LAKENHEATH–BENTWATERS.
“On the night of August 13–14, 1956, multiple radar stations in eastern England — RAF Bentwaters, RAF Lakenheath, and RAF Sculthorpe — tracked a series of unidentified targets moving at speeds variously reported between 4,000 and 9,000 mph and at altitudes up to 60,000 feet.”
Royal Air Force Fighter Command scrambled an de Havilland Venom NF.3 night fighter from RAF Waterbeach. The Venom's airborne intercept radar acquired one of the targets at approximately 6 miles range. As the pilot, Flt. Lt. David Chambers, attempted to close on the target, the unknown apparently maneuvered behind the Venom — and then matched the pilot's evasive turns from the rear position for approximately 10 minutes despite the pilot's best efforts to reverse the geometry. Lakenheath ground radar tracked the cat-and-mouse movements throughout.
The case was investigated by US Project Blue Book and reviewed by the University of Colorado UFO Project (the Condon Committee) for its 1968 Scientific Study of Unidentified Flying Objects. The Condon Committee's principal investigator on the Lakenheath case, Dr. Gordon Thayer, wrote in the report's section on radar–visual cases that "in conclusion, although conventional or natural explanations certainly cannot be ruled out, the probability of such seems low in this case and the probability that at least one genuine UFO was involved appears to be fairly high."
Lakenheath–Bentwaters is one of the very small number of cases the Condon Committee — whose overall conclusions were generally dismissive of UFO reality — judged to be likely anomalous. The combination of multiple ground radar stations, an airborne intercept radar, ground visual observation, and the cat-and-mouse intercept geometry make it one of the most evidentially robust military UFO cases on record.