No Highway in the Sky (1951)

Theodore Honey, portrayed by James Stewart, is an eccentric aeronautical engineer whose brilliance is overshadowed by his absent-mindedness. His research uncovers a dangerous flaw in a new aircraft model, which only becomes lethal after a specific number of flight hours. As he races to a crash site to validate his findings, Honey finds himself on a flight that is alarmingly close to reaching that critical threshold. With time running out, he must convince the crew and passengers of the impending danger before it's too late.