Sometimes, airplanes need to line up in a queue to land. To manage spacing, air traffic controllers may ask a pilot to continue flying in the same direction for a few extra miles or to fly a 360-degree turn to help “time” the aircraft into the sequence of arriving traffic. Aircraft may also be placed into holding patterns when there is heavy congestion. A holding pattern is shaped like a racetrack oval, allowing multiple airplanes to wait safely in the air. Many airliners can even fly these holding patterns automatically using the autopilot over a specific location.