On 4 September 2000, a chartered Beechcraft 200 Super King Air departed Perth for a flight to the mining town of Leonora, Western Australia. The aircraft crashed near Burketown, Queensland, Australia, resulting in the deaths of all eight occupants. During the flight, the aircraft climbed above its assigned altitude. When air traffic control (ATC) contacted the pilot, the pilot's speech had become significantly impaired, and he was unable to respond to instructions. Three aircraft intercepted the Beechcraft, but were unable to make radio contact. The aircraft continued flying on a straight north-easterly heading for five hours, before exhausting its fuel and crashing 40 mi (65 km) south-east of Burketown. The crash became known in the media as the "ghost flight".

On October 25, 1999, a chartered Learjet 35 business jet was scheduled to fly from Orlando, Florida, United States to Dallas, Texas, United States. Early in the flight, the aircraft, which was climbing to its assigned altitude on autopilot, lost cabin pressure, and all six on board were incapacitated by hypoxia, a lack of oxygen in the brain and body. The aircraft continued climbing past its assigned altitude, then 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, killing all six on board.