Kenneth Arnold — First Modern UAP Sighting Mount Rainier 1947

On June 24, 1947, experienced private pilot and businessman Kenneth Arnold was flying his single-engine CallAir A-2 on a search mission near Mount Rainier, Washington, when he observed nine bright, crescent-shaped objects flying in a chain formation at high speed between Mount Rainier and Mount Adams. Arnold timed the objects between two peaks and calculated their speed at approximately 1700 mph — nearly three times the maximum speed of any known aircraft of the era. He described the objects as flying in a weaving motion, 'like the tail of a kite' or 'like a saucer skipped across water.' He estimated them to be about 45 to 50 feet long. Arnold landed at Yakima and reported the sighting to the airport authority, then filed a full report with the FBI and Army Air Force. A wire service reporter's paraphrase of Arnold's description — 'flying saucers' — entered the global lexicon immediately. Within weeks, thousands of similar sightings were reported worldwide. The USAAF took the Arnold report seriously enough to initiate Project Sign, the first official US UAP investigation program. Arnold's aeronautical credentials, his timing methodology, and his willingness to go on record made his report the anchor event of modern UFO history. He was never shaken from his account and maintained consistency throughout his life.