Trivia

Despite being portrayed as a villain, NASA provided technical assistance, including mock-up spacecraft, sets, vehicles, front screen projection expertise.

One of the stunt pilots, Frank Tallman, who flew the red stearman plane, claimed this film was the most dangerous film he'd ever flown for. He was killed in a crash soon after filming finished.

At the time of the picture's release, Hollywood aviation expert Frank Tallman said of the film's dogfight flying finale between a bi-plane and two helicopters: "It is the most dangerous and complex aerial sequence ever executed for a movie".

During his interview in the 2016 ESPN documentary O.J.: Made in America, Capricorn One director Peter Hyams admitted that the studio had given him a mandate to cast O.J. Simpson as John Walker. Hyams said, "I thought there were worthy African American actors who had paid their dues as actors, who had shown their talent. My first choice was either Robert Hooks or Bernie Casey, so my reaction was less than enthusiastic. I had seen The Towering Inferno (1974). I thought [Simpson's acting ability] was not going to frighten Daniel Day-Lewis. O. J. was a celebrity of enormous stature, and somebody who had not shown the chops to play the part. My goal was to see if I could make this guy work for what I wanted. It came time to do his last scene. He's a guy who's parched and delusional. So rather than him acting somebody who was desperately thirsty, I put appliances on his face that made it difficult for him to move and difficult to talk, and it just made him sound like he was in desperate trouble. And he was pretty good. You know, what can I say? He was a charming, terrific guy, he was a positive guy, he tried very hard, and it was clear that he saw a future for himself in film."

The most successful independently produced picture at the box-office for the year of 1977.