Project 10073 Record Card — Uzundzhovo, Bulgaria, 21 August 1957

On 21 August 1957, between 2000 and 2030 hours local time, a Turkish Army officer serving as an Assistant Turkish Army Attache observed an unidentified flying object near the Uzundzhovo Airfield in Bulgaria. The witness, who was traveling by automobile from Sofia to Edirne, Turkey, reported seeing a lighted object moving slowly at night near a military area. The object was being tracked by anti-aircraft searchlights, which would turn off and on as the object moved in a horizontal course. The witness noted that the airfield appeared to be completely blacked out during the event, and no other aircraft were heard or seen in the vicinity, with the exception of one jet that took off, climbed toward the object, passed it, and returned to the airfield. The witness, an artillery officer with twenty years of service, stated that he had significant experience with searchlight operations and was unable to provide an explanation for the event. The object was estimated to be at an altitude of 1000 to 1500 feet and traveling at a speed of 100 to 150 knots. No motor noise was heard, and there was no visible exhaust flame. The reporting officer, Lt. Colonel Joseph A. Burt, noted that while it was difficult to verify the event from the Zone of Interior (ZI), the circumstances strongly suggested a simulated anti-aircraft tracking exercise. It was hypothesized that the object could have been a balloon with a light attached, an illuminated aircraft, or a lighted sleeve target. The fact that a local jet intercepted the object and returned to the airfield led investigators to conclude that the pilot was aware of the object's nature, suggesting it was a controlled military training activity rather than an anomalous phenomenon.