Rocket woman builds 300mph jet car in her back garden

Speed demon Carolynne Campbell has built a 300mph rocket car in her back garden that goes from 0-100mph in less than half a second.

The fearsome motor is 10 times more powerful than Lewis Hamilton's F1 car.

Its four hybrid rockets are fuelled by nitrous oxide and bio-fuel and produce a total 8,000lbs of thrust - equivalent to the power of a Red Arrows jet fighter.

Carolynne, 57, has spent £40,000 and five years designing and building the 400kg monster from scratch. She had to apply for an explosives licence before firing up the engines - which reach an incredible 2,500 degrees C.

Carolynne started the dream project with partner David Knight, 64, after seeing a dragster car fitted with a rocket at the Santa Pod race track, in Northants.

But David was forced to take a back seat after he was diagnosed with a brain tumour, leaving designated driver Carolynne to do the bulk of the construction.

The full-time carer, from Rushden, Northants., who is trained in graphic design, has been tinkering with cars since she was a child.

She managed to muddle through with the advice of David who has been involved in drag racing and building cars for 30 years.

She said: 'I've mucked around with cars and engines since I was a kid, and I studied design, so between us, we worked it out.

'Our original model had just one engine but I thought it was a bit slow, so instead of just one rocket, we've fitted four.'

The car - called 'Laffin Gas' - costs £500 to take for a spin, using 35kg of nitrous oxide.

Carolynne's hybrid rockets are fired into life by a small firework that ignites nitrous oxygen, splitting the oxygen and nitrogen into separate gases.
The oxygen burns a solid fuel, rape seed oil, that is soaked into dense cardboard tubes.

Carolynne can throttle up and down and shut the rockets off quickly by controlling the flow of liquid nitrous into the rocket.

The chassis of the car is made of aeroplane grade aluminium, titanium and chromium molybdenum steel. It is brought to a halt with two parachutes.

Constrained by the cost, Carolynne only puts Laffin Gas through its paces four or five times a year on a quarter mile dragster track at the Shakespeare County Raceway, Warwickshire.

She has so far reached speeds of 200mph but hopes to hit 300mph on their next trial in January - which would make her the fastest woman in UK.

Carolynne is unfazed at driving at high speeds.

She said: 'I get nervous before I drive but only because we always have spectators and I worry the rockets won't work.

'Its actually quite a smooth ride and not too noisy.'

Financing Laffin Gas - which would have cost £250,000 if built by professionals - has been a struggle, especially after David was diagnosed with a brain tumour in 2004.

The mechanical engineer has since undergone seven operations to remove the tumour which have damaged his short term memory and impaired his movement.

The money for materials and fuel has come from restoring and selling old cars and motorbikes.

Essential safety equipment, such as a helmet and a fireproof suit has been donated by well wishers.

Carolynne said: 'Working on the car and raising the dosh to buy parts has helped me take my mind off David's illness.

'I used it as a form of stress relief to cope with visiting him in hospital every day.'

Carolynne hopes to be able perform with the rocket car in the future, touring Europe.