Aeroplane flying by radio location finding - early radar?
Titles read: "PLANE SAFETY!"
Various locations of events.
Several brief shots of boats on rough sea, a wrecked ship in a storm, a crashed plane. Commentator talks of navigators piloting their craft without any outside aid, at the mercy of the elements. Brief shot of a blind man walking along a pavement with a white stick, as commentator says that radio direction-finding helps to find a way for unseeing eyes.
An aeroplane takes off from Le Bourget for Amsterdam. On board we see the navigator tapping out signals by morse code and the messages being received at ground control. The pilot flies into low-lying clouds and taps out a message to ask where he is. Various shots of men listening on radio sets and marking positions on large maps and eventually giving the position over the radio to the pilot. Several shots of aeroplanes flying, superimposed over a spinning globe to represent aircraft flying about the world.
Could be viewed as an early radar system.