That kludge of a plane they used for the movie killed...
Hollywood's top stunt pilot, a man named Paul Mantz (search for his name in this list to see how many movies he was in). The plane was lashed together and lasted just long enough for that brief flight shown in the movie. When Mantz landed, the plane split in half right behind the cockpit then tumbled.
Mantz was a legend in the aviation community in a career that spanned decades. From everthing I've ever read about him, he was one hell of a guy and a terrific pilot.
A History of Hollywood’s Aerial Cinematography