A flying saucer-shaped vehicle was sent high into the atmosphere via a balloon to trial a new type of parachute（降落傘） and an inflatable Kevlar ring that could help slow down a spacecraft as it approaches the Red Planet's surface.

All of the equipment appeared to work apart from the parachute, which failed to deploy fully.

The experiment was sent up from Hawaii.

Nasa hopes the lessons learned will enable it put heavier payloads on Mars in the decades ahead.

The current limit is about one-and-a-half tonnes.

If humans are ever to go to the planet, this mass capability will have to rise to well beyond 10 tonnes.

Saturday's test vehicle, known as the Low Density Supersonic Decelerator (LDSD), ditched in the Pacific after its flight.

Teams were despatched to try to locate the demonstrator so that its data recorder could be recovered.

This will give engineers the most detailed information on what precisely happened during the experiment.

Video cameras on the ground and on the LDSD captured most of the flight.