North of Fort Francis, Canada, July 1949July 1949

On July 1, 1949, a doctor and his wife driving north on Highway 70 near Fort Francis, Ontario, Canada, spotted what they believed was a flying saucer. They were roughly 50 to 75 miles north of Fort Francis, near the eastern shore of Lake of the Woods, when the wife noticed a silvery-gray, oblong object flying westward across the sky. The sighting lasted about five seconds.

The couple described the object as moving in a straight line but with an erratic, wobbling motion, like an elongated disc being tossed through the air. They estimated it was about 40 degrees above the horizon, or roughly as high as a small plane at 2,000 feet. The object appeared to move faster than an aircraft, made no sound, left no vapor trail, and had no visible fins or protruding parts. It vanished behind a line of trees.

The Air Force Office of Special Investigations interviewed the couple in August 1949. The doctor was established as a credible witness, with good standing in his community and no prior reports of disturbances. However, the investigation took an unusual turn when the doctor proposed that flying saucers might be connected to a polio epidemic then affecting Indiana. He theorized that some of his polio patients actually had uranium poisoning, possibly caused by radiation or a virus released from the saucers. Air Force officials forwarded this claim to medical experts for review.

The medical experts disagreed with the theory. A toxicologist at Indiana University confirmed that uranium poisoning has distinctive clinical features very different from polio, and noted that polio outbreaks have been common every summer for decades, long before flying saucers were reported. Medical staff concluded there was no credible link between the sightings and the polio epidemic, and that there was no evidence of radioactivity in any of the flying object cases. The Air Force file does not provide a final conclusion about what the couple actually saw.

The full case file is reproduced below as held by the National Archives, containing 13 scanned pages.