2026-13-02: Navigation

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: 2026-13-02 Transport and Commuter Category Airplanes: Amendment 39-23384; Docket No. FAA-2026-4659; Project Identifier MCAI-2025-00826-A,T. (a) Effective Date This airworthiness directive (AD) is effective July 1, 2026. (b) Affected ADs None. (c) Applicability This AD applies to all transport and commuter category airplanes equipped with a radio (also known as radar) altimeter. These radio altimeters are installed on various transport and commuter category airplanes including, but not limited to, the airplanes for which the design approval holder is identified in paragraphs (c)(1) through (18) of this AD. (1) Airbus Canada Limited Partnership (2) Airbus SAS (3) ATR-GIE Avions de Transport Régional (4) BAE Systems (Operations) Limited (5) Bombardier Inc. (6) Dassault Aviation (7) De Havilland Aircraft of Canada Limited (8) Embraer S.A. (including type certificates previously held by Yaborã Indústria Aeronáutica S.A., which are now held by Embraer S.A.) (9) Fokker Services B.V. (10) Gulfstream Aerospace Corporation (11) Gulfstream Aerospace LP (12) Lockheed Martin Corporation/Lockheed Martin Aeronautics Company (13) MHI RJ Aviation ULC (14) Pilatus Aircraft Limited (15) Saab AB, Support and Services (16) Textron Aviation Inc. (17) The Boeing Company (18) Viking Air Limited (d) Subject Air Transport Association (ATA) of America Code 31, Indicating/Recording System; 34, Navigation. (e) Unsafe Condition This AD was prompted by the determination that radio altimeters cannot be relied upon to perform their intended function if they experience interference from wireless broadband operations in the 3.7-3.98 GHz frequency band (5G Lower C-Band), when operating in Canadian airspace. The FAA is issuing this AD because radio altimeter anomalies that are undetected by the automation or pilot, particularly close to the ground ( e.g., landing flare), could lead to loss of continued safe flight and landing. Additionally, radio altimeter anomalies could lead to increased flightcrew workload and flightcrew desensitization to warnings. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Definitions (1) For purposes of this AD, a "radio altimeter tolerant airplane" is one for which the radio altimeter, as installed, demonstrates the tolerances specified in paragraphs (g)(1)(i) and (ii) of this AD, using a method approved by the FAA. No actions are required by this AD for radio altimeter tolerant airplanes. (i) Tolerance to radio altimeter interference, for the fundamental emissions (3.7-3.98 GHz), at or above the power spectral density (PSD) curve threshold specified in figure 1 to paragraph (g)(1)(i) of this AD. ER30JN26.003 (ii) Tolerance to radio altimeter interference, for the spurious emissions (4.2-4.4 GHz), at or above the PSD curve threshold specified in figure 2 to paragraph (g)(1)(ii) of this AD. ER30JN26.004 (2) For purposes of this AD, a "non-radio altimeter tolerant airplane" is one for which the radio altimeter, as installed, does not demonstrate the tolerances specified in paragraphs (g)(1)(i) and (ii) of this AD. (h) Airplane Flight Manual (AFM) Revision For non-radio altimeter tolerant airplanes: Before further flight in Canadian airspace, revise the Limitations Section of the existing AFM to include the information specified in figure 3 to paragraph (h) of this AD. This may be done by inserting a copy of figure 3 to paragraph (h) of this AD into the existing AFM. ER30JN26.009 (i) Terminating Action for AFM Limitations (1) Modifying the airplane from a non-radio altimeter tolerant airplane to a radio altimeter tolerant airplane terminates the limitations in paragraph (h) of this AD for that airplane. (2) After modifying the airplane to a radio altimeter tolerant airplane, the limitations specified by paragraph (h) of this AD may be removed from the AFM. (j) Alternative Methods of Compliance (AMOCs) (1) The Manager, AIR-720, 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 AIR-720, Operational Safety Branch, send it to the attention of the person identified in paragraph (k) of this AD and email to: AMOC@faa.gov . (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) The following AMOCs approved previously for AD 2023-10-02, Amendment 39-22438 (88 FR 34065, May 26, 2023) are approved as AMOCs for paragraph (g)(1) of this AD: FAA AMOC letters 720-23-00133, 720-23-00137, 720-23-00138, 720-23-00155, 720-23-00158, 720-23-00169, 720-23-00191, 720-23-00192, 720-24-00012, 720-25-00025, 720-25-00031, 720-26-00009, 722-23-00073, 722-23-00076, and 756-25-00100. (k) Additional Information For more information about this AD, contact Ken Fairhurst, Continued Operational Safety Technical Advisor, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 817-222-5390; email: operationalsafety@faa.gov. (l) Material Incorporated by Reference None. Issued on June 23, 2026. Christopher R. Parker, Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2026-13162 Filed 6-26-26; 4:15 pm]BILLING CODE 4910-13-P