitney SB PW1000G–A–72–00–0101– 00B–930A–D, Issue No. 001, dated May 7, 2021 (SB PW1000G–A–72–00–0101– 00B–930A–D). These SBs describe procedures for removing and replacing the HPC front hub and HPC rotor shaft. Proposed AD Requirements in This NPRM This proposed AD would require removal and replacement of the HPC front hub and HPC rotor shaft. Pratt & Whitney SB PW1000G–A–72– 00–0154–00A–930A–D and Pratt & Whitney SB PW1000G–A–72–00–0101– 00B–930A–D provide instructions to concurrently perform the actions in Pratt & Whitney SB PW1000G–A–72– 00–0157–00A–930A–D and SB PW1000G–A–72–00–0105–00B–930A– D, respectively. This AD does not require performance of the actions described in Pratt & Whitney SB PW1000G–A–72–00–0157–00A–930A– D or SB PW1000G–A–72–00–0105–00B– 930A–D since these SBs describe ring seal replacement, which is not related to the unsafe condition addressed by this AD. Costs of Compliance The FAA estimates that this AD, if adopted as proposed, would affect 94 engines installed on airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD: khammond on DSKJM1Z7X2PROD with PROPOSALS ESTIMATED COSTS Action Labor cost Replace HPC front hub and HPC rotor shaft. 25.75 work-hours × $85 per hour = $2,188.75. 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. VerDate Sep<11>2014 16:29 Jun 02, 2021 Jkt 253001 Parts cost 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 PO 00000 Frm 00005 Fmt 4702 Sfmt 4702 $120,090 Cost per product Cost on U.S. operators $122,278.75 $11,494,202.50 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. E:\FR\FM\03JNP1.SGM 03JNP1 Federal Register / Vol. 86, No. 105 / Thursday, June 3, 2021 / Proposed Rules 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 1. The authority citation for part 39 continues to read as follows: ■ Authority: 49 U.S.C. 106(g), 40113, 44701. § 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new airworthiness directive: ■ Pratt & Whitney: Docket No. FAA–2021– 0447; Project Identifier AD–2021–00131– E. (a) Comments Due Date The FAA must receive comments on this airworthiness directive (AD) by July 19, 2021. khammond on DSKJM1Z7X2PROD with PROPOSALS (b) Affected ADs None. (c) Applicability This AD applies to Pratt & Whitney PW1519G, PW1521G, PW1521G–3, PW1521GA, PW1524G, PW1524G–3, PW1525G, PW1525G–3, PW1919G, PW1921G, PW1922G, PW1923G, and PW1923G–A model turbofan engines. (d) Subject Joint Aircraft System Component (JASC) Code 7230, Turbine Engine Compressor Section. 16:29 Jun 02, 2021 Jkt 253001 Issued on May 27, 2021. Gaetano A. Sciortino, Deputy Director for Strategic Initiatives, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2021–11565 Filed 6–2–21; 8:45 am] BILLING CODE 4910–13–P (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Action At next engine shop visit after the effective date of this AD, remove HPC front hub, part number (P/N) 30G1910 or 30G3210, and HPC rotor shaft, P/N 30G1854, 30G3109, 30G4995, 30G4953, or 31G0014, from service and replace each part with a part eligible for installation. DEPARTMENT OF THE INTERIOR Office of Surface Mining Reclamation and Enforcement 30 CFR Part 917 [SATS No. KY–263–FOR; Docket ID: OSM– 2020–0002; S1D1S SS08011000 SX064A000 212S180110; S2D2S SS08011000 SX064A000 21XS501520] (h) Definitions