1947: Pilot Kenneth Arnold sights a series of unidentified flying objects near Washington’s Mt. Rainier. It’s the first widely reported UFO sighting in the United States, and, thanks to Arnold’s description of what he saw, leads the press to coin the term flying saucer.

Arnold was an experienced pilot with more than 9,000 hours of flying time. He had diverted from his flight plan — Chehalis to Yakima, Washington — to search for a Marine Corps C-46 transport plane reported down in the Cascades near the southwest slope of Mt. Rainier. A sweep of the area revealed nothing, and Arnold resumed his original course.

As Arnold recalled, the afternoon was crystal clear, and he was cruising at an altitude of 9,200 feet. A minute or two after noting a DC-4 about 15 miles behind and to the left of him, he was startled by something bright reflecting off his plane. At first he thought he had nearly hit another aircraft but as he looked off in the direction the light had come from, he saw nine “peculiar-looking” aircraft flying rapidly in formation toward Mt. Rainier.

As these strange, tailless craft flew between his plane and Mt. Rainier and then off toward distant Mt. Adams, Arnold noted their remarkable speed — he later calculated that they were moving at around 1,700 mph — and said he got a pretty good look at their black silhouettes outlined against Rainier’s snowy peak. He later described them as saucer-like disks … something the gentlemen of the press glommed on to very quickly.

At the time, Arnold said, the appearance of these flying saucers didn’t particularly alarm him, because he assumed they were some kind of experimental military aircraft. If they were, nobody in the War Department (soon to be merged into the Department of Defense) was saying.

In fact, the official Army Air Corps position was that Arnold had either seen a mirage or was hallucinating. He insisted he was perfectly alert and lucid, adding that he was not a publicity hound, either. He also invited both the Army and the FBI to investigate. The Army sent a couple of officers out to talk with Arnold. Even though they concluded that “a man of [his] character and apparent integrity” almost certainly saw what he claimed to have seen, the Army’s initial verdict remained unchanged.

As Arnold’s story leaked out, other people stepped forward to say they had seen the objects, too. The most-credible report may have come from a United Airlines crew, which reported seeing nine similar disk-like objects over Idaho only 10 days after Arnold’s sighting.

Whether Arnold actually saw something or not, the resulting publicity touched off a worldwide spate of UFO sightings. Barely two weeks after Arnold’s flight, the Roswell story broke, and UFO hysteria was on.

Was it the power of suggestion that led to all these sightings, or was 1947 a peak travel year for little green men? You decide.

Source: History.com, Project 1947

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