2023-12-14: Navigation

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) 2022-06-16, Amendment 39-21982 (87 FR 14780, March 16, 2022), and b. Adding the following new AD: 2023-12-14 The Boeing Company: Amendment 39-22472; Docket No. FAA-2023-0922; Project Identifier AD-2022-01431-T. (a) Effective Date This airworthiness directive (AD) is effective June 21, 2023. (b) Affected ADs This AD replaces AD 2022-06-16, Amendment 39-21982 (87 FR 14780, March 16, 2022) (AD 2022-06-16). (c) Applicability This AD applies to all The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, and 747-400F series airplanes, certificated in any category. (d) Subject Air Transport Association (ATA) of America Code 34, Navigation. (e) Unsafe Condition This AD was prompted by a 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 C-Band), and a determination that during takeoff, approach, landings, and go-arounds, as a result of this interference, certain airplane systems may not properly function, resulting in increased flightcrew workload while on approach with the flight director, autothrottle, or autopilot engaged. The FAA is issuing this AD to address 5G C-Band interference that could result in increased flightcrew workload and could lead to reduced ability of the flightcrew to maintain safe flight and landing of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Definitions (1) For purposes of this AD, a "5G C-Band mitigated airport" (5G CMA) is an airport at which the telecommunications companies have agreed to voluntarily limit their 5G deployment at the request of the FAA, as identified by an FAA Domestic Notice. (2) 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)(2)(i) and (ii) of this AD, using a method approved by the FAA. (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)(2)(i) of this AD. BILLING CODE 4910-13-P Figure 1 to paragraph (g)(2)(i)- Fundamental Effective Isotropic PSD at Outside Interface of Aircraft Antenna ER21JN23.072 (ii) Tolerance to radio altimeter interference, for the spurious emissions (3.7-3.98 GHz), at or above the PSD curve threshold specified in figure 2 to paragraph (g)(2)(ii) of this AD. Figure 2 to paragraph (g)(2)(ii)- Spurious Effective Isotropic PSD at Outside Interface of Aircraft Antenna ER21JN23.073 (3) 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)(2)(i) and (ii) of this AD. (h) Retained Airplane Flight Manual (AFM) Revision This paragraph restates the requirements of paragraph (h) of AD 2022-02-16. (1) Within 2 days after March 16, 2022 (the effective date of AD 2022-06-16): Revise the Limitations Section of the existing AFM to include the information specified in figure 3 to paragraph (h)(1) of this AD. This may be done by inserting a copy of figure 3 to paragraph (h)(1) of this AD into the existing AFM. Figure 3 to paragraph (h)(1)- AFM Limitations Revision ER21JN23.074 (2) Within 2 days after March 16, 2022 (the effective date of AD 2022-06-16): Revise the Operating Procedures Section of the existing AFM to include the information specified in figure 4 to paragraph (h)(2) of this AD. This may be done by inserting a copy of figure 4 to paragraph (h)(2) of this AD into the existing AFM. Figure 4 to paragraph (h)(2)- AFM Operating Procedures Revision ER21JN23.075 (i) New Requirement: AFM Revision for Non-Radio Altimeter Tolerant Airplanes For non-radio altimeter tolerant airplanes, do the actions specified in paragraphs (i)(1) and (2) of this AD. (1) On or before June 30, 2023, revise the Limitations Section of the existing AFM to include the information specified in figure 5 to paragraph (i) of this AD. This may be done by inserting a copy of figure 5 to paragraph (i) of this AD into the existing AFM. Incorporating the AFM revision required by this paragraph terminates the AFM revision required by paragraph (h)(1) of this AD. (2) Before further flight after incorporating the limitations specified in figure 5 to paragraph (i) of this AD, remove the AFM revision required by paragraph (h)(1) of this AD. Figure 5 to paragraph (i)- AFM Revision for Non-Radio Altimeter Tolerant Airplanes ER21JN23.076 (j) New Requirement: AFM Revision for Radio Altimeter Tolerant Airplanes For radio altimeter tolerant airplanes, do the actions specified in paragraphs (j)(1) and (2) of this AD. (1) On or before June 30, 2023, revise the Limitations Section of the existing AFM to include the information specified in figure 6 to paragraph (j) of this AD. This may be done by inserting a copy of figure 6 to paragraph (j) of this AD into the existing AFM. Incorporating the AFM revision required by this paragraph terminates the AFM revision required by paragraph (h)(1) of this AD. (2) Before further flight after incorporating the limitations specified in figure 6 to paragraph (j) of this AD, remove the AFM revision required by paragraph (h)(1) of this AD. Figure 6 to paragraph (j)- AFM Revision for Radio Altimeter Tolerant Airplanes ER21JN23.077 (k) Alternative Methods of Compliance (AMOCs) (1) The Manager, 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 Operational Safety Branch, send it to the attention of the person identified in paragraph (l) 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) AMOCs approved for AD 2021-23-12, Amendment 39-21810 (86 FR 69984, December 9, 2021), providing relief for specific radio altimeter installations are approved as AMOCs for the requirements specified in paragraph (h) of this AD until June 30, 2023. (l) Related Information For more information about this AD, contact Brett Portwood, Continued Operational Safety Technical Advisor, COS Program Management Section, Operational Safety Branch, FAA, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 817-222-5390; email: [email protected] . (m) Material Incorporated by Reference None. Issued on June 9, 2023. Michael Linegang, Acting Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2023-13149 Filed 6-16-23; 11:15 am]BILLING CODE 4910-13-P