Pilots, three in number, handle US Mail deliveries, battling all kinds of weather as they attempt to maintain postal service across a country where conditions can shift unexpectedly. “Jake,” portrayed by Pat O’Brien, is at the head of the group; Stuart Erwin plays “Tex,” who's reliable and steady; and James Cagney embodies “Dizzy,” a somewhat unpredictable character. This last fellow frequently creates difficulties f…