Phileas Fogg, the fabled British adventurer who traveled "Around the World in 80 Days" in the Jules Verne classic, might be envious of the derring-do of today's high-tech, hot air balloon trips.

In the remote town of Miyakonojo in southwestern Japan, the countdown began Tuesday for the liftoff of the world's biggest ever hot-air balloon -- taller than the Statue of Liberty and wider than a 747 -- which plans to sail the jetstream across the Pacific to the United States in less than 50 hours.

Briton Richard Branson, chairman of Virgin Atlantic Airways, and Swedish balloon designer Per Linstrand, hope to fire up the propane burners in their pressurized gondola the size of an Apollo space capsule.

If all goes well, the mammoth silver-colored balloon will reach the sub-tropical jetstream at 31,000 feet about an hour after liftoff and be carried at up to 200 mph in a direct shot to either Northern California or Southern Oregon in 30 to 50 hours.

Branson and Linstrand, who teamed up to cross the Atlantic in a much smaller balloon, will be attempting the first Pacific crossing in a hot-air balloon, a distance of some 6,200 miles. The helium-filled Double Eagle V, piloted by Ben Abruzzo, became the first manned balloon to make the trans-Pacific flight from Japan to the United States, ending in a crash-landing in rugged Northern California mountains.

"We are 90 percent confident of a launch at 6:30 a.m. Thursday," said project spokesman Mark Harvey. "If everything goes smoothly, we will cross north of San Francisco for a landing either in Northern California or Southern Oregon," he said. While enabling the balloon to travel at much higher altitude and greater speed than the helium-filled craft, it poses greater danger.

"If we don't enter the jetstream correctly, the balloon can be torn apart by winds pulling at the craft from different directions, called 'wind shear,"' Harvey said. "The most critical part of the flight is the first 90 minutes as we enter the jetstream. That is when technical failure is most likely to occur," he said.

He said, "When I do a balloon release, I use only pure latex balloons, which are colored with small amounts of non-toxic coloring. Because they are made of latex, a natural plant extract, they will degrade naturally. I do not use any plastic clips to seal them; they are sealed by tying a knot in the neck. I do not tie plastic ribbon to the balloons, and I discourage any of my customers from using string of any kind on balloons for release."