So secret, its existence is not even acknowledged

The origin of the mysterious bangs heard across the UK and New York at the weekend are yet to be officially identified.

But a leading theory is that they were created by an aircraft possibly travelling at supersonic or hypersonic speeds above the Atlantic.

This has led conspiracy theorists to attribute the booms to a spy plane rumoured to be under development by the US military, under the codename Aurora.

Dr Bhupendra Khandelwal, an engineering research associate from Sheffield, claims the loud bangs were created by a type of experimental jet engine called a pulse detonation engine.  

Claudia Angiletta, a resident from Croydon, South London, recorded the sounds as she was watching TV at home at around 10pm GMT on Saturday.

It could be a successor to the Mach 3.35 Lockheed Martin SR-71 Blackbird craft that was retired in 1998.

By comparison, extreme reports claim the Aurora could hit up to Mach 11.8.

These claims originated in Aviation Week and Space Technology magazine, which ran an article in 1989 about a mysterious entry in the 1985 US budget.

The entry said $445 million was attributed to 'black aircraft production' under the name Aurora.

These reports did not reference a single craft, instead they discussed a series of planes.

Other reports suggest the Aurora programme kicked off at Lockheed Martin's Skunkworks in 1987.

The firm was said to be looking into replacing its SR-71 Blackbird, which was later retired in 1998.

However, the former head of Lockheed's Skunkworks division, Ben Rich, said Aurora was a codename for the stealth project which eventually led to the B-2 Spirit.

But, in November 2013, Lockheed Martin announced it was developing a spy plane with similar technologies called SR-72.

The firm said the plane can accelerate up to Mach 6, or 4,567mph (7,349km/h) - three times faster than Concorde.

Concorde flew no faster than Mach 2, primarily because the materials weren’t available in the Sixties that could withstand greater heat.

Technology has advanced since then, and the SR-72 will be a so-called ‘warm structure’ - it will heat up rather than reflect the heat using the sort of ceramic tiles that covered the Space Shuttle.

Concorde wasn’t allowed to fly supersonic over land because of the ‘sonic boom’ - the sound associated with the shockwaves created by a craft moving faster than the speed of sound.

(dailymail.co.uk)

ANN.Az