[Federal Register Volume 90, Number 86 (Tuesday, May 6, 2025)]
[Rules and Regulations]
[Pages 19121-19122]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-07756]
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Rules and Regulations
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains regulatory documents
having general applicability and legal effect, most of which are keyed
to and codified in the Code of Federal Regulations, which is published
under 50 titles pursuant to 44 U.S.C. 1510.
The Code of Federal Regulations is sold by the Superintendent of Documents.
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Federal Register / Vol. 90, No. 86 / Tuesday, May 6, 2025 / Rules and
Regulations
[[Page 19121]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2024-2322; Project Identifier MCAI-2024-00065-Q;
Amendment 39-23002; AD 2025-07-01]
RIN 2120-AA64
Airworthiness Directives; Thommen Aircraft Equipment AG Digital
Air Data Computers
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; correction.
-----------------------------------------------------------------------
SUMMARY: The FAA is correcting an airworthiness directive (AD) that
published in the Federal Register. The AD applies to certain Thommen
Aircraft Equipment AG (THOMMEN) AC32 Digital Air Data Computers (ADCs).
As published, there were typographical errors in the some of the
aircraft models in the applicability table. This document corrects
those errors. In all other respects, the original document remains the
same.
DATES: This correction is effective May 15, 2025. The effective date of
AD 2025-07-01 remains May 15, 2025.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of May 15, 2025
(90 FR 15304, April 10, 2025).
ADDRESSES:
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2024-2322, or in person at Docket Operations between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD
docket contains this final rule, any comments received, and other
information. The address for Docket Operations is U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
Material Incorporated by Reference:
For THOMMEN AIRCRAFT EQUIPMENT material identified in this
AD, contact THOMMEN, Hofackerstrasse 48, 4132 Muttenz, Switzerland;
phone: +41 (0) 61 965 22 22; email: [email protected]; website:
thommen.aero.
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. It is also available at regulations.gov under
Docket No. FAA-2024-2322.
FOR FURTHER INFORMATION CONTACT: William Reisenauer, Aviation Safety
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
phone: (516) 228-7301; email: [email protected].
SUPPLEMENTARY INFORMATION: AD 2025-07-01, 39-23002 (90 FR 15304, April
10, 2025) (AD 2025-07-01) applies to certain part-numbered and serial-
numbered THOMMEN AC32 ADCs and requires removing those ADCs from
service. The ADCs are installed on, but not limited to, the aircraft
models specified in table 1 to paragraph (c)(2) of the AD.
Need for the Correction
As published, three aircraft models contained typographical errors.
Table 1 to paragraph (c)(2) of the AD referred to Airbus Helicopters
Model ``AS3323L2'' when the correct model is ``AS332L2.'' In addition,
Table 1 to paragraph (c)(2) of the AD referred to Leonardo S.p.a. Model
``A10A'' and ``1099SP'' when the correct models are ``A109A'' and
``AW109SP.'' These aircraft model errors do not affect compliance with
the AD because table 1 to paragraph (c)(2) of the AD provides some, but
not all, aircraft models on which an applicable ADC may be installed.
Material Incorporated by Reference Under 1 CFR Part 51
The FAA reviewed THOMMEN AIRCRAFT EQUIPMENT Service Bulletin SB
AC32/07, Revision 1.0, dated August 31, 2023 (THOMMEN SB AC32/07,
Revision 1.0). This material specifies procedures for determining if an
aircraft is equipped with an affected AC32 Digital ADC listed in
Appendix A, determining if the actions specified in THOMMEN SB AC32/07,
Revision 1.0, were already accomplished, and replacing any affected
THOMMEN AC32 Digital ADC.
This material is reasonably available because the interested
parties have access to it through their normal course of business or by
the means identified in the ADDRESSES section.
Correction of Publication
This document corrects three errors and correctly adds the AD as an
amendment to 14 CFR 39.13. Although no other part of the preamble or
regulatory information has been corrected, the FAA is publishing the
entire rule in the Federal Register.
The effective date of this AD remains May 15, 2025.
Since this action only corrects three typographical errors and does
not affect compliance with the AD, it has no adverse economic impact
and imposes no additional burden on any person. Therefore, the FAA has
determined that notice and public procedures are unnecessary.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends part 39 of
the Federal Aviation Regulations (14 CFR part 39) as follows:
PART 39--AIRWORTHINESS DIRECTIVES
0
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Corrected]
0
2. The FAA amends Sec. 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.
[[Page 19122]]
(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
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Airbus Defense and Space S.A. (type CN-235, CN-235-100, CN-235-200,
certificate previously held by and CN-235-300.
Construcciones Aeronauticas, S.A.).
Airbus Helicopters..................... AS332C, AS332C1, AS332L,
AS332L1, AS332L2.
Airbus Helicopters Deutschland GmbH EC635T2+.
(AHD).
Bell Textron Inc....................... 212, 412, and 412EP.
Bombardier Inc......................... CL-600-1A11 (600).
Columbia Helicopters Inc............... 107-II, 234.
General Atomics Aerotek Systems GmbH 228-100, 228-101, 228-200, 228-
(type certificate formerly held by 201, 228-202, and 228-212.
DORNIER LUFTFAHRT Inc.).
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: [email protected]. 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: [email protected].
(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: [email protected]; 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 [email protected].
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