FAA Supersedes AD 2025-22-02: H-Stab Anti-Yaw Steady Fitting Block Bolt Checks and Replacement Required for Regional Jet Fleet

Rule

You may be interested in this older document that published on 01/27/2026 with action 'Notice of proposed rulemaking (NPRM).' View Document

Airworthiness Directives; MHI RJ Aviation ULC (Type Certificate Previously Held by Bombardier, Inc.) Airplanes

A Rule by the Federal Aviation Administration on 04/21/2026

• PDF

• Document Details

• Document Dates

• Table of Contents

- Related Documents

• Public Comments
• Regulations.gov Data

- Sharing

• Print
• Other Formats
• Public Inspection Published Document: 2026-07736 (91 FR 21245) Document Headings ###### Department of Transportation

Federal Aviation Administration

1. 14 CFR Part 39
2. [Docket No. FAA-2026-0728; Project Identifier MCAI-2025-01823-T; Amendment 39-23310; AD 2026-08-02]
3. RIN 2120-AA64 ( printed page 21245) # AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA is superseding Airworthiness Directive (AD) 2025-22-02, which applied to certain MHI RJ Aviation ULC (type certificate previously 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. AD 2025-22-02 required repetitive torque checks of the horizontal stabilizer (H-stab) anti-yaw steady fitting block bolts. Since the FAA issued AD 2025-22-02, it was determined that additional actions must be done to address the unsafe condition. This AD continues to require the actions in AD 2025-22-02 and requires replacing the H-stab anti-yaw steady fitting block hardware. The FAA is issuing this AD to address the unsafe condition on these products.

DATES:

This AD is effective May 26, 2026.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of November 20, 2025 (90 FR 49251, November 5, 2025).

ADDRESSES:

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2026-0728; 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, the mandatory continuing airworthiness information (MCAI), 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 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. You may find this material on the Transport Canada website at tc.canada.ca/en/aviation.
• 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. It is also available at regulations.gov under Docket No. FAA-2026-0728.

FOR FURTHER INFORMATION CONTACT:

Fatin Saumik, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: 516-228-7300; email: 9-avs-nyaco-cos@faa.gov.

SUPPLEMENTARY INFORMATION:

Background

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2025-22-02, Amendment 39-23180 (90 FR 49251, November 5, 2025) (AD 2025-22-02). AD 2025-22-02 applied to certain MHI RJ Aviation ULC (type certificate previously 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. AD 2025-22-02 required repetitive torque checks of the H-stab anti-yaw steady fitting block bolts. The FAA issued AD 2025-22-02 to address loose or missing bolts on the anti-yaw steady fitting block, which, when combined with a bird strike or gust loading, may result in loss of the H-stab and consequent loss of control of the airplane.

The NPRM was published in the Federal Register on January 27, 2026 (91 FR 3394). The NPRM was prompted by AD CF-2025-38, dated August 19, 2025 (Transport Canada AD CF-2025-38) (also referred to as the MCAI), issued by Transport Canada, which is the aviation authority for Canada. The MCAI states that loose or missing bolts on the anti-yaw steady fitting block, when combined with a bird strike or gust loading, may result in loss of the H-stab.

The preamble to AD 2025-22-02 specifies that the FAA considers that AD to be an “interim action” and that the FAA might consider further rulemaking to mandate the replacement of the H-stab anti-yaw steady fitting block hardware. The FAA has determined that this replacement must be required.

In the NPRM, the FAA proposed to continue to require the actions in AD 2025-22-02 and require replacing the H-stab anti-yaw steady fitting block hardware, as specified in Transport Canada AD CF-2025-38. The FAA is issuing 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-2026-0728.

Discussion of Final Airworthiness Directive

Comments

The FAA received a comment from the Air Line Pilots Association, International (ALPA) who supported the NPRM without change.

Conclusion

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 reviewed the relevant data, considered any comments received, and determined that air safety requires adopting this AD as proposed. Accordingly, the FAA is issuing this AD to address the unsafe condition on these products. Except for minor editorial changes, this AD is ( printed page 21246) adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator.

