The U.S. Air Force admitted in 1952 that while most UFOs could be explained, others remained unidentified, including some “reports that have been made by credible observers of relatively incredible things.” This is one of those cases.
It happened just after noon on July 24, 1949, and involved a credible observer who was not seeking publicity. He reported a daylight encounter with a formation of unknown triangular aircraft demonstrating extraordinary maneuvers and performance. As they blew past his plane, electromagnetic interference affected his engine.
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| Piper Clipper, type of plane flown by the witness. |
The news was published in The Idaho Statesman, July 25, 1949, written by Dave Johnson, Aviation Editor. The lone witness spoke to authorities but insisted his name be kept out of the press.
Here's a slightly condensed version, from the paper’s evening edition:
Strange Flying Objects Leave Boise…
Investigation By Air Force To Be Started
Mysterious Craft Pass
Frightened Flyer
At Very Close RangeA Boise valley pilot told Sunday of seeing seven V-shaped flying objects at close range over the Mountain Home desert, and said the experience left him “frightened and shaken.”
The strange craft, he said, were not United States aircraft, as far as he could determine, and they had no visible means of propulsion, yet traveled at what he said was a “tremendous rate of speed.”
It has been learned that the Air Force's intelligence division is sending an operative to investigate the incident. The Boise valley pilot released the information only on the condition that his name not be used. He is the manager of one of the valley's major airports.
The pilot said the seven objects, or aircraft, came within 1000 or 2000 feet of his plane as he was flying toward Boise, about 10 miles west of Mountain Home.
No Pilot Discernible
They looked like a V, he said, with a circular body within the V and a belly-like object sitting under the nose of the V. He said that he could see no sign of a pilot or “anything like a human being” in the aircraft.
The color, he said, was not the metallic color one usually associates with military aircraft. He said it was “neither white nor gray” but a shade that he had never seen before.
A circular portion of the body just behind the nose of the V appeared to change in color from time to time, he said, and the outer edges of the V seemed to [oscillate] once or twice during the two minutes he had the craft under observation.
The pilot saw the objects at 12:05 p.m. yesterday while he was at an altitude of 10,000 feet on the right hand side of the highway from Mountain Home to Boise.
No Markings on Craft
He said the objects came up from his left side at about 9000 feet and crossed in front of his plane to the right, and disappeared on an easterly heading at “tremendous speed.”
There were no visible markings on the craft, he said. Their formation was unlike any ordinary military formation flying. He said they were in two “tight lines of three each, with the seventh object either in the middle of the lines or slightly above.”
He said he could not see a propeller or any smoke trail indicating jet or rocket power in the objects.
The pilot said the objects departed between the mountains and the town of Mountain Home. The Mountain Home air base, informed of the occurrence, said it had “no experimental aircraft on the field.”
And, the Air Force's flight center at McChord Field, Wash., said no formation of aircraft had been cleared through this area. The pilot said the experience left him with a “funny, ghostly feeling.”
The Associated Press and United Press news agencies picked up the story and it spread nationwide.
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| Associated Press story - Tyler Morning Telegraph, July 25, 1949 |
The Air Force File
At the time, Unidentified Aerial Objects were being investigated by the U.S. Air Force under Project Grudge, and they were on this case immediately. The information that follows is chiefly based upon the file held in the records of Project Blue Book and contains details far beyond what appeared in the press.
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| Clark’s sketches of the UFO made for the Air Force |
Harry Frank Clark leased the small Ritchey Field Airport from the city of Nampa, Idaho in 1939, serving as its manager. He also opened Clark’s Flying Service there with his wife Vivienne, the business including crop dusting and a flight school. During World War II, he was a commander in the local Civil Air Patrol, a flight instructor training pilots for the U.S. Army and Navy. (For further biographical details, see the 1940s entry from Who’s Who for Idaho.)
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| Harry Frank Clark (1899–1988) |
At the time of his sighting, Harry Clark was 49 years old, with 21 years of flying experience. He was flying his new Piper Clipper in a nearly cloudless sky, visibility excellent. Clark initially thought he was seeing F-51 Mustangs in an unusual formation until he got a closer look and saw the shape was all wrong. These objects had a and they had a larger wingspan than a Mustang and were flying at about twice its top speed. He assumed the objects were metal airframes, but their color was, “Darker than normal aluminum skin and not shiny. …seemed to be between a light gray and a dirty white with no markings…” They had no visible means of propulsion, no windows or portholes, and the flat triangles scarcely had room for a person or an engine as we know it.
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| F-51 Mustang compared to the UFO. |
The description of the UFOs from the Project Grudge interviews:
“…Clark said they were delta shaped flying wings. He estimated their span as being between that of an F-51 and an A-26 aircraft (35 to 55 feet), their length (nose to trailing edge) at about 20 to 30 feet, and their thickness at 2 to 5 feet. Clark said that the objects were a light color except for a circle of dark color of approximately 12 feet in diameter… and that the bottom of the object was flat except for a shallow dome-like protrusion of approximately 10-12 feet in diameter, with a depth of approximately 2 to 5 feet.”
The report by Lt. Col. Earl J. Liversay report described the maneuvers in the aerial encounter:
“Mr. Clark was enroute from Burley, Idaho, to Nampa, Idaho, in a Cub Cruiser when the objects were sighted. When the formation was first sighted they were going in approximately the same direction as Mr. Clark and were approximately one-fourth (1/4) of a mile to his left and below. Mr. Clark was cruising at ten (10) thousand feet at the time. He observed the formation until it made the one hundred and eighty (180) degree turn at which time Mr. Clark descended in his aircraft and made a ninety (90) degree turn to the left in an effort to intercept the formation. He was able to get below the level of the formation at eight (8) thousand five (5) hundred feet at which time he noticed the dark circular bulge on the bottom side of the objects. Because of their speed the flying objects soon became lost from the sight of Mr. Clark who proceeded on to his destination. Mr. Clark is known personally by Captain [redacted] of this organization who states that in his opinion Mr. Clark is a reliable witness.”
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| Simulated approximation of the UFO formation. |
When the objects made their 180-degree turn, Clark thought they were attacking his plane. The extraordinary maneuver was made in unison by the formation of objects, “without a bank or skid.” Clark originally observed the objects from above but as they changed course, got a good look at them from the front and in profile. As they flew past him, he expected great turbulence but there was nothing, not even a sound. However, his plane engine began running rough. The objects flew away from him at 600 mph or so, but they did not gradually fade from view as expected, they suddenly “disappeared from sight.”
After a few minutes’ thought, Clark made an emergency radio transmission to Gowen Field (Boise, Idaho) asking them to check for aircraft in the area. The results were negative, and a subsequent Air Force inquiry found no records of any military aircraft flying in the area.
Once he landed back at his airfield in Nampa, Clark had a mechanic inspect the engine. All eight of his spark plugs were found to have “been shorted and burned out,” and were discarded and replaced. When the Air Force investigator asked for them, only seven were found in the waste can. They were examined at the lab at Wright-Patterson AFB. “A test of the spark plugs from Clark’s plane failed to show any evidence of having broken down and were found to be entirely serviceable." The files provide no insight into the conflicting information.
Unidentified
The Air Force investigated into September, but were unable to locate any additional witnesses, or anything to either prove or disprove Clark’s report, eventually the case was closed as “Unidentified.”
Harry Clark did not seek fame as a UFO witness and as far as is known, his life was not disrupted by the sighting. He continued to operate his flying service until his retirement in 1975. He died Jan. 4, 1988, and was buried in Caldwell, Canyon, Idaho. No mention of the UFO sighting was made in his obituary, which can be found at the Find a Grave site.
