2025-07-01: Air Data Computer

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 airworthiness directive: 2025-07-01 Thommen Aircraft Equipment AG: Amendment 39-23002; Docket No. FAA-2024-2322; Project Identifier MCAI-2024-00065-Q. (a) Effective Date This airworthiness directive (AD) is effective May 15, 2025. (b) Affected ADs None. (c) Applicability (1) This AD applies to Thommen Aircraft Equipment AG (THOMMEN) AC32 Digital Air Data Computers (ADCs) having an affected part as defined in paragraph (f)(1) of this AD. (2) This appliance is installed on, but not limited to, the following aircraft models specified in table 1 to paragraph (c)(2) of this AD, certificated in any category. Table 1 to Paragraph (c)(2) -Applicable Aircraft Models Type certificate holder Aircraft model Airbus Defense and Space S.A. (type certificate previously held by Construcciones Aeronauticas, S.A.) CN-235, CN-235-100, CN-235-200, and CN-235-300. Airbus Helicopters AS332C, AS332C1, AS332L, AS332L1, AS332L2. Airbus Helicopters Deutschland GmbH (AHD) EC635T2+. Bell Textron Inc 212, 412, and 412EP. Bombardier Inc CL-600-1A11 (600). Columbia Helicopters Inc 107-II, 234. General Atomics Aerotek Systems GmbH (type certificate formerly held by DORNIER LUFTFAHRT Inc.) 228-100, 228-101, 228-200, 228-201, 228-202, and 228-212. Gulfstream Aerospace LP Westwind Astra 1124 (serial numbers 004-0410). International Air Response C-130A. Kawasaki Heavy Industries, Limited KV107-II. Leonardo S.p.a A109, A109A, A109A II, A109C, A109K2, A109S, AW109SP, AW139, and AW189. Textron Aviation Inc 200, 300, 500, 501, 550, and 551. Viking Air Limited CL-215-6B11 (CL-215T Variant). (3) This appliance is approved for installation and could be installed on various aircraft modified by Supplemental Type Certificate (STC) No. SR09595RC or ST01523WI. (d) Subject Joint Aircraft System Component (JASC) Code 3417, Air Data Computer. (e) Unsafe Condition This AD was prompted by occurrences of AC32 Digital ADCs that stopped functioning due to the power module failing at temperatures below ?20 degrees Celsius. The unsafe condition, if not addressed, could result in insufficient navigational data provided to the flight crew, resulting in reduced control of the aircraft. (f) Definitions For the purpose of this AD the definitions in paragraphs (f)(1) through (4) of this AD apply: (1) Affected part: THOMMEN AC32 Digital ADCs, part numbers (P/N) AC32.10.21.10.XX, AC32.10.21.11.XX, AC32.11.21.10.XX, and AC32.11.21.11.XX (where XX represents any alpha/numerical sequence), and having a serial number (S/N) listed in Appendix A of THOMMEN AIRCRAFT EQUIPMENT Service Bulletin SB AC32/07, Revision 1.0, dated August 31, 2023 (THOMMEN SB AC32/07 Revision 1.0). (2) Serviceable part: Any AC32.(X) Digital ADC that is not an affected part; or an affected part where the power module has been replaced by THOMMEN, in accordance with the instructions of THOMMEN SB AC32/07 Revision 1.0. (3) Group 1 aircraft: Have an affected part installed. (4) Group 2 aircraft: Do not have an affected part installed but are eligible for AC32.(X) Digital ADC installation. (g) Compliance Comply with this AD within the compliance times specified, unless already done. (h) Required Actions For Group 1 aircraft: Within 12 months after the effective date of this AD, remove each affected part from service and replace it with a serviceable part in accordance with paragraph 3.A. of the Accomplishment Instructions in THOMMEN SB AC32/07 Revision 1.0, except where this material specifies to send the removed affected part to the manufacturer, this AD does not require that action. (i) Parts Installation Prohibition For Group 1 and 2 aircraft: As of the effective date of this AD, do not install an affected part on any aircraft. (j) Special Flight Permits A one-time special flight permit may be issued in accordance with 14 CFR 21.197 and 21.199 in order to fly to a maintenance base to perform the required action in this AD, provided a flight profile above ?15 degrees Celsius (5 degrees Fahrenheit) is maintained. (k) Alternative Methods of Compliance (AMOCs) (1) The Manager, International Validation 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 local Flight Standards District Office, as appropriate. If sending information directly to the International Validation Branch, send it to the attention of the person identified in paragraph (l) of this AD and email to: AMOC@faa.gov. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office. (l) Additional Information For more information about this AD, contact William Reisenauer, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (516) 228-7301; email: 9-AVS-AIR-BACO-COS@faa.gov. (m) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference of the material listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this material as applicable to do the actions required by this AD, unless the AD specifies otherwise. (3) The following material was approved for IBR on May 15, 2015 (90 FR 15304, April 10, 2025). (i) Thommen Aircraft Equipment Service Bulletin SB AC32/07, Revision 1.0, dated August 31, 2023. (ii) [Reserved] (4) For Thommen Aircraft Equipment material in this AD, contact THOMMEN, Hofackerstrasse 48, 4132 Muttenz, Switzerland; phone: +41 (0) 61 965 22 22; email: sales@thommen.aero; website: thommen.aero . (5) You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 901 Locust, Kansas City, MO 64106. For information on the availability of this material at the FAA, call (817) 222-5110. (6) 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 fr.inspection@nara.gov . Issued on April 29, 2025. Steven W. Thompson, Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2025-07756 Filed 5-5-25; 8:45 am]BILLING CODE 4910-13-P