Watch "The Court-Martial of Billy Mitchell" on YouTube
Jack felt a special affection for The Court-Martial of Billy Mitchell (1955), in which he appeared alongside Gary Cooper. He had met Coop several years earlier, in New York, while selling Cadillacs. Coop entered the showroom to see a Duesenberg, which some sources say he once owned. In any case, Coop took Jack to lunch, and they struck up a friendship that lasted until Coop's death in 1961. Jack said Coop was a role model for him as he learned the craft of acting. The two appeared again in Man of the West (1958) in which their characters engaged in a free-for-all over, you guessed it, a woman!
Jack portrayed Navy LCDR Zachary Lansdowne, who was killed when his airship, Shenandoah, crashed over Ohio in a storm. In those early days of military aviation (1920s through 1940s), not everyone thought aircraft were either safe or effective. LCDR Lansdowne's death affected COL Mitchell deeply and influenced his strong stand for aviation safety, even though his stand subjected him to court-martial and cost him his rank.
Today, Billy Mitchell is a hero among military aviators.