The television that the terrorist (Paul Smith) was using to monitor the news broadcast in the locomotive, was a Sharp Sidekick, Model 3T-50B made in 1978. This television was only available in black and white. The picture displayed on the unit in the film, however, was a color image.
In his 2022 book "Boldly Go", William Shatner recounts the filming of the scene in which his character runs across the top of the engine compartment. First a stuntman did the shot, with the train running about forty miles per hour. When director Richard C. Sarafian told Shatner they would probably be filming his close-up using background projection, Shatner proposed to go onto the moving train himself. The sequence was filmed at ten miles per hour, then at twenty miles but he still ended up performing the stunt at forty miles per hour because Sarafian felt that was the only way it would look authentic.