What happened
Flying his small CallAir plane from Chehalis toward Yakima, Idaho businessman Kenneth Arnold broke off a search for a missing Marine transport when a sharp flash caught his eye. Off to the north of Mount Rainier he counted nine bright, thin objects strung out in a stepped chain, flipping and glinting as they weaved past the peaks. He saw no tails or wings in the usual sense. Timing them between Rainier and Mount Adams on his panel clock, he worked out a speed far beyond any aircraft of 1947, then rounded it down to about 1,200 mph to be safe. Landing in Pendleton the next day, he told reporters at the East Oregonian, and within 48 hours headline writers across the country had coined the phrases 'flying saucer' and 'flying disc'. Hundreds of similar reports followed that summer. Army Air Forces intelligence interviewed him in July, and his account became the opening case of the modern UFO era.
The official explanation
The Army Air Forces publicly concluded Arnold had seen a mirage. Officials at McChord Field and White Sands suggested jet aircraft such as P-80s, though none were known to be in the area. Harvard astronomer Donald Menzel offered, over the years, blowing snow, mountain wave clouds and water drops on the windshield. Steuart Campbell proposed mirages of distant snowy peaks; Philip Klass pointed to meteors; James Easton and others suggested a line of large American white pelicans catching the sun.
The anomalous case
Arnold was an experienced mountain pilot, and the two Army Air Forces intelligence officers who interviewed him in July 1947 wrote that they believed he actually saw what he described. He ran simple checks in the air, rocking his plane and lowering his window, to rule out reflections on glass. His timing between two fixed landmarks gave a speed well above anything flying in 1947, and an AAF analysis estimated the objects at 140 to 280 feet long. A fire lookout south of Yakima reported flashes over Rainier at the same hour. Ruppelt wrote that Air Force investigators called the blowing-snow theory flatly impossible, and Project Sign staff split over whether jets could explain it. Most importantly, the AAF's own secret review that summer, which included Arnold's case, concluded the saucers were something real, and led directly to the Twining memo and Project Sign.
The strongest argument that this was something genuinely unknown or classified, with each claim attributed to the person who made it.
Documents
- Project BLUE BOOK records (National Archives, microfilm T-1206) official, archives.gov
Sources
- Kenneth Arnold UFO sighting Wikipedia
- Flying Saucers in Washington (Walt Crowley, HistoryLink Essay 2067) HistoryLink.org
- CIA's Role in the Study of UFOs, 1947-90 (Gerald K. Haines, Studies in Intelligence, 1997) Federation of American Scientists (reprint of CIA article)
Witness reports elsewhere
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