Japan Airlines Flight 123 was a scheduled domestic Japan Airlines passenger flight from Tokyo's Haneda Airport to Osaka International Airport, Japan. On August 12, 1985, a Boeing 747SR operating this route suffered a sudden decompression twelve minutes into the flight and crashed in the area of Mount Takamagahara, Ueno, Gunma Prefecture, from Tokyo thirty-two minutes later. The crash site was on Osutaka Ridge, near Mount Osutaka.