If a pilot loses visual reference while circling to land and ATC radar service is not available, what should be the missed approach action?

When a pilot loses visual reference while circling to land and is without ATC radar service, the appropriate missed approach action is to make a climbing turn toward the landing runway. This action is critical for safety and ensures that the aircraft remains in a positive climb while maneuvering.

By turning toward the landing runway, the pilot maintains a path that ideally will allow for reestablishing visual contact with the runway and provides a safer trajectory in case immediate action is needed, such as navigating around obstacles and minimizing the risk of entering a stall or losing further control of the aircraft. Additionally, it helps to conform to the standard missed approach procedures that prioritize returning to a flight path aligned with the runway.

In contrast, other options might lead to increased hazards. For example, proceeding straight ahead could place the aircraft further from the runway without a clear path back, while descending without visual contact may exacerbate the situation by risking a collision with terrain or obstacles. Making a climbing turn away from the departure runway is also not ideal, as it does not bring the aircraft closer to the desired safety and recovery path.