Set just before the outbreak of WWII, this is the story of a test pilot who works for the (unnamed) enemy. Made in 1939, by the time it was released in 1940, war had been declared.
Barry K. Barnes
Peter Thurloe
Joan Marion
Dorothy Houghton
Roger Livesey
Charles Houghton
Basil Radford
Bill Madison
Everley Gregg
Emily Madison
Felix Aylmer
Col. Cairns
Wallace Douglas
Agent Hooper
Henry Oscar
Porter
John Turnbull
Sir Andrew Hamilton
Edward Ashley
Stuart
Santos Casani
Foreigner
Hal Walters
Kingswell
David Davies
Detective (uncredited)
The Right Stuff
Little Nemo: Adventures in Slumberland Pilot 2
Test Pilot
The Man in the Sky
Q Planes
Tobor the Great
Jet Job
X-15
First Man into Space
Devil's Squadron
The McConnell Story
Wings of the Navy
Flight Lieutenant
Men Against the Sky
Emergency Landing
Power Dive
Beyond the Time Barrier
First Man
Toward the Unknown
People of Earth and Sky
The Great Waldo Pepper
Firefox
Love Is in the Air
Shadow in the Cloud
Flyboys
Hornblower: The Examination for Lieutenant
The Rocketeer
Die Alone
Interceptor
Sunday in New York
Hounds of War
Accident Man
The First of the Few
Monsters of Man
Sniper: The Last Stand
King of Killers
Suicide Squad
The Engineer
Icefall