On November 1 , 1955 United Airlines Flight 629 , flying from Stapleton Airport in Denver to Portland , Oregon , was bombed , killing all 39 passengers and five crew members on board the Douglas DC-6B . The bomb was planted by Jack Graham who put the device in his mother 's luggage to collect on her life insurance policy . Graham was arrested , tried , and was executed a year after the explosion
United Airlines Flight 629
United Airlines Flight 629
History of United Airlines