E of Monticello, IllinoisJuly 1961

# Summary

Three people driving west on a highway near Monticello, Illinois, in July 1961 saw lights in the sky that appeared to keep pace with their car. The observers reported seeing two bright lights in front and one in the rear. The lights remained visible for about two minutes before fading away. The witnesses said they could not hear any sound and described themselves as quite excited by the experience.

Investigators from Chanute Air Force Base checked the sighting and discovered that a Comanche-type light aircraft had been landing at a nearby airfield around the same time. The aircraft had landing lights on its wings and an additional light on its nose gear. Investigators concluded the aircraft's lights, combined with the witnesses' movement and the poor visibility conditions that night, likely explained what the three observers had seen. The aircraft was probably circling for a landing while the car traveled west at 50 to 60 miles per hour. As the car began turning from west to east, the plane's ground speed and the car's speed became roughly equivalent, which would explain why the lights appeared to maintain their relative position.

The Air Force evaluation marked the sighting as "probably balloon," though the case file text clearly indicates the investigation pointed toward an aircraft explanation. The full case file is reproduced below as held by the National Archives, consisting of 8 pages.