Hill AFB, UtahMay 1949

On May 25, 1949, military personnel at Hill Air Force Base in Utah spotted two mysterious flying objects in the sky. The first sighting happened at 1405 hours (2:05 p.m.) when a first lieutenant and a salvage officer noticed an object flying dull silver in color at about nine to ten thousand feet. It appeared to be moving roughly forty miles per hour faster than an F-51 fighter plane traveling nearby. Moments later, they saw a second object, this one globular in shape and dark blue on one side with silver on the other, also heading southeast at about three hundred miles per hour.

A second witness, an assistant air inspector at the base, saw the second object separately. He estimated it was at fourteen thousand feet altitude and traveling at about the speed of a C-47 cargo plane. He watched it for roughly fifteen seconds before losing sight of it, then spotted it again briefly ten seconds later. He noted the object appeared larger than a typical weather balloon and described it as globular in shape with a dark blue color flashing in the sunlight.

The investigation turned up several leads. A weather balloon had been released from Hill Air Force Base at 1355 hours (1:55 p.m.), about ten minutes before the sightings. A second weather balloon was released from Salt Lake Municipal Airport at approximately 1400 hours (2:00 p.m.), very close to the time of the incidents. The Air Force also checked with Hinckley Field in Ogden and found no weather balloon had been released there that afternoon. The investigation included interviews with the witnesses and examination of weather records. An F-51 pilot who was flying in the area around the time of the sightings stated he did not see any light aircraft or other objects during his flight, though he noted he had been making wide circles around the field.

The Air Force file on this incident notes there was "no data presented to indicate objects could NOT" be explained, suggesting the official evaluation left the question unresolved. The full case file is reproduced below as it is held by the National Archives and spans 13 pages.