(a) EFFECTIVE DATE

    This airworthiness directive (AD) is effective June 18, 2025.

(b) AFFECTED ADS

    None.

(c) APPLICABILITY

    This AD applies to all MHI RJ Aviation ULC (Type Certificate previous-
    ly held by Bombardier, Inc.)  Model  CL-600-2C10  (Regional Jet Series
    700, 701 & 702),  CL-600-2C11  (Regional Jet Series 550),  CL-600-2D15
    (Regional Jet Series 705),  CL-600-2D24 (Regional Jet Series 900), and
    CL-600-2E25 (Regional Jet Series 1000) airplanes,  certificated in any
    category.

(d) SUBJECT

    Air Transport Association (ATA) of America Code 23, Communications.

(e) UNSAFE CONDITION

    This AD was prompted by reports  that  a  cockpit voice recorder (CVR)
    impact switch was installed in the wrong direction.  The impact switch
    disables power to the CVR in the event of an accident to prevent over-
    writing cockpit recordings.  The FAA is issuing  this AD to address an
    incorrectly installed impact switch,  which  could  result  in loss of
    data that could hinder  the identification  of the unsafe condition in
    the event of an accident  and  consequently  impede the development of
    actions to address the unsafe condition that caused the accident.

(f) COMPLIANCE

    Comply with this AD within the compliance times specified,  unless al-
    ready done.

(g) REQUIREMENTS

    Except as specified  in paragraph (h) of this AD:  Comply with all re-
    quired actions and compliance times specified in,  and  in  accordance
    with, Transport Canada AD CF-2024-35 dated October 16, 2024 (Transport
    Canada AD CF-2024-35).

(h) EXCEPTIONS TO TRANSPORT CANADA AD CF-2024-35

(1) Where Transport Canada AD CF-2024-35  refers  to  its  effective date,
    this AD requires using the effective date of this AD.

(2) Where paragraph A. of Transport Canada AD CF-2024-35 specifies to "in-
    spect the installation  of the impact switch  P/N 3L0-453-2 in accord-
    ance with the MHIRJ AMM task 23-71-10-400-801  to  confirm  the  reset
    switch faces forward," this AD requires replacing that text with "per-
    form a general visual inspection  of  the  installation  of the impact
    switch P/N 3L0-453-2 to confirm the reset switch faces forward."

(3) Where paragraph B. of Transport Canada AD CF-2024-35 specifies correc-
    tive action,  this AD requires that the corrective action be performed
    before further flight  after finding  any impact switch  that does not
    face forward.

(i) ADDITIONAL AD PROVISIONS

    The following provisions also apply to this AD:

(1) Alternative Methods of Compliance (AMOCs):  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
    responsible Flight Standards Office, as appropriate. If sending infor-
    mation directly to the manager of the International Validation Branch,
    send it to the attention of the person  identified in paragraph (j) 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.

(2) Contacting the Manufacturer:  For any requirement in this AD to obtain
    instructions from a manufacturer,  the  instructions  must  be  accom-
    plished using a method approved by the Manager,  International Valida-
    tion Branch, FAA; or Transport Canada; or MHI RJ Aviation ULC's Trans-
    port Canada Design Approval Organization (DAO). If approved by the DAO
    the approval must include the DAO-authorized signature.

(j) ADDITIONAL INFORMATION

    For more information about this AD,  contact Steven Dzierzynski, Avia-
    tion Safety Engineer FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY
    11590; telephone 516-228-7300; email 9-avs-nyaco-cos@faa.gov.

(k) 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 this AD specifies otherwise.

(i) Transport Canada AD CF-2024-35, dated October 16, 2024.

(ii) [Reserved]

(3) For Transport Canada material identified in this AD, contact Transport
    Canada, Transport Canada National Aircraft Certification 159 Cleopatra
    Drive, Nepean, Ontario K1A 0N5, Canada; telephone 888-663-3639;  email
    TC.AirworthinessDirectives-Consignesdenavigabilite.TC@tc.gc.ca;website
    tc.canada.ca/en/aviation.

(4) You may view this material at the FAA, Airworthiness Products Section,
    Operational Safety Branch,  2200 South 216th St.,  Des Moines, WA. For
    information on the availability of this material at the FAA, call 206-
    231-3195.

(5) You may view this material at the National Archives and Records Admin-
    istration (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, Com-
pliance & Airworthiness Division, Aircraft Certification Service.

FOR FURTHER INFORMATION CONTACT: Steven Dzierzynski, Aviation Safety Engi-
neer, FAA, 1600 Stewart Avenue, Suite 410,  Westbury, NY 11590;  telephone
516-228-7300; email 9-avs-nyaco-cos@faa.gov.