On the clear bright summer afternoon of 24 June 1947, pilot Kenneth Arnold was flying above the Cascades, a mountain range in Washington, USA, when he saw nine bat-wing shaped objects that “flew like a saucer would if you skipped it across the water”.

Advertisement

When he later tried to calculate their size and speed he was amazed to find they were moving at 1,200 miles per hour. This was double the speed of the most advanced jet aircraft at that time; it was not until October 1947 that test pilot Chuck Yeager first broke the sound barrier (760 mph at sea level).

Advertisement
Advertisement
Advertisement