What does it mean when a flight is holding?

When a flight is holding, it means that the aircraft is maintaining a specific altitude and speed while flying in a predetermined pattern. This procedure is typically implemented when the aircraft cannot land immediately due to traffic congestion, poor weather conditions, or other operational delays at the airport. The holding pattern allows the flight to wait safely in a designated airspace until it is cleared for landing or given further instructions.

In this context, the other choices either describe actions that do not align with holding or imply different operational situations. For example, preparing for landing indicates that the aircraft is actively descending, which is not compatible with holding. A state of emergency suggests urgent circumstances that require immediate attention, and completing its route implies the flight has reached its destination, neither of which pertain to the ongoing holding procedure that involves circling or flying in a specified area.