|During the 1930s British scientists working on a ‘death ray’ discovered that when radio waves from a transmitter struck targets such as aircraft, ships and buildings they bounced back and could be detected by a receiver. The Air Ministry quickly began to develop a functioning early warning system that could be used to calculate the distance, direction and height of German aircraft by listening for the echoes returned from bursts of radio waves. Originally known as a Radio Direction and Finding (RDF) the term ‘radar’ was adopted during WW2 when the Chain Home system, built around the English coastline, was||
By David Clarke
the key to the success of the RAF during the Battle of Britain. But despite its success early radar systems were cluttered by noise from birds, insects, weather systems and unusual atmospheric conditions. Here are some of the most common explanations for UFOs on radar:
|Chain Home Radars at RAF Poling, Sussex WW2|
This is caused by unusual meteorological conditions that trap and bend radio waves along the surface of the Earth. AP can result in radio energy being returned from objects at distances far in excess of the radar’s normal range of operation. On occasions moving objects such as cars, ships and low-flying aircraft have been superimposed on the usual radar picture. AP may be the ultimate source of some classic radar UFO flaps including those that plagued Washington DC during the summer of 1952 and RAF Bentwaters-Lakenheath in 1956. Measurements of extreme speed and height of anomalous radar targets is completely worthless if the observer is unaware that AP is present and even experienced operators have been fooled. More recently, clear air radar echoes created by backscattering from fluctuations of the index of refraction in the atmosphere have been detected by scientists using powerful radars operating at several wavelengths.
One of the pioneers of radar meteorology, Dr David Atlas (1924-2015) said these experiments prove ‘the atmosphere will effect radar propagation in almost unbelievable ways and produce virtual targets which have apparently fantastic maneuverability’. In 2002 Dr Atlas said the majority of UFO radar incidents occurred before the results of NASA-sponsored research using extremely sensitive radars to probe extremely thin atmospheric echo layers was widely known.
These experiments at Wallops Island in Virginia from 1967 identified ‘incredibly thin, specular reflecting layers like mirrors at high altitudes…that could account for the exceedingly large apparent speeds of echoes either from ground targets or moving vehicles on the ground’. He added:
‘I am strongly convinced that these mysterious radar echoes are due to anomalous propagation somewhat different than that with which scientists in the 1950s and 60s were familiar’. He believed the large number of UFO radar reports during this period ‘was due to the lack of knowledge of their origin. Once their origin was explained the frequency of the reports decreased’.
A secret CIA-MoD experiment with Palladium might explain the radar UFO reported by USAF F-86 pilot Lt Milton Torres who was sent to investigate a blip detected by RAF radars in East Anglia one night in 1956-57. Torres’s airborne radar locked onto the ‘object’ that appeared to be the size of a B52 bomber and he was ordered by the ground controller to open fire with his salvo of rockets. But ten seconds before he received authentication the ‘bogey’ broke away and disappeared at great speed. There was no visual sighting. On return to base Torres was debriefed by a secret service agent and told his mission was Top Secret. He did not discuss it again until 1986 after retirement from USAF.
|Track of aerial phenomena seen on radars at RAF Ventnor in July 1957 (TNA AIR 2/19994)|
These UFOs were designated as ‘X-raids’ and, if they could not be identified as friendly aircraft, RAF fighters were scrambled to intercept them. This tracing sheet was produced by Flt Lt J.S. Hassall to record the movements of strange aerial phenomena tracked by radars at RAF Ventor, Isle of Wight, on the afternoon of 29 July 1957.
In his report to the Air Ministry’s UFO branch, DDI (Tech), Hassall said his Type 80 radar first plotted ‘X-raid 422’ moving at speeds between 1000-1400 knots at a height of 42,000 feet above the English Channel. Minutes later Hassall tracked another similar echo, moving at a similar speed, then a third and a fourth. By then he had begun to doubt the tracks were genuine. His report concludes:
‘It was finally decided these were spurious responses, but as they had been designated X-raids, recordings and reports were made’. [TNA AIR 20/9994]