Kentucky Regulatory Program (1) 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 case flanges, except for the following, which do not constitute an engine shop visit: (i) Separation of engine flanges solely for the purposes of transportation without subsequent maintenance does not constitute an engine shop visit. (ii) Separation of engine flanges solely for the purpose of replacing the fan without subsequent maintenance does not constitute an engine shop visit. (2) For the purpose of this AD, a ‘‘part eligible for installation’’ is: (i) For a HPC front hub: Any HPC front hub with a P/N other than P/N 30G1910 or 30G3210; and (ii) For a HPC rotor shaft: Any HPC rotor shaft with a P/N other than P/N 30G1854, 30G3109, 30G4995, 30G4953, or 31G0014. AGENCY: (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 Related Information. You may email your request to: ANE-AD-AMOC@ faa.gov. (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. (j) Related Information (e) Unsafe Condition This AD was prompted by reports of cracks in the high-pressure compressor (HPC) rotor VerDate Sep<11>2014 shaft that resulted in in-flight shutdowns and unscheduled engine removals. The FAA is issuing this AD to prevent cracking of the HPC rotor shaft. The unsafe condition, if not addressed, could result in release of a highpressure turbine disk, damage to the engine, and damage to the airplane. 29709 For more information about this AD, contact Mark Taylor, Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: (781) 238–7229; fax: (781) 238–7199; email: Mark.Taylor@faa.gov. PO 00000 Frm 00006 Fmt 4702 Sfmt 4702 Office of Surface Mining Reclamation and Enforcement, Interior. ACTION: Proposed rule; public comment period and opportunity for public hearing on proposed amendment. We, the Office of Surface Mining Reclamation and Enforcement (OSMRE), are announcing receipt of a proposed amendment to the Kentucky regulatory program (hereinafter, the Kentucky program), under the Surface Mining Control and Reclamation Act of 1977 (SMCRA or the Act). Kentucky proposes to revise their administrative regulations to correct citations and revise language related to the repeal of the interim program regulations. This document gives the times and locations that the Kentucky program and this proposed amendment to that program are available for your inspection, the comment period during which you may submit written comments on the amendment, and the procedures that we will follow for the public hearing, if one is requested. DATES: We will accept written comments on this amendment until 4:00 p.m., Eastern Daylight Time (e.d.t.), July 6, 2021. If requested, we may hold a public hearing or meeting on the amendment on June 28, 2021. We will accept requests to speak at a hearing until 4:00 p.m., e.d.t. on June 18, 2021. ADDRESSES: You may submit comments, identified by SATS No. KY–263–FOR, by any of the following methods: • Mail/Hand Delivery: Mr. Michael Castle, Field Office Director, Lexington Field Office, Office of Surface Mining Reclamation and Enforcement, 2675 Regency Road, Lexington, KY 40503. • Fax: (859) 260–8410. • Federal eRulemaking Portal: The amendment has been assigned Docket ID OSM–2020–0002 If you would like to SUMMARY: E:\FR\FM\03JNP1.SGM 03JNP1

