2026-10382: Airworthiness Directives; Bombardier, Inc., Airplanes

Federal Register, Volume 91 Issue 100 (Tuesday, May 26, 2026) [Federal Register Volume 91, Number 100 (Tuesday, May 26, 2026)] [Proposed Rules] [Pages 30516-30519] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 2026-10382] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA-2026-4642; Project Identifier MCAI-2024-00705-T] RIN 2120-AA64 Airworthiness Directives; Bombardier, Inc., Airplanes

Agency

Federal Aviation Administration (FAA), DOT.

Action

Notice of proposed rulemaking (NPRM). -----------------------------------------------------------------------

Summary

The FAA proposes to adopt a new airworthiness directive (AD) for all Bombardier, Inc., Model CL-600-1A11 (600), CL-600-2A12 (601), and CL-600-2B16 (601-3A, 601-3R, and 604 Variants) airplanes. This proposed AD was prompted by an in-flight uncommanded, unarrested flaps movement accompanied by a FLAPS FAIL caution message. This proposed AD would require revising the existing aircraft flight manual (AFM) to provide the flightcrew with procedures to follow in the event of an uncommanded, unarrested flap movement. The FAA is proposing this AD to address the unsafe condition on these products.

Dates

The FAA must receive comments on this proposed AD by July 10, 2026.

Addresses

You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: Federal eRulemaking Portal: Go to regulations.gov. Follow the instructions for submitting comments. Fax: 202-493-2251. Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590. Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2026-4642; 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 NPRM, the mandatory continuing airworthiness information (MCAI), any comments received, and other information. The street address for Docket Operations is listed above. Material Incorporated by Reference: For Transport Canada material identified in this proposed AD, contact Transport Canada, Transport Canada National Aircraft Certification, 159 Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada; telephone 888-663-3639; email [email protected]. You may find this material on the Transport Canada website at tc.canada.ca/en/aviation. It is also [[Page 30517]] available at regulations.gov under Docket No. FAA-2026-4642. 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.

For Further Information Contact

Christopher Spencer, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: 516-228-7300; email: [email protected].

Supplementary Information

Comments Invited The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments using a method listed under the ADDRESSES section. Include ``Docket No. FAA-2026-4642; Project Identifier MCAI-2024-00705-T'' at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments. Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM. Confidential Business Information CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as ``PROPIN.'' The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Christopher Spencer, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: 516-228-7300; email: [email protected]. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking. Background Transport Canada, which is the aviation authority for Canada, has issued Transport Canada AD CF-2024-39, dated November 29, 2024 (Transport Canada AD CF-2024-39) (also referred to as the MCAI), to correct an unsafe condition for all Bombardier, Inc., Model CL-600-1A11 (600), CL-600-2A12 (601), and CL-600-2B16 (601-3A, 601-3R, and 604 Variants) airplanes. The MCAI states that a Model CL-600-2B16 airplane experienced an in-flight uncommanded, unarrested flaps movement from 0 to 45 degrees accompanied by a FLAPS FAIL caution message. The airplane returned to the departure airport without further incident. The flaps control system should have stopped the flaps at 3 degrees; however, a failed retract relay prevented the system from arresting the uncommanded movement. The uncommanded and unarrested flap movement, if not addressed, could result in loss of control of the airplane. The FAA is proposing this AD to address the unsafe condition on these products. You may examine the MCAI in the AD docket at regulations.gov under Docket No. FAA-2026-4642. Related Actions Transport Canada issued related Transport Canada AD CF-2023-07, dated February 10, 2023 (Transport Canada AD CF-2023-07), as an interim action to address the failure of the flap control system to arrest the uncommanded flap extension. The FAA issued AD 2023-17-06, Amendment 39- 22532 (88 FR 63004, September 14, 2023) (AD 2023-17-06), to address Transport Canada AD CF-2023-07. AD 2023-17-06 requires initial and repetitive operational tests of the flap control system. The FAA issued this AD as a standalone AD as the required actions are separate from each other. Material Incorporated by Reference Under 1 CFR Part 51 Transport Canada AD CF-2024-39 specifies procedures for revising the AFM to provide the flightcrew with procedures to follow in the event of an uncommanded, unarrested flap movement. 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. FAA's Determination These products have been approved by the civil aviation authority of another country and are approved for operation in the United States. Pursuant to the FAA's bilateral agreement with this State of Design Authority, that authority has notified the FAA of the unsafe condition described in the MCAI referenced above. The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop in other products of the same type design. Proposed AD Requirements in This NPRM This proposed AD would require accomplishing the actions specified in Transport Canada AD CF-2024-39 described previously, except for any differences identified as exceptions in the regulatory text of this proposed AD. Compliance With AFM Revisions Transport Canada AD CF-2024-39 requires operators to ``advise all flight crews'' of revisions to the AFM, and ``thereafter operate the aeroplane accordingly.'' However, this proposed AD would not specifically require those actions as those actions are already required by FAA regulations. FAA regulations require operators furnish to pilots any changes to the AFM (for example, 14 CFR 121.137), and to ensure the pilots are familiar with the AFM (for example, 14 CFR 91.505). As with any other flightcrew training requirement, training on the updated AFM content is tracked by the operators and recorded in each pilot's training record, which is available for the FAA to review. FAA regulations also require pilots to follow the procedures in the existing AFM including all updates. Explanation of Required Compliance Information In the FAA's ongoing efforts to improve the efficiency of the AD process, the FAA developed a process to use some civil aviation authority (CAA) ADs as the primary source of information for compliance with requirements for corresponding FAA ADs. The FAA has been coordinating this process with manufacturers and CAAs. As a result, the FAA proposes to incorporate Transport Canada AD CF-2024-39 by reference in the FAA final rule. This proposed AD would, therefore, require compliance with Transport Canada AD CF-2024-39 in its entirety through that incorporation, except for any differences identified as exceptions in the regulatory text of this proposed AD. Material required by Transport Canada AD CF-2024-39 for [[Page 30518]] compliance will be available at regulations.gov under Docket No. FAA- 2026-4642 after the FAA final rule is published. Costs of Compliance The FAA estimates that this AD, if adopted as proposed, would affect 610 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD: Estimated Costs for Required Actions ---------------------------------------------------------------------------------------------------------------- Cost per Cost on U.S. Labor cost Parts cost product operators ---------------------------------------------------------------------------------------------------------------- 1 work-hour x $85 per hour = $85............................. $0 $85 $51,850 ---------------------------------------------------------------------------------------------------------------- Authority for This Rulemaking Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII: Aviation Programs, describes in more detail the scope of the Agency's authority. The FAA is issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701: General requirements. Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. Regulatory Findings The FAA determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. For the reasons discussed above, I certify this proposed regulation: (1) Is not a ``significant regulatory action'' under Executive Order 12866, (2) Would not affect intrastate aviation in Alaska, and (3) Would not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. The Proposed Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows: PART 39--AIRWORTHINESS DIRECTIVES 0