The document below is one of the collection of statements by people about Kenneth Arnold's June 24, 1947 sighting report . This is a part of the case file raw data. See the case file here.
As a Captain of the USAF, Edward J. Ruppelt was in charge of the Air Force investigation of UFO sighting reports, Project Bluebook, from early 1951 until September 1953. His book is one of the first that showed what the US military actually thinks about UFO sighting reports.
Source:
"The Report on Unidentified Flying Objects", book by Edward J. Ruppelt, USAF ret., Doubleday publishers, USA, 1956.
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The UFO story started soon after June 24, 1947, when newspapers all over the United States carried the first flying saucer report. The story told how nine very bright, disk shaped objects were seen by Kenneth Arnold, a Boise, Idaho, businessman, while he was flying his private plane near Mount Rainier, in the state of Washington. With journalistic license, reporters converted Arnold's description of the individual motion of each of the objects like "a saucer skipping across water"- into "flying saucer," a name for the objects themselves. In the eight years that have passed since Arnold's memorable sighting, the term has become so common that it is now in Webster's Dictionary and is known today in most languages in the world.
For a while after the Arnold sighting the term "flying saucer" was used to describe all disk shaped objects that were seen flashing through the sky at fantastic speeds. Before long, reports were made of objects other than disks, and these were also called flying saucers. Today the words are popularly applied to anything seen in the sky that cannot be identified as a common, everyday object.
Thus a flying saucer can be a formation of lights, a single light, a sphere, or any other shape; and it can be any color. Performance wise, flying saucers can hover, go fast or slow, go high or low, turn 90 degree corners, or disappear almost instantaneously.
Obviously the term "flying saucer" is misleading when applied to objects of every conceivable shape and performance. For this reason the military prefers the more general, if less colorful, name: unidentified flying objects. UFO (pronounced Yoo-foe) for short.
Officially the military uses the term "flying saucer" on only two occasions. First in an explanatory sense, as when briefing people who are unacquainted with the term "UFO": "UFO - you know - flying saucers." And second in a derogatory sense, for purposes of ridicule, as when it is observed, "He says he saw a flying saucer."
This second form of usage is the exclusive property of those persons who positively know that all UFO's are nonsense. Fortunately, for the sake of good manners if for no other reason, the ranks of this knowing category are constantly dwindling. One by one these people drop out, starting with the instant they see their first UFO.
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Although a formal Project for UFO investigation wasn't set up until September 1947, the Air Force had been vitally interested in UFO reports ever since June 24, 1947, the day Kenneth Arnold made the original UFO report.
As Arnold's story of what he saw that day has been handed down by the bards of saucerism, the true facts have been warped, twisted, and changed. Even some points in Arnold's own account of his sighting as published in his book, The Coming Of The Saucers, do not jibe with what the official files say he told the Air Force in 1947. Since this incident was the original UFO sighting, I used to get many inquiries about it from the Press and at briefings. To get the true and accurate story of what did happen to Kenneth Arnold on June 24, 1947, I had to go back through old newspaper files, official reports, and talk to people who had worked on Project Sign. By cross-checking these data and talking to people who had heard Arnold tell about his UFO sighting soon after it happened, I finally came up with what I believe is the accurate story.
Arnold had taken off from Chehalis, Washington, intending to fly to Yakima, Washington. About 3:00 P.M. he arrived in the vicinity of Mount Rainier. There was a Marine Corps C-46 transport plane lost in the Mount Rainier area, so Arnold decided to fly around awhile and look for it. He was looking down at the ground when suddenly he noticed a series of bright flashes off to his left. He looked for the source of the flashes and saw a string of nine very bright disk shaped objects, which he estimated to be 45 to 50 feet in length. They were travelling from north to south across the nose of his airplane. They were flying in a reversed echelon (i.e., lead object high with the rest stepped down), and as they flew along they weaved in and out between the mountain peaks, once passing behind one of the peaks. Each individual object had a skipping motion described by Arnold as a "saucer skipping across water."
During the time that the objects were in sight, Arnold had clocked their speed. He had marked his position and their position on the map and again noted the time. When he landed he sketched in the flight path that the objects had flown and computed their speed, almost 1,700 miles per hour. He estimated that they had been 20 to 25 miles away and had travelled 47 miles in 102 seconds.
I found that there was a lot of speculation on this report. Two factions at ATIC had joined up behind two lines of reasoning. One side said that Arnold had seen plain, everyday jet airplanes flying in formation. This side's argument was based on the physical limitations of the human eye, visual acuity, the eye's ability to see a small, distant object. Tests, they showed, had proved that a person with normal vision can't "see" an object that subtends an angle of less than 0.2 second of arc. For example, a basketball can't be seen at a distance of several miles but if you move the basketball closer and closer, at some point you will be able to see it. At this point the angle between the top and bottom of the ball and your eye will be about 0.2 of a second of arc. This was applied to Arnold's sighting. The "Arnold-saw-airplanes" faction maintained that since Arnold said that the objects were 45 to 50 feet long they would have had to be much closer than he had estimated or he couldn't even have seen them at all. Since they were much closer than he estimated, Arnold's timed speed was all wrong and instead of going 1,700 miles per hour the objects were travelling at a speed closer to 400 miles per hour, the speed of a jet. There was no reason to believe they weren't jets. The jets appeared to have a skipping motion because Arnold had looked at them through layers of warm and cold air, like heat waves coming from a hot pavement that cause an object to shimmer.
