JA-8031 was engaged on a regular public transport flight from Sydney, Australia, to Manila, Philippines, thence to Tokyo, Japan, and was designated Japan Airlines Flight 772.
The aircraft had arrived at Sydney from Manila at 2200 hours Eastern Standard Time (EST) on 21st February and, after maintenance and routine servicing, engines were ground tested in an area set aside for this purpose. This work was completed at 0945 hours on 22nd February and the aircraft then remained unattended until 1120 hours on 22nd February when it was moved to the apron for pre-departure servicing and loading. After taxing at 1240 hours, the aircraft commenced to take off on Runway 34 at 1251 hours and, about one minute later, when the aircraft was at about 200 feet altitude, a person was seen to fall from the left main landing gear bay.