What defines "Night" in Canada?

The term "Night" in Canada is defined as the time from evening civil twilight to morning civil twilight. This definition is crucial for pilots as it establishes the operational limitations and requirements that apply during nighttime flying.

Evening civil twilight occurs when the sun is between 0 and 6 degrees below the horizon, signaling the end of the day when there is still some light present. Morning civil twilight begins when the sun rises back above the horizon to the same degree. This definition helps determine the period during which pilots must adhere to specific regulations regarding visibility, equipment, and procedures tailored for nighttime operations, as opposed to the broader definition of night that might simply consider the hours between sunset and sunrise, which can often lead to ambiguity regarding operational readiness and regulations.

This precise delineation is critical for safe flying practices and compliance with aviation regulations pertaining to the night flying environment.