Jack Gilbert “Jack” Graham was responsible for the worst mass murder in U.S. aviation history when, on November 1, 1955, he planted a dynamite time‑bomb in his mother’s suitcase aboard United Airlines Flight 629 departing Denver, Colorado. The explosion occurred over Lowe County farmland near Longmont around 7 p.m., instantly killing all 44 people aboard—39 passengers and 5 crew members—including his mother, Daisie King. Investigators quickly honed in on Graham, who had a criminal history of for