Thirty aircraft parked on ramp, six in alert hanger, F-89 - Scorpions - KC 97's tankers were parked at other end of the ramp near other end of field. The guard was standing outside of alert hanger at the time the UFO approached from the north and hovered over the alert hanger, at about 1,000 feet, appeared as a round metallic looking object (called a flying saucer by the guard), no estimate of size is recalled, nor any other details on the object itself. The base radar about 1-1/2 miles distant picked up the object as did the FAA radar about five miles away across the city of Great Falls. Object was apparently hovering over the alert hanger and atomic missile and bomb storage building right near by. Object then slowly moved down the length of the runway, then moved across town (about 3 miles) to the 'Municipal Airport at Great Falls and hovered over the National Guard (F-89) parking ramp, then flew off. Communications between radar stations was being exchanged. Next day an investigator in civilian clothes came around asking all the base personnel questions about seeing anything unusual the preceding night.
Two more guards were inside the alert hanger at the time, but only the guard outside and possibly otlher quards around the field saw the object. Next day scuttlebutt was high in the conversation about the UFO among all personnel at the field. No details on color, lighting, sound, etc. are available on the UFO itself.
Source: Bay Area Subcommittee of NICAP letter, undated.