The film is based on the Eagle Squadrons, American pilots who volunteered to fly for the Royal Air Force during World War II.

International Squadron featured noted Hollywood pilot Paul Mantz who acted as the film's aerial coordinator and flew during the production.

Faced with a breach-of-promise suit, Jimmy, however, is hired to deliver a new American-designed Lockheed Hudson bomber to the RAF, flying to England with his mechanic, "Omaha" McGrath (Cliff Edwards).

When they encounter a heavy fog over the English base, Jimmy ignores a request from Charles to bail out, and brings the bomber in to a safe landing.

When Jeanette's boyfriend, Michele Edmé (Tod Andrews) is selected for a dangerous bombing mission over Nazi-held territory, Jimmy knocks him out and takes his place.

Producer Darryl F. Zanuck of 20th Century Fox wrote angry letters to Hal Wallis of Warner Bros. accusing them of not only stealing his idea of his A Yank in the R.A.F.

The unlikely group included a Mantz's Boeing Model 100, Brown B-3 Racer, three Ryan STA trainers and a Travel Air Type R Mystery Ship.

[7] International Squadron was favorably reviewed by Theodore Strauss for The New York Times, who said: "As another aerial and romantic dog-fight in the hurtling succession of epics about the Royal Air Force, it breezes along with dash and bravado and not too much self-importance.