The other side didn't buy this idea at all. They based their argument on the fact that Arnold knew where the objects were when he timed them.
After all, he was an old mountain pilot and was as familiar with the area around the Cascade Mountains as he was with his own living room. To cinch this point the fact that the objects had passed behind a mountain peak was brought up. This positively established the distance the objects were from Arnold and confirmed his calculated 1,700-miles-per-hour speed. Besides, no airplane can weave in and out between mountain peaks in the short time that Arnold was watching them. The visual acuity factor only strengthened the "Arnold-saw-a-flying-saucer" faction's theory that what he'd seen was a spaceship. If he could see the objects 20 to 25 miles away, they must have been about 210 feet long instead of the poorly estimated 45 to 50 feet.
In 1947 this was a fantastic story, but now it is just another UFO report marked "Unknown." It is typical in that if the facts are accurate, if Arnold actually did see the UFO's go behind a mountain peak, and if he knew his exact position at the time, the UFO problem cannot be lightly sloughed off; but there are always "ifs" in UFO reports. This is the type of report that led Major General John A. Samford, Director of Intelligence for Headquarters, Air Force, to make the following comment during a Press conference in July 1952: "However, there have remained a percentage of this total [of all UFO reports received by the Air Force], about 20 per cent of the reports, that have come from credible observers of relatively incredible things. We keep on being concerned about them."
In warping, twisting, and changing the Arnold incident, the writers of saucer lore haven't been content to confine themselves to the incident itself; they have dragged in the crashed Marine Corps' C-46. They intimate that the same flying saucers that Arnold saw shot down the C-46, grabbed up the bodies of the passengers and crew, and now have them pickled at the University of Venus Medical School. As proof they apply the same illogical reasoning that they apply to most everything. The military never released photos of the bodies of the dead men, therefore there were no bodies. There were photographs and there were bodies. In consideration of the families of air crewmen and passengers, photos of air crashes showing dead bodies are never released.
Arnold himself seems to be the reason for a lot of the excitement that heralded flying saucers. Stories of odd incidents that occur in this world are continually being reported by newspapers, but never on the scale of the first UFO report. Occasional stories of the "Himalayan snowmen," or the "Malayan monsters," rate only a few inches or a column on the back pages of newspapers. Arnold's story, if it didn't make the headlines, at least made the front page. I had the reason for this explained to me one day when I was investigating a series of UFO reports in California in the spring of 1952.
I was making my headquarters at an air base where a fighter bomber wing was stationed. Through a mutual friend I met one of the fighter-bomber pilots who had known Arnold. In civilian life the pilot was a newspaper reporter and had worked on the original Arnold story. He told me that when the story first broke all the newspaper editors in the area were thoroughly convinced that the incident was a hoax, and that they intended to write the story as such. The more they dug into the facts, however, and into Arnold's reputation, the more it appeared that he was telling the truth. Besides having an unquestionable character, he was an excellent mountain pilot, and mountain pilots are a breed of men who know every nook and cranny of the mountains in their area. The most fantastic part of Arnold's story had been the 1,700-miles-per-hour speed computed from Arnold's timing the objects between two landmarks. "When Arnold told us how he computed the speed," my chance acquaintance told me, "we all put a lot of faith in his story." He went on to say that when the editors found out that they were wrong about the hoax, they did a complete about-face, and were very much impressed by the story. This enthusiasm spread, and since the Air Force so quickly denied ownership of the objects, all of the facts built up into a story so unique that papers all over the world gave it front-page space.
There was an old theory that maybe Arnold had seen wind whipping snow along the mountain ridges, so I asked about this. I got a flat "Impossible." My expert on the early Arnold era said, "I've lived in the Pacific Northwest many years and have flown in the area for hundreds of hours. It's impossible to get powder snow low in the mountains in June. Personally, I believe Arnold saw some kind of aircraft and they weren't from this earth." He went on to tell me about two other very similar sightings that had happened the day after Arnold saw the nine disks. He knew the people who made these sightings and said that they weren't the kind to go off "half cocked." He offered to get a T-6 and fly me up to Boise to talk to them since they had never made a report to the military, but I had to return to Dayton so I declined.
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The document below is one of the collection of statements by people about Kenneth Arnold's June 24, 1947 sighting report . This is a part of the case file raw data. See the case file here.