On October 25, 1999, a chartered Learjet 35 was scheduled to fly from Orlando, Florida, to Dallas, Texas. Early in the flight, the aircraft, which was cruising at altitude on autopilot, quickly lost cabin pressure and all on board were incapacitated due to hypoxia — a lack of oxygen. The aircraft failed to make the westward turn toward Dallas over north Florida and continued on its northwestern course, flying over the southern and midwestern United States for almost four hours and 1,500 miles (2,400 km). The plane ran out of fuel over South Dakota and crashed into a field near Aberdeen after an uncontrolled descent.