Wurtsmith AFB, MichiganJanuary 1956

On the night of January 11, 1956, control tower operators at Wurtsmith Air Force Base in Michigan noticed an unfamiliar orange, circular object hovering near the runway approach. The object caught their attention because it seemed to be in an unusual location and had characteristics they could not immediately identify. They called for an F-89 fighter aircraft that was returning from another mission to investigate.

The radar observer aboard the F-89, Lieutenant William Freeland, obtained a radar lock on the target at an altitude of about 7,000 feet. The aircraft was closing on the object at approximately 50 knots of overtake speed (meaning the plane was catching up at about 58 miles per hour). The two parties maintained contact for roughly two minutes. Then the object began to climb steeply. The F-89 climbed to 11,000 feet trying to follow, but the target was ascending much faster and eventually disappeared from the radar scope entirely. The radar lock was broken and no further contact was made.

The investigating officer noted that the planet Venus was in a bright phase and positioned in the southwestern sky at the time of the sighting. However, he concluded it was unlikely to be Venus because control tower personnel said the object was noticeably dimmer than a nearby star they compared it to, and because an F-89 radar cannot achieve a lock on a celestial body. The investigating officer's superior suggested an explanation involving a temperature inversion (a layer of warm air trapped above cooler air near the ground). Such an inversion can bend radar waves in unusual ways, causing radar signals to reflect off the ground and appear as if they are coming from a target in the air. The officer concluded the sighting was probably caused by electronic and optical reflections due to these meteorological conditions.

The full case file, comprising 12 pages as held by the National Archives, is reproduced below.