By Meirion Jones
The UK knows more than it is saying about top secret American aircraft projects, recently declassified documents reveal.
Deep inside a previously secret Ministry of Defence report are a few pages which will reignite one of the biggest internet conspiracy questions - Is the US Air Force building secret spy planes which can cross the sky at 3,000mph?
The plane, which is often referred to as Aurora, is supposed to be a follow on from the U2 spy plane and the
2,000mph SR71 Blackbird, both of which were first developed and flown in secrecy as 'Black' projects.
The MoD report from 2000 says the USAF plans to produce "highly supersonic vehicles at Mach 4 to 6" and hypersonic unmanned craft which will fly in the upper atmosphere and in space. In 2003, the USAF revealed it had been working on a hypersonic unmanned craft - the Falcon - but denied building an Aurora-like Mach 4 to 6 aircraft.
The Aurora has 100,000 web pages devoted to it - a lot for an aircraft which may not exist.
According to Jane's Defence Review a third of USAF spending on research and development and procurement goes on classified projects. Some of that helps pay for the development of spy satellites and intelligence activities. But a sizable proportion goes on the development of secret manned and unmanned aircraft.
For more than 50 years some of the world's most exotic aircraft have been developed at Groom Lake in Nevada - otherwise knows as Area 51 - where the appearance of strange shapes in the sky - planes which officially did not exist - led to rumours that captured UFOs were being flown out of there by the US military.
The U2 first took to the sky at Groom Lake in 1955 and stayed secret for five years till the Russians shot one down over Svedlovsk and captured the pilot Gary Powers.
The Blackbird SR71 spy plane also secretly flew from Groom Lake in the early 1960s and the F117 Stealth Fighter and its prototypes flew from there for ten years before they were publicly revealed.
Huge projects have been hidden from public gaze. The USAF spent $20 billion in developing the B2 stealth bomber before revealing it.
Millions were spent upgrading Groom Lake ten years ago and all the surrounding high ground which overlooks the base has been fenced off to keep out curious onlookers but apart from a couple of stealth prototypes there is no sign of what the USAF has been working on there since.
The MoD report which was produced in 2000 and originally classified "Secret - UK eyes only" deals with UFOs - or UAPs (Unidentified Aerial Phenomena) in MoD jargon - and concludes that there is no evidence for the existence of alien visitors.
Gary Powers was shot down in a U2 over Soviet airspace in 1960
But it includes a working paper on 'Black' projects which says "it is acknowledged that some UAP sightings can be attributed to covert aircraft programmes". The report lists three Western programmes.
The first is the SR71 Blackbird which it refers to by its little-used code name 'Senior Crown'. A 14-line description of Programme 2 and a ten-line description of Programme 3 are both withheld.
Even the names of the programmes have been redacted on the grounds of 'international relations'. There are pictures of stealth fighters and bombers, the Blackbird and the new American F22 fighter but two photographs have been withheld. Could one of these be a picture of Aurora?
Bill Sweetman of Jane's Defence Review has been analysing America's undercover defence projects for fifteen years. We showed him the report and he concludes the MoD "identified two separate US 'Black' programmes that might have operated from the UK. It could be something they have reason to know about".
The blanked out sections might well contain a reference to Aurora but that does not mean the plane definitely exists. Sweetman says the blanked out sections "could be speculation but then why would they need to withhold it?"
Elsewhere in the document in a section on exotic technologies is another intriguing line. The DIS say "The projected (USAF) priority plan is to produce unpiloted air-breathing aircraft with a Mach 8-12 capability and transatmospheric vehicles." but it then continues "as well as highly supersonic vehicles at Mach 4 to 6".
The MoD report will be seen by Aurora chasers as another clue to put with unexplained sightings and mystery sonic booms but the Pentagon still insists that Aurora is a figment of their imaginations.
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