2023-06-10: Ice and Rain Protection, Powerplant

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 adding the following new airworthiness directive: 2023-06-10 The Boeing Company: Amendment 39-22396; Docket No. FAA-2023-0440; Project Identifier AD-2023-00245-T. (a) Effective Date This airworthiness directive (AD) is effective April 11, 2023. (b) Affected ADs None. (c) Applicability This AD applies to all The Boeing Company Model 737-8, -8200, and -9 airplanes, certificated in any category. (d) Subject Air Transport Association (ATA) of America Code 30, Ice and Rain Protection; 71, Powerplant. (e) Unsafe Condition This AD was prompted by a report indicating that certain engine anti-ice (EAI) exhaust duct fasteners were inadequately torqued during installation at the factory. The FAA is issuing this AD to address loose or missing fasteners for the EAI exhaust duct that may allow EAI exhaust air to enter the inlet inner barrel causing heat damage that will compromise the structural integrity of the inlet, eventually leading to inlet failure and separation under normal flight loads. The unsafe condition, if not addressed, will lead to failure of the corresponding engine due to airflow disruption and ingestion of debris and likely failure and separation of the associated fan cowl. Damage to the engine and engine nacelle could result in a loss of engine thrust, increased nacelle drag, and disruption of airflow over the wing, which may excessively reduce the controllability and climb performance of the airplane; and damage from debris departing the engine and nacelle, which could impact the fuselage and empennage, could result in personal injury to passengers and loss of control of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions For airplanes with an original airworthiness certificate or original export certificate of airworthiness issued on or before the effective date of the AD: Except as specified by paragraph (h) of this AD, at the applicable times specified in the "Suggested Operator Action" section of Boeing Service Letter 737-SL-71-081-A, Revision A, dated March 3, 2023, do all applicable actions identified as "RC" (required for compliance) in, and in accordance with, the Work Instructions of Boeing Service Letter 737-SL-71-081-A, Revision A, dated March 3, 2023. Perform all applicable related investigative and corrective actions before further flight. (h) Exceptions to Service Information Specifications (1) Where the "Suggested Operator Action" section of Boeing Service Letter 737-SL-71-081-A, Revision A, dated March 3, 2023, specifies doing "the following actions within the given time from the publication of this service letter," this AD requires accomplishing the actions within the specified compliance times after "the effective date of this AD." (2) Where the "Suggested Operator Action" section of Boeing Service Letter 737-SL-71-081-A, Revision A, dated March 3, 2023, specifies "corrective actions," for this AD, those actions include "corrective and related investigative actions." (3) A review of airplane maintenance records is acceptable in lieu of the inspection to verify the serial number of the inlet specified in step A.1. of the Work Instructions of Boeing Service Letter 737-SL-71-081-A, Revision A, dated March 3, 2023, if the serial number of the inlet can be conclusively determined from that review. (4) Where Boeing Service Letter 737-SL-71-081-A, Revision A, dated March 3, 2023, specifies contacting Boeing for repair or further instructions: This AD requires doing the repair and applicable instructions before further flight using a method approved in accordance with the procedures specified in paragraph (l) of this AD. (5) Where the Work Instructions of Boeing Service Letter 737-SL-71-081-A, Revision A, dated March 3, 2023, refers to the structural repair manual, replace the text "737-8/8200/9 Structural Repair Manual (SRM) 51-40-04, Revision 18/9/15," with "737-8 Structural Repair Manual (SRM) 51-40-04, Revision 18 or 19; 737-8200 SRM 51-40-04, Revision 9 or 10; or 737-9 SRM 51-40-04, Revision 15 or 16." (i) Parts Installation Limitation As of the effective date of this AD, no person may install an engine inlet assembly with a serial number listed in Attachment I of Boeing Service Letter 737-SL-71-081-A, Revision A, dated March 3, 2023, on any airplane unless all applicable actions required by paragraph (g) of this AD have been done for that inlet. (j) Credit for Previous Actions This paragraph provides credit for the actions specified in paragraph (g) of this AD, if those actions were performed before the effective date of this AD using Boeing Service Letter 737-SL-71-081, dated February 20, 2023, provided the conditions specified in paragraphs (j)(1) and (2) of this AD are met. (1) An inspection or records review has