Do You Need a Departure Alternate? Let's Find Out

Do you know when a departure alternate is required?

Based on the weather forecast, when should you consider having a departure alternate?

Answer:

A departure alternate is required if the weather forecast for the departure aerodrome falls below the landing minimums for the lowest suitable approach. In addition, if the aerodrome is not expected to meet the approach and landing minimums 1 hour before to 1 hour after the estimated time of departure (totaling 120 minutes), a departure alternate is needed.

When planning for a flight, it is essential to consider when a departure alternate is required. A departure alternate is necessary if the weather forecast at the departure aerodrome indicates conditions that fall below the landing minimums for the lowest suitable approach. This means that if the visibility and cloud base are not sufficient for a safe landing, a departure alternate airport must be designated.

Moreover, the 120-minute rule plays a crucial role. If the aerodrome is not expected to meet the approach and landing minimums from 1 hour before to 1 hour after the planned departure time, a departure alternate is mandatory. This rule ensures that there is a backup option in case the aircraft cannot return to the departure aerodrome due to unforeseen circumstances, such as sudden weather changes.

Understanding the requirements for a departure alternate is essential for flight safety and proper planning. By following these guidelines, pilots can ensure a smooth and secure journey for themselves and their passengers.