The BBC's James Wilkinson: "It doesn't look like a bike at all"

Engineer Richard 'Rocketman' Brown believes his hand-built, rocket-propelled Gillette Mach 3 Challenger can smash the current record of 332mph and could touch 500mph.

The 8m-long machine resembles a missile on wheels but needs to be supported by retractable stabilisers as it is towed by car to 60mph. Only above this speed does it have enough forward momentum to stay upright.

"It's actually a fairly violent thing to drive," said Mr Brown.

Richard Brown: "It's a hell of a ride"

"You need your wits about you, but it's a hell of a ride."

Mr Brown says the top speed of his 6,000-brake horse power bike - roughly equivalent to 10 Formula One cars - is not yet known.

"Every time I drive it I think, 'this is more powerful'. It never ceases to amaze me," he said.

Mr Brown has come up with a completely new design since his first failed attempt at the record on a conventional motorcycle two years ago.

Mechanics prepare the rocket motor

He described the additional benefits of the rocket bike design, which allows him to drive the machine from a seat inside a heavy duty roll cage, rather than in the biker's usual exposed 'jockey' position.

"Being rocket-powered has enabled us to put all the components and fuel cells both in front and behind the driver, rather than around him.

"The constraint that has determined the shape of it has been the size of me," he said.

The first attempt hit 200mph

During testing on an airfield in Yorkshire, Brown's bike has been achieving 0-150mph in just three seconds, placing it well on target to shatter the standing British and world records.

He plans to break the British motorcycle land speed record of 209mph and the outright British land speed record of 215mph. Then he will try for the world land speed record for a two-wheeled vehicle in the US.

In 1997, Richard Noble's Thrust SSC car took the outright land speed record back to the UK. He also drove the first vehicle to break the sound barrier on land with a speed of 763.035mph set in Nevada's Black Rock desert.