Navigation — 5G C-Band wireless Broadband Interference with Radio Altimeter System when operating in Canadian airspace
- Published
- Effective
AI-generated summary of the official EASA document. Verify against the PDF before acting.
What to do
Operators of DHC-8-401 and DHC-8-402 aircraft must comply with the directive within 53 days of November 19, 2025, by applying operational limitations in the aircraft flight manual supplements and installing required placards. They must also prohibit dispatch of aircraft with certain MEL items related to the anti-skid system. Finally, affected aircraft must be modified with approved service bulletins to install tolerant radio altimeters to lift interim restrictions.
Summary
The Canadian Airworthiness Directive CF-2025-55 addresses interference caused by 5G C-Band wireless broadband signals with radio altimeter systems on De Havilland Aircraft of Canada DHC-8-401 and DHC-8-402 aircraft operating in Canadian airspace. It mandates specific operational limitations and modifications to ensure safe aircraft operation amid 5G deployment. The directive focuses on mitigating risks associated with erroneous radio altimeter data due to 5G signal interference.
What changed
CF-2025-55 introduces new operational restrictions and corrective measures for DHC-8-401 and DHC-8-402 aircraft equipped with non-tolerant radio altimeters to mitigate 5G C-Band interference. It requires increased landing distance calculations, prohibits certain landing configurations, mandates cockpit placards, and restricts use of specific minimal equipment list items. The directive also requires aircraft modifications to install tolerant radio altimeters within 53 days of its effective date.
Why it matters
This directive is critical for aviation professionals as 5G C-Band interference can cause inaccurate radio altimeter readings, potentially compromising flight safety during critical phases like landing. Operators and maintenance teams must ensure compliance to avoid operational disruptions and maintain regulatory adherence. Understanding and implementing these measures protects aircraft systems and ensures continued safe operations in Canadian airspace.
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