Material Incorporated by Reference Under 1 CFR Part 51

This AD requires Transport Canada AD CF-2025-38, dated August 19, 2025, which the Director of the Federal Register approved for incorporation by reference as of November 20, 2025 (90 FR 49251, November 5, 2025).

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.

Costs of Compliance

The FAA estimates that this AD affects 597 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD:

| Action | Labor cost | Parts cost | Cost per
product | Cost
on U.S.
operators |
| --- | --- | --- | --- | --- |
| Retained actions from AD 2025-22-02 | Up to 6 work-hours × $85 per hour = $510 | $0 | Up to $510 | Up to $304,470. |
| New actions | 7 work-hours × $85 per hour = $595 | 27 | $622 | $371,334. |
The FAA estimates the following costs to do any necessary on-condition action that would be required based on the results of any required actions. The FAA has no way of determining the number of aircraft that might need this on-condition action:

Labor cost	Parts cost	Cost per product
1 work-hour × $85 per hour = $85	Up to $28	Up to $113.

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

This AD will not have federalism implications under Executive Order 13132. This AD will 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 that this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866,

(2) Will not affect intrastate aviation in Alaska, and

(3) Will 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 Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39—AIRWORTHINESS DIRECTIVES

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) 2025-22-02, Amendment 39-23180 (90 FR 49251, November 5, 2025); and

b. Adding the following new AD:

2026-08-02 MHI RJ Aviation ULC (Type Certificate Previously Held by Bombardier, Inc.): Amendment 39-23310; Docket No. FAA-2026-0728; Project Identifier MCAI-2025-01823-T.

(a) Effective Date

This airworthiness directive (AD) is effective May 26, 2026.

(b) Affected ADs

This AD replaces AD 2025-22-02, Amendment 39-23180 (90 FR 49251, November 5, 2025) (AD 2025-22-02).

(c) Applicability

This AD applies to MHI RJ Aviation ULC (Type Certificate Previously 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, as identified in Transport Canada AD CF-2025-38, effective August 19, 2025 (Transport Canada AD CF-2025-38).

(d) Subject

Air Transport Association (ATA) of America Code 55, Stabilizers.

(e) Unsafe Condition

This AD was prompted by reports of loose and missing bolts on the horizontal stabilizer anti-yaw steady fitting block. The FAA is issuing this AD to address loose or missing bolts on the anti-yaw steady fitting block, which, when combined with a bird strike or gust loading, may result in loss of the horizontal stabilizer and consequent loss of control of the airplane.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done. ( printed page 21247)

(g) Requirements

Except as specified in paragraph (h) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, Transport Canada AD CF-2025-38.

(h) Exception to Transport Canada AD CF-2025-38

(1) Where Transport Canada AD CF-2025-38 refers to its effective date, this AD requires using November 20, 2025 (the effective date of AD 2025-22-02).

(2) Where Transport Canada AD CF-2025-38 refers to hours air time, this AD requires using flight hours.

(3) Where Transport Canada AD CF-2025-38 refers to the effective date of Transport Canada AD CF-2024-24 (July 4, 2024), this AD requires using the effective date of this AD.

(4) Where paragraph B. of Transport Canada AD CF-2025-38 specifies to repeat the torque check “every 2200 hours air time from the previous inspection”, for this AD, replace that text with “at intervals not to exceed 2,200 flight hours”.

(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 information 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 accomplished using a method approved by the Manager, International Validation Branch, FAA; or Transport Canada; or MHI RJ Aviation ULC's Transport 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 Fatin Saumik, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: 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 (IBR) 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.

(3) The following material was approved for IBR on November 20, 2025 (90 FR 49251, November 5, 2025).

(i) Transport Canada AD CF-2025-38, effective August 19, 2025.

(ii) [Reserved]

(4) 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. You may find this material on the Transport Canada website at tc.canada.ca/en/aviation.

(5) 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.

(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 16, 2026.

Steven W. Thompson,

Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.

[FR Doc. 2026-07736 Filed 4-20-26; 8:45 am]

BILLING CODE 4910-13-P

Published Document: 2026-07736 (91 FR 21245)