N Of Baltimore, Md., October 1958October 1958

On October 26, 1958, two men driving near Loch Raven Dam north of Baltimore, Maryland spotted a large, flat, egg-shaped object hovering between 100 and 150 feet above a bridge. As their car approached to within about 75 to 80 feet of the bridge, the vehicle's electrical system failed. The engine stopped, the dashboard lights went out, and the headlights died. Both men got out and hid behind the car.

For 30 to 45 seconds, they watched the object glow with an iridescent white light. Then it flashed brilliantly, the men felt heat on their faces, and they heard a loud noise they described as somewhere between a rumble and an explosion. The object rose straight up into the sky, becoming brighter and its edges more blurred as it climbed. It disappeared completely within 5 to 10 seconds. After the object vanished, the men turned their car around and the engine started normally.

The witnesses drove to a nearby phone and tried calling the Ground Observer Corps (a civilian network that reported sightings to the Air Force), but the person who answered was dismissive. They then called the Towson Police Department. While talking to police, both men noticed burning sensations on their faces. They went to St. Joseph's Hospital in Baltimore for examination. A doctor found that one man's face was slightly red and gave them a brief checkup, concluding they had nothing serious to worry about.

The Air Force investigation found that several reliable witnesses in the area had also heard the loud noise on the evening of October 26, though they did not see the object. The bridge itself was a double-arched steel structure about 500 feet long. Weather conditions were clear with good visibility. The investigator concluded the object's 100 to 150 foot altitude ruled out aircraft, and natural causes like fluorescent gases could be ruled out because of the noise involved. The full case file, comprising 36 pages, is reproduced below as held by the National Archives.