On November 15, 1979, the Boeing 727 serving the flight was attacked by Ted Kaczynski (also known as the Unabomber), who sent a pipe bomb in the mail and set it to detonate at a certain altitude.

The bomb partially detonated in the cargo hold and caused "a sucking explosion and a loss of pressure," which was then followed by large quantities of smoke filling the passenger cabin, forcing the pilots to make an emergency landing at Dulles International Airport.

[1][2][3] Twelve passengers had to be treated afterward for smoke inhalation.

[2] Bombing a commercial airliner, especially one flying through an interstate route as Flight 444 was at the time, and still is, a federal criminal offense.

This prompted federal authorities to assign the name "Unabomber" (for University and Airline Bomber) to the then-unknown suspect, and sparked one of the longest and most expensive manhunts in FBI history, which ended 17 years later with Kaczynski being arrested and charged in 1996.