Blythe, CaliforniaFebruary 1953

On February 4, 1953, at 1050 Pacific Standard Time, the crew of an RB-36 transport aircraft spotted an unidentified object near Blythe, California. The plane was flying a ferry mission from Fort Worth, Texas to Travis Air Force Base in California when the sighting occurred. The RB-36 was flying at 20,000 feet with a true airspeed of 80 knots and a ground speed of 120 knots. The exact position at the time was 33 degrees 43 minutes north latitude, 115 degrees 16 minutes west longitude.

Multiple crew members observed the object over approximately five to ten minutes before it disappeared behind clouds. Crew members described it as a white, round object that appeared brighter than the clouds behind it. Some compared it to a full moon or a metallic surface reflecting sunlight. The object was estimated to be between 20,000 and 40,000 feet in altitude. Several observers noted that it appeared similar to a ball or moon in shape. One crew member estimated the object was about the size of an aircraft. The observers saw no vapor trails. The object made no definite movement or change of direction while being watched.

The crew members who filed statements about the sighting had slightly different views on the object's altitude and exact appearance, which the intelligence officer noted was due to each observer's different viewing angle from their positions on the aircraft. Despite these minor conflicts, the reporting officer found the sighting credible and worthy of investigation. None of the crew members thought the object was a conventional aircraft or a weather balloon.

The U.S. Air Force classified this case as unidentified. The full case file is reproduced below as held by the National Archives, 13 pages in total.