American Air Force planes take off in large numbers for a defence exercise.
Full title reads: "California. Aeroplanes by the hundred! Take part in quickly mobilised defence scheme to protest the Pacific Coast."
March Field, California, United States of America (USA).
Pan along air field with lots of war planes of the US Army Air Corps. ready for take off.
Aerial view of hundreds of planes on ground.
Planes start to take off.
Aerial and ground views of planes laying a smoke screen.