Flight Controls — Uncommanded and Unarrested Flap Movement
- Published
- Effective
- Replaces
- 2023-07
- Replaces
- 2025-51
AI-generated summary of the official EASA document. Verify against the PDF before acting.
What to do
Operators must perform functional tests of flap extension and retraction within specified intervals and adhere to the new life limits for flap relays as detailed in the applicable Bombardier TLMC manuals and Temporary Revisions dated February 25, 2025. Compliance with these tasks is mandatory unless already accomplished. The directive became effective on December 12, 2025.
Summary
Canadian Airworthiness Directive CF-2025-51R1 addresses uncommanded and unarrested flap movement issues on Bombardier Inc. CL-600-1A11, CL-600-2A12, and CL-600-2B16 aircraft models. This directive mandates functional tests and introduces life limits for flap extension and retraction relays to prevent flap control failures. It aims to enhance flight safety by mitigating risks of flap malfunctions that could lead to loss of aircraft control.
What changed
CF-2025-51R1 revises the compliance statement and maintains the requirements of the previous AD CF-2025-51. It supersedes AD CF-2023-07 and updates the maintenance tasks by incorporating new limitations in the Airworthiness Limitation section of Bombardier Time Limits/Maintenance Checks manuals. The directive also references updated Temporary Revisions applicable to various CL-600 series models.
Why it matters
This directive is critical for operators and maintenance organizations to prevent uncommanded flap movements that could compromise flight safety. Compliance ensures early detection and correction of relay failures that may otherwise go unnoticed, reducing the risk of in-flight flap malfunctions. It supports regulatory compliance and helps maintain aircraft airworthiness standards.
More for Bombardier CL-600 (Challenger)
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