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• 'Like a mini-spacecraft'
• Window of opportunity
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ALICE SPRINGS, Australia (CNN) -- Another attempt to fly around the world in a balloon is expected to get under way Tuesday, barely a week after one led by British tycoon Richard Branson ended in failure near Hawaii.

The U.S.-Australian team preparing to launch will not only shoot to be the first in 21 tries to circumnavigate the globe, it also plans to hit the stratosphere.

At 39 kilometers (24 miles), Team ReMax hopes to fly a manned balloon higher than any other before it.

"In the stratosphere, there is no significant weather features, so once we get up there we won't get the storms that have brought down previous attempts," said Dan Pederson, a former U.S. Navy test pilot and the team's mission control director.

Weather is what brought down Branson and his fellow balloonists, U.S. millionaire Steve Fossett, and Per Lindstrand of Sweden. They ditched their balloon in the Pacific Ocean Friday, half-way to their goal, when they ran into a low-pressure system they could not get around.

Pederson said that the Team ReMax balloonists -- Australian national balloon champion John Wallington, U.S. real estate magnate Dave Liniger and U.S. television science reporter Bob Martin -- won't be running into a wall of weather. But their unprecedented height will bring other challenges.

"I think from our perspective the most danger is the life support system," he said. "Once the human body gets above 50,000 feet (15,000 meters), the atmosphere is not what it is at the surface of the earth. So once you get up above that, all the life support is artificially built and it's got to keep them alive up there."

"Our equipment has to be like a mini-spacecraft," said Wallington, who was the first to fly a balloon 2,480 miles (3,993 km) across Australia, with Dick Smith in 1993.

Inside their 7- by 8-foot (2- by 2.5-meter) capsule, the three pilots will wear Russian made Sokol space suits -- the type used in Soyuz and Mir missions.

The team -- sponsored by Liniger's ReMax International -- will launch their 40-story polyethylene balloon from a weather-balloon launching facility in the middle of the Australian outback. While the weather isn't expected to be a factor during the approximately 22,800-mile (37.000-km) flight, it can affect the take-off and landing.

With that in mind, Liniger's team has set a launch for December 29 -- weather permitting.

"There are two fronts moving in that could kick up the winds," Liniger told the Denver Post. "We're due to get more refined weather data that will go 36 hours out."

Ideal weather conditions are forecast for the launch site through mid-January.

The team hopes to land near Alice Springs 16 to 18 days after launch -- after becoming the first to make it around the world.

Wallington said he looks forward most of all to the landing.

"To be absolutely honest," he told the Denver Post, "I just want to get around and down."

Correspondent Michael Holmes contributed to this report.