The aircraft crashed 20 miles from the airport. ATC error in directing the plane in the wrong direction into mountainous terrain that was obscured by smoke and haze due to forest fires in the area. The source of ignition energy for the explosion could not be determined with certainty but, of the sources evaluated by the investigation, the most likely was a short circuit outside of the center wing tank that allowed excessive voltage to enter it through electrical wiring associated with the fuel quantity indication system. The crew reported smoke in the cockpit and requested an emergency landing at Halifax. The aircraft disappeared from radar and crashed into the Atlantic Ocean southwest of Halifax.
Preliminary indications are that a major fire erupted in the cockpit or avionics bay below.
Dr. Jonathan Mann, researcher in the fight against AIDS killed in the crash. The aircraft was on a flight from Seoul to Guam. The runway glide slope system was inoperative. The crew was informed the glide slope was inoperative and apparently was executing the localizer only approach procedure to the runway. The plane was possibly overloaded.