By Joseph Kolb
ALBUQUERQUE, N.M., Jan 24 (Reuters) - Two balloonists took flight from Japan on Saturday in a bid to break world records for distance and duration for gas balloon travel, in what they hope will be at least a six-day trans-Pacific flight reaching the U.S. West Coast, officials said.
The distance record of 5,209 miles (8,383 km) for gas balloons was set on the only previous manned trans-Pacific flight, in 1981, while the duration record of more than 137 hours aloft was set in 1978 by a team crossing the Atlantic.
"It goes to the philosophy of man," said Ray Bair, an official observer with the National Aeronautic Association based at Mission Control in Albuquerque, New Mexico. "You always try to attain new heights and distances. That's what this is all about."
The balloon, which relies solely on an enclosed chamber of helium gas for lift, is different from hot air balloons and so-called Roziere balloons, which rely on both hot air and lighter-than-air gas.
Roziere balloons have by far the greatest range of the three types.
Balloon pilots Troy Bradley, an American, and Leonid Tuikhtyaev, of Russia, collectively dubbed "Two Eagles," successfully took off after bad weather and poor wind trajectories had repeatedly delayed their launch, Bair said.
They will subsist on a diet that includes fresh fruit, freeze-dried hikers' meals, beef jerky and the occasional hot meal prepared on a small stove, and will be equipped with cold weather gear including sleeping bags and a heater.
If they make it to the U.S. West Coast south of Oregon they will have broken the distance record, Bair said, adding that they could also attempt to fly further, as the craft is believed capable of staying aloft for 10 days. (Editing by Jonathan Kaminsky and Leslie Adler)