Nellis AFB, NevadaApril 1962

On the night of April 19, 1962, radar operators at Nellis Air Force Base in Nevada detected an unidentified blip on their scopes. The object appeared on both the search radar (a wide-area detection system) and the height finder radar (which measures altitude), confirming that something real was out there. No pilots saw the object visually, and no aircraft were in the area at the time.

The radar blip moved across the sky in an unusual way. Its speed varied noticeably as it traveled. The object first appeared at an elevation of 060 degrees (looking upward from the horizon at a steep angle) and disappeared at 105 degrees azimuth (looking roughly west-southwest) at an altitude of 10,000 feet. Witnesses reported the object heading northeast at approximately 258 degrees before vanishing instantly to the south. The entire sighting lasted thirty-two minutes.

The radar operator who spotted the blip, A2C Kenneth A. Colatruglio of the 855 Radar Squadron, was considered reliable by his commanding officer, Captain Dwight S. Ranney. The sighting occurred in the same general area as the Nellis weather station, and no other aircraft or radar returns were detected nearby during the incident. However, the scope camera was not operating at the time, so no photographic record was made.

Air Force investigators found the evidence puzzling. Their official comments stated there was not enough information in the report to reach a firm conclusion, but they noted that the object's track characteristics resembled those made by a U-2 spy plane or a high-altitude balloon. A declassified letter from September 1962 reiterated this assessment, stating "there is insufficient data reported to fully support such an evaluation." The case was ultimately marked as unknown.

The full case file, containing 8 pages, is reproduced below as held by the National Archives.