A jet transporting military personnel vanishes over the Pacific Ocean in the early days of the Vietnam War

On March 16, 1962, Flight 739 was charted by the U.S. military to transport Army personnel and South Vietnamese from Travis Airforce Base in California to South Vietnam. The Super Constellation propeller jet had 96 passengers and a crew of 11.

After refueling in Guam, the plane headed for the Clark Air Force Base in the Philippines, but never made it. It went down somewhere in the Western Pacific. No wreckage or bodies were ever recovered. An hour after Flight 739's last radio communication, a Standard Oil tanker reported an explosion in the sky.

Was it a sabotage? A missile? Engine problems? No one knows, but the Civil Aeronautics Board concluded in its accident report “It can be reasonably assumed” that whatever befell Flight 739, “happened suddenly and without warning."