2024-04-09: Instruments

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: 2024-04-09 The Boeing Company: Amendment 39-22688; Docket No. FAA-2022-0598; Project Identifier AD-2021-01322-T. (a) Effective Date This airworthiness directive (AD) is effective April 23, 2024. (b) Affected ADs None. (c) Applicability This AD applies to The Boeing Company Model 777-200, 777-200LR, 777-300, 777-300ER, and 777F series airplanes, certificated in any category, as identified in Boeing Alert Requirements Bulletin 777-31A0342 RB, dated July 19, 2021. (d) Subject Air Transport Association (ATA) of America Code 31, Instruments. (e) Unsafe Condition This AD was prompted by reports of wing anti-ice (WAI) valve failure that can result in undetected structural damage to leading edge (LE) slat assemblies, and separately a failure of the autothrottle (A/T) to disconnect after the pilot manually advanced the throttle levers disconnect after the pilot manually advanced the throttle levers, which caused a low-speed condition during a go-around. This AD was also prompted by a determination that insufficient low-speed protection exists in the 777 fleet and a determination that the flightcrew may not recognize and properly respond to a multi-channel unreliable airspeed event. The FAA is issuing this AD to prevent undetected failure of the WAI system and consequent high temperature bleed air flowing into the LE slat assemblies, which could result in reduced structural integrity of the slat and prevent continued safe flight and landing of the airplane. The FAA is also issuing this AD to prevent failure of the A/T to disconnect after manually advancing the throttle levers, or insufficient low energy protection, which could result in controlled flight into terrain, or a multi-channel unreliable airspeed event could result in loss of control of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions Except as specified by paragraph (h) of this AD: At the applicable times specified in the "Compliance" paragraph of Boeing Alert Requirements Bulletin 777-31A0342 RB, dated July 19, 2021, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Alert Requirements Bulletin 777-31A0342 RB, dated July 19, 2021. Note 1 to paragraph (g): Guidance for accomplishing the actions required by this AD can be found in Boeing Alert Service Bulletin 777-31A0342, dated July 19, 2021, which is referred to in Boeing Alert Requirements Bulletin 777-31A0342 RB, dated July 19, 2021. (h) Exceptions to Service Information Specifications (1) Where the Compliance Time columns of the tables in the "Compliance" paragraph of Boeing Alert Requirements Bulletin 777-31A0342 RB, dated July 19, 2021, use the phrase "the original issue date of Requirements Bulletin 777-31A0342 RB," this AD requires using the effective date of this AD. (2) Where Boeing Alert Requirements Bulletin 777-31A0342 RB, dated July 19, 2021, specifies contacting Boeing for instructions for upgrading certain software: This AD requires doing the upgrade using a method approved in accordance with the procedures specified in paragraph (i) of this AD. (3) Where the description in the Effectivity section of Boeing Alert Requirements Bulletin 777-31A0342 RB, dated July 19, 2021, defines Group 1 airplanes as "Airplanes with Airplane Information Management System (AIMS)-2 with service bulletin 777-31-0294 incorporated," this AD requires using "Airplanes with Airplane Information Management System (AIMS)-2 with a requirement to incorporate service bulletin 777-31-0294." (4) Where the description in the Effectivity section of Boeing Alert Requirements Bulletin 777-31A0342 RB, dated July 19, 2021, defines Group 2 airplanes as "Airplanes with AIMS-2 with service bulletin 777-31-0331 incorporated," this AD requires using "Airplanes with AIMS-2 with a requirement to incorporate service bulletin 777-31-0331." (5) Where the description in the Effectivity section of Boeing Alert Requirements Bulletin 777-31A0342 RB, dated July 19, 2021, defines Group 3 airplanes as "Airplanes with AIMS-2 with service bulletin 777-31-0332 incorporated," this AD requires using "Airplanes with AIMS-2 with a requirement to incorporate service bulletin 777-31-0332." (6) Where the description in the Effectivity section of Boeing Alert Requirements Bulletin 777-31A0342 RB, dated July 19, 2021, defines Group 5 airplanes as "Airplanes with Airplane Information Management System (AIMS)-," this AD requires using "Airplanes with Airplane Information Management System (AIMS)-1 and airplanes equipped with AIMS-2 that are not in Group 1, 2, 3, or 4." (That is, there are two subsets of Group 5 airplanes with different required actions.) For airplanes, that, as of the effective date of this AD, are equipped with AIMS-2 and are not in Group 1, 2, 3 or 4, this AD does not require Action 1 of Table 3 of the Accomplishment Instructions of Boeing Alert Requirements Bulletin 777-31A0342 RB, dated July 19, 2021. (i) Alternative Methods of Compliance (AMOCs) (1) The Manager, AIR-520, Continued Operational Safety 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 (j)(1) 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 Organization Designation Authorization (ODA) that has been authorized by the Manager, AIR-520, Continued Operational Safety 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. (j) Related Information (1) For more information about this AD, contact Doug Tsuji, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3548; email: [email protected]. (2) Service information identified in this AD that is not incorporated by reference is available at the addresses specified in paragraphs (k)(3) and (4) of this AD. (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. (i) Boeing Alert Requirements Bulletin 777-31A0342 RB, dated July 19, 2021. (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 material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email [email protected]. Issued on February 21, 2024. Victor Wicklund, Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2024-05497 Filed 3-18-24; 8:45 am]BILLING CODE 4910-13-P