 Another well-documented specific comparison of the objects to saucers was the Kenneth Arnold sighting on June 24, 1947, while Arnold was flying near Mount Rainier.He reported seeing 9 brightly reflecting vehicles, one shaped like a crescent but the others more disc- or saucer-shaped, flying in an echelon formation, weaving like the tail of a kite, flipping and flashing in the sun, and traveling with a speed of at least 1,200 miles per hour (1,900 km/h).In addition to the saucer or disc shape (Arnold also used the terms "pie plate" and half-moon shaped), he also later said he described the motion of the craft as "like a saucer if you skip it across water", leading to the term "flying saucer" and also "flying disc" (which were synonymous for a number of years).