2022-06-09: Turbine Engine Compressor Section

1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. 2. The FAA amends § 39.13 by: a. Removing Airworthiness Directive (AD) 2019-03-01, Amendment 39-19553 (84 FR 4320, February 15, 2019), and AD 2021-05-51, Amendment 39-21470 (86 FR 13445, March 9, 2021); and b. Adding the following new airworthiness directive: 2022-06-09 Pratt & Whitney Division: Amendment 39-21975; Docket No. FAA-2021-0959; Project Identifier AD-2021-00830-E. (a) Effective Date This airworthiness directive (AD) is effective April 15, 2022. (b) Affected ADs This AD replaces AD 2019-03-01, Amendment 39-19553 (84 FR 4320, February 15, 2019), and AD 2021-05-51, Amendment 39-21470 (86 FR 13445, March 9, 2021). (c) Applicability This AD applies to Pratt & Whitney Division (PW) PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 model turbofan engines, with a 1st-stage low-pressure compressor (LPC) blade, with part number 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 three in-flight failures of a 1st-stage LPC blade, with one failure resulting in an engine fire during flight, and subsequent manufacturer publication of service information specifying improved inspections for three critical locations on the 1st-stage LPC blade. The FAA is issuing this AD to prevent failure of the 1st-stage LPC blades. The unsafe condition, if not addressed, could result in 1st-stage LPC 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) Initial 1st-Stage LPC Blade Inspections (i) For 1st-stage LPC blades that have accumulated any number of cycles since new (CSN) greater than zero, before further flight after the effective date of this AD, perform a flow path and a mid span ultrasonic testing (UT) inspection of the 1st-stage LPC blades in accordance with the Accomplishment Instructions, Part A-Initial Inspection of All LPC Fan Blades Prior to Their Return to Service, paragraph 1.A. through C., of Pratt & Whitney Alert Service Bulletin (ASB) PW4G-112-A72-361, dated October 15, 2021 (PW4G-112-A72-361). New 1st-stage LPC blades that have zero CSN do not need to undergo the initial 1st-stage LPC blade flow path and mid span UT inspection required by paragraph (g)(1)(i) of this AD, but must undergo the repetitive inspections of paragraph (g)(2) of this AD. (ii) Within the following compliance times after the effective date of this AD, perform a thermal acoustic image (TAI) inspection of the 1st-stage LPC blades for cracks using a method approved by the FAA: (A) For 1st-stage LPC blades with 1,000 CSN or more, with no prior TAI inspection, inspect before further flight. (B) For 1st-stage LPC blades with 1,000 flight cycles (FCs) or more since the last TAI inspection, inspect before further flight. (C) For 1st-stage LPC blades with fewer than 1,000 CSN, with no prior TAI inspection, inspect before accumulating 1,000 CSN. (D) For 1st-stage LPC blades with fewer than 1,000 FCs since the last TAI inspection, inspect before accumulating 1,000 FCs since the last TAI inspection. Note 1 to paragraph (g)(1)(ii): The FAA-approved TAI inspection method and the vendors that can perform the FAA-approved TAI inspection are specified in the Accomplishment Instructions section and the Vendor Services section of PW4G-112-A72-361, respectively. (2) Repetitive 1st-Stage LPC Blade Inspections (i) Before exceeding 275 FCs since the last flow path UT inspection, and thereafter at intervals not exceeding 275 FCs since the last flow path UT inspection, perform a flow path UT inspection of the 1st-stage LPC blades in accordance with the Accomplishment Instructions, Part B-Repetitive Inspection of All LPC Fan Blades After Their Return to Service, paragraph 1.A., of PW4G-112-A72-361. (ii) Before exceeding 550 FCs since the last mid span UT inspection, and thereafter at intervals not exceeding 550 FCs since the last mid span UT inspection, perform a mid span UT inspection of the 1st-stage LPC blades in accordance with the Accomplishment Instructions, Part B-Repetitive Inspection of All LPC Fan Blades After Their Return to Service, paragraphs 1.B. and C., of