2023-11-07: Ground Proximity System

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: a. Removing Airworthiness Directive (AD) 2021-23-13, Amendment 39-21811 (86 FR 69992, December 9, 2021), and b. Adding the following new AD: 2023-11-07 Various Helicopters: Amendment 39-22453; Docket No. FAA-2023-0668; Project Identifier AD-2023-00199-R. (a) Effective Date This airworthiness directive (AD) is effective June 22, 2023. (b) Affected ADs This AD replaces AD 2021-23-13, Amendment 39-21811 (86 FR 69992, December 9, 2021) (AD 2021-23-13). (c) Applicability This AD applies to all helicopters, certificated in any category, equipped with a radio (also known as radar) altimeter. These radio altimeters are installed on various helicopter models including, but not limited to, the helicopters for which the design approval holder is identified in paragraphs (c)(1) through (20) of this AD. (1) Airbus Helicopters (2) Airbus Helicopters Deutschland GmbH (3) Air Space Design and Manufacturing, LLC (4) Bell Textron Canada Limited (5) Bell Textron Inc. (6) Brantly International, Inc. (7) Centerpointe Aerospace Inc. (8) Columbia Helicopters, Inc. (9) The Enstrom Helicopter Corporation (10) Erickson Air-Crane Incorporated, DBA Erickson Air-Crane (11) Helicopteres Guimbal (12) Siam Hiller Holdings, Inc. (13) Kaman Aerospace Corporation (14) Leonardo S.p.a. (15) MD Helicopters Inc. (16) PZL Swidnik S.A. (17) Robinson Helicopter Company (18) Schweizer RSG LLC (19) Scotts-Bell 47 Inc. (20) Sikorsky Aircraft Corporation (d) Subject Air Transport Association (ATA) of America Code 3444, Ground Proximity System. (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). The FAA is issuing this AD because radio altimeter anomalies that are undetected by the automation or pilot, particularly close to the ground, could lead to loss of continued safe flight and landing. (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 rotorcraft" 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 rotorcraft. (i) Tolerance to radio altimeter interference, for the fundamental emissions (3.7-3.8 GHz), at or above the power spectral density (PSD) curve threshold specified in figure 1 to paragraph (g)(1)(i) of this AD. Figure 1 to paragraph (g)(1)(i)- Fundamental Effective Isotropic PSD at Outside Interface of Rotorcraft Antenna BILLING CODE 4910-13-P ER22JN23.005 (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. Figure 2 to paragraph (g)(1)(ii): Spurious Effective Isotropic PSD at Outside Interface of Rotorcraft Antenna ER22JN23.006 (2) For purposes of this AD, a "non-radio altimeter tolerant rotorcraft" 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) Retained Rotorcraft Flight Manual (RFM) Revision for Non-Radio Altimeter Tolerant Rotorcraft For non-radio altimeter tolerant rotorcraft: On or before January 4, 2022, revise the Limitations Section of the existing RFM for your helicopter by incorporating the limitations specified in figure 3 to paragraph (h) of this AD. This may be done by inserting a copy of this AD into the existing RFM for your helicopter. The action required by this paragraph may be performed by the owner/operator (pilot) holding at least a private pilot certificate and must be entered into the aircraft records showing compliance with this AD in accordance with 14 CFR 43.9(a)(1) through (4) and 14 CFR 91.417(a)(2)(v). The record must be maintained as required by 14 CFR 91.417 or 14 CFR 135.439. Figure 3 to paragraph (h)- RFM Revision ER22JN23.007 (i) RFM Revision for Non-Radio Altimeter Tolerant Rotorcraft For non-radio altimeter tolerant rotorcraft, 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 RFM for your helicopter by including the information specified in figure 4 to paragraph (i) of this AD. This may be done by inserting a copy of this AD into the existing RFM for your helicopter. The action required by this paragraph may be performed by the owner/operator (pilot) holding at least a private pilot certificate and must be entered into the aircraft records showing compliance with this AD in accordance with 14 CFR 43.9(a)(1) through (4) and 14 CFR 91.417(a)(2)(v). The record must be maintained as required by 14 CFR 91.417 or 14 CFR 135.439. Incorporating the RFM revision required by this paragraph terminates the RFM revision required by paragraph (h) of this AD. (2) Before further flight after incorporating the limitations specified in figure 4 to paragraph (i) of this AD, remove the RFM revision required by paragraph (h) of this AD. Figure 4 to paragraph (i)- RFM Revision for Non-Radio Altimeter Tolerant Rotorcraft ER22JN23.008 (j) Terminating Action for RFM Limitations (1) Modifying the rotorcraft from a non-radio altimeter tolerant rotorcraft to a radio altimeter tolerant rotorcraft terminates the limitations in paragraph (i) of this AD for that rotorcraft. (2) After modifying the rotorcraft to a radio altimeter tolerant rotorcraft, the limitations specified by paragraph (i) of this AD may be removed from the RFM. (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: 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) AMOCs approved for AD 2021-23-13 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 David Swartz, Continued Operational Safety Technical Advisor, COS Program Management Section, Operational Safety Branch, FAA; phone: 817-222-5390; email: operationalsafety@faa.gov. (m) Material Incorporated by Reference None. Issued on June 15, 2023. Michael Linegang, Acting Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2023-13319 Filed 6-16-23; 4:15 pm]BILLING CODE 4910-13-P