Group /Category 9 - Radar Case

Dr. James E. McDonald:
Just to cite briefly another example of a radar-visual sighting in the official unidentified category: the December 6, 1952, airborne sighting by the crew of an Air Force B-29 flying over the Gulf of Mexico at 18,000 feet in bright moonlight. More than six separate unknowns, seen on the B-29 radarscopes and by crewmen watching out side-blisters, passed at high speeds estimated at 5,000 mph from blip displacements.  Some of them were seen below the flight altitude, and others maneuvered in most unconventional patterns such as sudden course-reversals.  No meteor explanation would fit the visual sightings, and ground-return effects are essentially out of the question by virtue of the high altitude and by the features of the atmospheric laps rate at the time and area of this unusual sighting.  It remains an unidentified in USAF files. 

Francis Ridge:
There is little more to add to what Jim McDonald has stated above, except that this case report is item #8 on the list of 41 formerly classified Air Technical Intelligence UFO sightings cleared for Maj. Donald E. Keyhoe by Albert M. Chop, Air Force Press Desk.