Circle-to-land is a maneuver initiated by the pilot to align the aircraft with a runway for landing when a straight-in landing from an instrument approach is not possible or is not desirable, and only after ATC authorization has been obtained and the pilot has established and maintains required visual reference to the airport. A circle-to-land maneuver is an alternative to a straight-in landing. It is a maneuver used when a runway is not aligned within 30 degrees of the final approach course of the instrument approach procedure or the final approach requires 400 feet (or more) of descent per nautical mile, and therefore requires some visual maneuvering of the aircraft in the vicinity of the airport after the instrument portion of the approach is completed to align the aircraft with the runway for landing.