The first test launch of what Japanese scientists hope will be the next generation of supersonic jet has failed in spectacular fashion in the Australian desert.

An 11.5-metre (38 feet) scale model of a plane intended to fly twice as fast as Concorde crashed into the ground shortly after taking off at a former rocket-testing range in South Australia.

The craft cost $80m to build

It was launched on the back of a booster rocket, but as it climbed to around 100 metres it began spiralling through the air before slamming into the ground and exploding.

No one was injured - neither the model plane nor the rocket were manned, but it marks a devastating blow for scientists who had spent the past six months preparing for the test.

The aim is to develop a jet with twice the range and half the noise of Concorde, which could fly passengers from Japan to the American West Coast in just four hours.

Twice the speed of sound

The team, sponsored by the Japanese Government's National Aerospace Laboratory, had hoped that the booster rocket would carry the aircraft 20 kilometres above the launch site near Woomera in South Australia.

It exploded on impact

The plan was then to release the model - one-tenth of the size of the planned jetliner - which would then glide back to base at more than twice the speed of sound.

But just seconds after launch, the craft flipped over and began its erratic spiral down to earth.

The cost of building the model was $80m and the Woomera test alone, the first of four planned over the coming nine months, cost $7m.

Cause unknown

The Japanese project team has made no statement about why the rocket might have crashed.

The launch had been postponed several times because the wind was too strong in the desert.

The team had planned the test for six months

The project aims over the next decade to build a new range of supersonic aircraft to succeed the Anglo-French Concorde, which entered service in the 1970s.

The NEXST1 would provide a significant improvement on Concorde's performance, researchers believe.

It would carry 300 passengers, triple Concorde's payload, with twice the flying range and a 75% reduction of fuel emissions.

Developers, who include Mitsubishi and Nissan, hope that the new supersonic plane will have noise levels similar to the Boeing 747.

That would mean that it would be able to operate far more widely than Concorde, which is notoriously noisy.