American adventurer Steve Fossett has set off from Western Australia on his latest attempt to break a round-the-world record.

Mr Fossett took off from Northam, about 100 kilometres (60 miles) east of Perth at 0140 GMT after strong winds delayed his departure by several hours.

Flight of fancy

Journey time: 20+ days Distance: 29,000 km Speed: Up to 200 km/h Altitude: 7,000-8,500 metres Capsule size: 2.5 x 2.5 metres

It is his sixth attempt to be the first person to fly a hot-air balloon around the world single-handedly.

Last July he took off from the same farming town, and though he had to crash-land in Brazil 12 days later, it was the longest recorded solo balloon flight.

This time many modifications have been made to plans and equipment and Mr Fossett remained hopeful of success in his balloon named Spirit of Freedom.

Optimism

"I'm not confident at all, instead I'm optimistic," he said before take-off.

"I feel this is the best chance we've ever had."

The balloon, filled with helium and hot air, quickly climbed to 21,000 feet (6,400 metres) and was soon travelling at more than 50 knots.

By nightfall, Mr Fossett had travelled more than 150 km (95 miles). As the land cooled and the winds eased, the balloon dropped to 19,700 feet (6,000 metres), his mission control in St Louis, Missouri, said.

The balloon is expected to reach the Australian east coast within a day. If all goes well, it could reach Chile in six days.

The Spirit of Freedom has picked up an east wind

Mr Fossett plans to steer around bad weather over the Pacific and then rise to about 26,000 feet (8,000 metres) to pass over the Andes, mission control said.

Speaking from his capsule several hours after the launch, Mr Fossett said the flight was going much better than previous attempts.

The capsule measures 2.5 x 2.5 metres and is 1.6 metres high. Mr Fossett is breathing oxygen through a mask and eating military-style rations.

Northam was selected for the launch because it provides easy access into an easterly windstream.

It also gives Mr Fossett two days over land to make any adjustments before crossing the Pacific.

Mr Fossett, 58, has been lucky to escape with his life after some of his previous attempts went wrong:

• 1997: First try at solo circumnavigation ends in crash landing in Russia

• 1998: Storm shreds balloon, sends Mr Fossett plummeting 9,000 metres into the sea north-east of Australia

• 2001: Snow and ice threaten to rip balloon apart