- Named Mainline Denver
- November 1,1955
- 6:52 pm
- Flight 629 took off from Denver, Colorado headed for Portland, Oregon
- In air for 11 minutes before crashing near Longmont, Colorado
- All 44 people on board were killed
- The accident spread evidence across 6 square miles in Weld County, Colorado
- Jack smuggled a dynamite bomb into his mother's luggage as a going away gift
- His aim was to kill his mother in order to collect her life insurance money
- Jack Gilbert had an extensive criminal history before the event
- The investigation was led by FBI director J. Edgar Hoover and Special Agent John McCulloch
- He was sentenced and put to death by gas chamber at the Colorado State Penitentiary
- Jack confessed he was inspired by the Albert Guay Affair in Quebec in 1949