been done to verify the inlet serial number is not included in the additional serial numbers identified in Attachment I of Boeing Service Letter 737-SL-71-081-A, Revision A, dated March 3, 2023; and the serial number of the inlet can be conclusively determined from that inspection or review. (2) Where the Work Instructions of Boeing Service Letter 737-SL-71-081, dated February 20, 2023, refer to the structural repair manual (SRM) to apply torque, the applicable SRM identified in paragraph (j)(2)(i), (ii), or (iii) of this AD was used to apply the torque. (i) Boeing 737-8 SRM 51-40-04, Revision 18, dated November 10, 2022; or Revision 19, dated March 10, 2023. (ii) Boeing 737-8200 SRM 51-40-04, Revision 9, dated November 10, 2022; or Revision 10, dated March 10, 2023. (iii) Boeing 737-9 SRM 51-40-04, Revision 15, dated November 10, 2022; or Revision 16, dated March 10, 2023. (k) Special Flight Permit (1) Special flight permits, as described in 14 CFR 21.197 and 21.199, may be issued to move the airplane to a maintenance facility prior to performing the required inspections. (2) If, during the inspections required by paragraph (g) of this AD, only one engine is found with an inlet having any crack or thermal damage: Special flight permits, as described in 14 CFR 21.197 and 21.199, may be issued to operate the airplane to a location where the requirements of this AD can be accomplished provided the conditions specified in paragraph (k)(2)(i) and (ii) of this AD, as applicable, are met. (i) The EAI is deactivated on the affected engine in accordance with the operator's existing Minimum Equipment List. (ii) For any inlet with any thermal exposure ( i.e., heat damage) on the inner barrel, The Boeing Company Organization Designation Authorization (ODA) is contacted to obtain concurrence for issuance of a special flight permit and The Boeing Company ODA concurs. Operators must comply with any flight limitations provided by The Boeing Company ODA. The concurrence with any limitations must specifically refer to this AD. (3) If, during the inspections required by paragraph (g) of this AD, both engines are found with inlets having any crack or thermal exposure: Special flight permits, as described in 14 CFR 21.197 and 21.199, are not allowed. (l) Alternative Methods of Compliance (AMOCs) (1) The Manager, Seattle ACO 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 responsible Flight Standards 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 (m) of this AD. 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 responsible Flight Standards Office. (3) An AMOC that provides an acceptable level of safety may be used for any repair, modification, or alteration required by this AD if it is approved by The Boeing Company ODA that has been authorized by the Manager, Seattle ACO Branch, FAA, to make those findings. To be approved, the repair method, modification deviation, or alteration deviation must meet the certification basis of the airplane, and the approval must specifically refer to this AD. (4) Except as required by paragraph (h) of this AD: For service information that contains steps that are labeled as Required for Compliance (RC), the provisions of paragraphs (l)(4)(i) and (ii) of this AD apply. (i) The steps labeled as RC, including substeps under an RC step and any figures identified in an RC step, must be done to comply with the AD. If a step or substep is labeled "RC Exempt," then the RC requirement is removed from that step or substep. An AMOC is required for any deviations to RC steps, including substeps and identified figures. (ii) Steps not labeled as RC may be deviated from using accepted methods in accordance with the operator's maintenance or inspection program without obtaining approval of an AMOC, provided the RC steps, including substeps and identified figures, can still be done as specified, and the airplane can be put back in an airworthy condition. (m) Related Information For more information about this AD, contact Samuel Dorsey, Aerospace Engineer, Propulsion Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3415; email: [email protected]. (n) 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) Boeing Service Letter 737-SL-71-081-A, Revision A, dated March 3, 2023. Note 1 to paragraph (n)(2)(i): Attachments I and II of this document are dated March 2, 2023. (ii) [Reserved] (3) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone 562-797-1717; website myboeingfleet.com. (4) You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195. (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 protected], or go to: www.archives.gov/federal-register/cfr/ibr-locations.html. Issued on March 17, 2023. Christina Underwood, Acting Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2023-06364 Filed 3-23-23; 4:15 pm]BILLING CODE 4910-13-P