PW4G-112-A72-361. (iii) Before exceeding 1,000 FCs since the last TAI inspection, and thereafter at intervals not exceeding 1,000 FCs since the last TAI inspection, perform repetitive TAI inspections of the 1st-stage LPC blades using a method approved by the FAA. Note 2 to paragraph (g)(2)(iii): The FAA-approved TAI inspection method and the vendors that can perform the FAA-approved TAI inspection are specified in the Accomplishment Instructions section and the Vendor Services section of PW4G-112-A72-361, respectively. (3) Removal of the 1st-Stage LPC Blade If any 1st-stage LPC blade fails any inspection required by paragraphs (g)(1) or (2) of this AD, before further flight, remove the 1st-stage LPC blade from service and replace with a part eligible for installation. (h) Definition For the purpose of this AD, a "part eligible for installation" is a new, zero CSN 1st-stage LPC blade or a 1st-stage LPC blade that has passed the inspections required by paragraphs (g)(1) and (2) of this AD, as applicable. (i) Special Flight Permit Special flight permits, as described in 14 CFR 21.197 and 21.199, are permitted provided that the actions in paragraphs (i)(1) and (2) of this AD have first been accomplished. (1) A flow path UT inspection of the 1st-stage LPC blades for cracking has been done within the last 275 FCs, as specified in the Accomplishment Instructions, Part A-Initial Inspection of All LPC Fan Blades Prior to their Return to Service, paragraph 1.A., of PW4G-112-A72-361, and the 1st-stage LPC blades have been found serviceable. This inspection is not required for 1st-stage LPC blades with 275 CSN or fewer. (2) A functional check of the left and right hydraulic pump shutoff valves to ensure they close in response to the corresponding engine fire handle input and all applicable corrective actions ( i.e., repair) within 10 days prior to flight. Note 3 to paragraph (i)(2): Guidance for accomplishing the actions required by paragraph (i)(2) of this AD can be found in the "Engine-Driven Pump (EDP) Shutoff Valve Check" (Subtasks 26-21-00-200-018, 26-21-00-200-019, 26-21-00-840-022, or Task 29-11-00-710-806) of Boeing 777-200/300 Aircraft Maintenance Manual. (j) Credit for Previous Actions This paragraph provides credit for the actions specified in paragraphs (g)(1) and (i)(1) of this AD, if those actions were performed before the effective date of this AD using the service information specified in paragraph (j)(1), (2), or (3) of this AD. (1) Paragraph 2. of the Accomplishment Instructions of Pratt & Whitney Special Instruction No. 85F21, dated May 12, 2021, for a flow path UT inspection. (2) Paragraph 1.a) through c) of the Accomplishment Instructions of Pratt & Whitney Special Instruction No. 130F-21, dated July 1, 2021, for a flow path and a mid span UT inspection. (3) Paragraph 2.a) through c) of the Accomplishment Instructions of Pratt & Whitney Special Instruction No. 130F-21, Revision A, dated July 28, 2021, for a flow path and a mid span UT inspection. (k) 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 (l) of this AD. 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. (l) Related Information For more information about this AD, contact Carol Nguyen, Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: (781) 238-7655; fax: (781) 238-7199; email: carol.nguyen@faa.gov. (m) 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) Pratt & Whitney Alert Service Bulletin PW4G-112-A72-361, dated October 15, 2021. (ii) [Reserved] (3) For service information identified in this AD, contact Pratt & Whitney Division, 400 Main Street, East Hartford, CT 06118; phone: (860) 565-0140; email: help24@prattwhitney.com; website: https://connect.prattwhitney.com. (4) You may view this service information 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. (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: fr.inspection@nara.gov, or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html. Issued on March 4, 2022. Lance T. Gant, Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2022-05296 Filed 3-9-22; 4:15 pm]BILLING CODE 4910-13-P