Agencies

[Federal Register Volume 86, Number 105 (Thursday, June 3, 2021)]
[Proposed Rules]
[Pages 29707-29709]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-11565]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0447; Project Identifier AD-2021-00131-E]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all Pratt & Whitney (PW) PW1500G and PW1900G series turbofan 
engines. This proposed AD was prompted by reports of cracks in the 
high-pressure compressor (HPC) rotor shaft that resulted in in-flight 
shutdowns (IFSDs) and unscheduled engine removals (UERs). This proposed 
AD would require removal and replacement of the HPC front hub and HPC 
rotor shaft. 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 July 19, 
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 Pratt & 
Whitney, 400 Main Street, East Hartford, CT 06118; phone: (800) 565-
0140; fax: (860) 565-5442; email: [email protected]; website: https://fleetcare.pw.utc.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.

[[Page 29708]]

FAA-2021-0447; 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: Mark Taylor, Aviation Safety Engineer, 
ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 
(781) 238-7229; fax: (781) 238-7199; 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-2021-0447; Project Identifier 
AD-2021-00131-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 Mark 
Taylor, 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.

Background

    The FAA received reports of cracks in the HPC rotor shaft that 
resulted in vibration and subsequent IFSDs and UERs. The manufacturer 
determined that the threads on the HPC rotor shaft were not optimized 
for load distribution, which resulted in vibration stresses. During one 
occurrence, oil was released at the high-pressure turbine (HPT) disk 
bore location. The manufacturer redesigned the HPC front hub and HPC 
rotor shaft for increased durability and decreased vibration stress. 
The redesigned HPC front hub is made from nickel to help with corrosion 
resistance. The threads on the HPC rotor shaft were also redesigned to 
help distribute the load on the threads and decrease vibration stress. 
This condition, if not addressed, could result in release of an HPT 
disk, 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 Pratt & Whitney Service Bulletin (SB) PW1000G-A-
72-00-0154-00A-930A-D, Issue No. 001, dated May 7, 2021 (PW1000G-A-72-
00-0154-00A-930A-D), and Pratt & Whitney SB PW1000G-A-72-00-0101-00B-
930A-D, Issue No. 001, dated May 7, 2021 (SB PW1000G-A-72-00-0101-00B-
930A-D). These SBs describe procedures for removing and replacing the 
HPC front hub and HPC rotor shaft.

Proposed AD Requirements in This NPRM

    This proposed AD would require removal and replacement of the HPC 
front hub and HPC rotor shaft.

Differences Between This Proposed AD and the Service Information

    Pratt & Whitney SB PW1000G-A-72-00-0154-00A-930A-D and Pratt & 
Whitney SB PW1000G-A-72-00-0101-00B-930A-D provide instructions to 
concurrently perform the actions in Pratt & Whitney SB PW1000G-A-72-00-
0157-00A-930A-D and SB PW1000G-A-72-00-0105-00B-930A-D, respectively. 
This AD does not require performance of the actions described in Pratt 
& Whitney SB PW1000G-A-72-00-0157-00A-930A-D or SB PW1000G-A-72-00-
0105-00B-930A-D since these SBs describe ring seal replacement, which 
is not related to the unsafe condition addressed by this AD.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 94 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
----------------------------------------------------------------------------------------------------------------
Replace HPC front hub and HPC rotor   25.75 work-hours x $85         $120,090     $122,278.75     $11,494,202.50
 shaft.                                per hour = $2,188.75.
----------------------------------------------------------------------------------------------------------------

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.

[[Page 29709]]

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:

Pratt & Whitney: Docket No. FAA-2021-0447; Project Identifier AD-
2021-00131-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by July 19, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Pratt & Whitney PW1519G, PW1521G, PW1521G-3, 
PW1521GA, PW1524G, PW1524G-3, PW1525G, PW1525G-3, PW1919G, PW1921G, 
PW1922G, PW1923G, and PW1923G-A model turbofan engines.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by reports of cracks in the high-pressure 
compressor (HPC) rotor shaft that resulted in in-flight shutdowns 
and unscheduled engine removals. The FAA is issuing this AD to 
prevent cracking of the HPC rotor shaft. The unsafe condition, if 
not addressed, could result in release of a high-pressure turbine 
disk, 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 Action

    At next engine shop visit after the effective date of this AD, 
remove HPC front hub, part number (P/N) 30G1910 or 30G3210, and HPC 
rotor shaft, P/N 30G1854, 30G3109, 30G4995, 30G4953, or 31G0014, 
from service and replace each part with a part eligible for 
installation.

(h) Definitions

    (1) 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 case flanges, except for 
the following, which do not constitute an engine shop visit:
    (i) Separation of engine flanges solely for the purposes of 
transportation without subsequent maintenance does not constitute an 
engine shop visit.
    (ii) Separation of engine flanges solely for the purpose of 
replacing the fan without subsequent maintenance does not constitute 
an engine shop visit.
    (2) For the purpose of this AD, a ``part eligible for 
installation'' is:
    (i) For a HPC front hub: Any HPC front hub with a P/N other than 
P/N 30G1910 or 30G3210; and
    (ii) For a HPC rotor shaft: Any HPC rotor shaft with a P/N other 
than P/N 30G1854, 30G3109, 30G4995, 30G4953, or 31G0014.

(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 Related Information. 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 
of the local flight standards district office/certificate holding 
district office.

(j) Related Information

    For more information about this AD, contact Mark Taylor, 
Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: (781) 238-7229; fax: (781) 238-7199; 
email: [email protected].

    Issued on May 27, 2021.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-11565 Filed 6-2-21; 8:45 am]
BILLING CODE 4910-13-P
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