London, Oct 28 : US Aerospace company Rocketplane Global has unveiled a new, roomier design for its suborbital space place, which it plans to put in service by 2010.

The Oklahoma based firm’s original concept used a modified Lear jet that was to ignite a rocket to reach the edge of space

But engineers realised that about 95 percent of the jet's main body would need to be altered to make the vehicle fit for rocket-powered spaceflights.

So now they have created a completely new design for the jet.

The rocket engine will ignite at an altitude of 12 kilometres, taking passengers to the edge of space at 100 kms. For the first few flights, passengers will have to remain strapped to their seats during the weightless portion of the trip.

The company has said its new Rocketplane XP vehicle is lighter and has more cabin room, allowing it to carry five passengers in addition to the pilot, compared to three passengers in the previous design.

Officials said the new design also uses jet engines with more powerful thrust, allowing the vehicle to reach an altitude of 12 kilometres (40,000 feet) before igniting its rocket engine.

Previously, this rocket firing occurred at a much lower altitude - about nine kilometres (29,000 feet).

Rocketplane now plans to begin testing the vehicle's kerosene-fuelled rocket engine within the next year.

Test flights are planned for 2010, with passenger flights beginning soon thereafter, assuming everything goes smoothly with the tests.

“We're hoping to be in commercial operations by the end of 2010,” said Rocketplane Global's spaceplane programme manager, David Faulkner.

According to the New Scientist magazine, a ticket will cost 250,000 dollars for the first 50 seats, with the price dropping to 200,000 dollars after that.

Rival company Virgin Galactic, which will use a design based on the X Prize-winning SpaceShipOne, has said it will charge its first passengers 200,000 dollars for a trip to the edge of space.

But unlike Virgin Galactic, Rocketplane Global will - at least initially - not allow passengers on the XP to leave their seats and float freely during the microgravity part of the flight, which will last three to four minutes.

Former NASA astronaut John Herrington, who is the company's director of flight operations has said it could be difficult for passengers to manoeuvre in microgravity well enough to get back to their seats quickly for the return to Earth.

“I'm not going to let people get out of their seats right off the bat,” he said. (ANI)