United Airlines Flight 629
United Airlines Flight 629 was a flight that flew from Stapleton Airport in Denver, Colorado to Portland, Oregon. This flight was bombed on November 1, 1955, killing all 44 people on board.The captain on the flight on that day, Lee Hall, was a World War II veteran.
The aircraft used was N37559, a Douglas DC-6B. The flight took off at 6:29 p.m. Denver time. Several sticks of dynamite planted on the aircraft exploded nine minutes later, at 6:38 p.m., while the flight was over Longmont, Colorado.
A man named Jack Gilbert Graham had planted this bomb to collect his mother's insurance money. The death penalty was administered on him a year later.
This incident remains the only incident of an airliner being destroyed by a bomb over the mainland United States.