SYDNEY, Australia (AP) _ A French military plane dropped a life raft to American millionaire adventurer Steve Fossett today after the balloon he was trying to fly around the world crashed into the South Pacific.

The plane reached the site where the balloon went down near the Chesterfield Islands, about 500 miles off Australia's east coast, said French naval authorities in Noumea, New Caledonia.

But contact with Fossett was lost after he entered the last third of his voyage.

``No one has had radio contact, we do not know his condition,'' Robin Poke, a spokesman for the Australian Maritime Safety Authority, told The Associated Press.

The French plane circled Fossett until its fuel began to run low, and headed back to its home base in Noumea, Poke said. A Royal Australian Air Force Hercules C-130 was due in the region at any time, and will try to drop a radio to Fossett.

The Australian plane, which was also carrying emergency supplies, would remain with Fossett until a ship arrived or until its fuel ran low.

Three boats are in the area. A ketch, the Atlanta, was closest, Poke said. The New Zealand Navy tanker Endeavor was steaming to the rescue, said a spokesman on condition of anonymity.

Fossett had been two-thirds of the way through his effort. The balloon was 500 miles off the Australian coast heading toward its final destination of Argentina, in South America, when contact was lost, said Alan Blount, director of mission control for the journey at Washington University in St. Louis.

Seas in the area were relatively calm but the crew was concerned because the area is near a coral reef that could be full of sharks. It was shortly after midnight Australian time when the balloon ran into trouble.

Australian Maritime Rescue Center spokesman Brian Hill told Australian Broadcasting Corp. radio that Fossett came down near the Bellona Reefs, an uncharted region which could make ship navigation and the rescue difficult.

But a New Zealand Navy spokesman said they did not expect to have any problems making the rescue.

About five hours before Fossett's warning locator sounded, meteorologist Bob Rice had cautioned the balloonist he was approaching strong thunderstorms _ and that they would be nearly impossible to avoid.

``There's a good chance that there might have been a lightning hit on the capsule,'' Rice said. ``But these balloons are very strong. It's just too early to know what happened.''

Fossett was equipped with a wet suit and life raft, and the capsule of the balloon is seaworthy, but not leakproof.

Fossett had a long stretch of the Pacific Ocean between Australia and Argentina to go and had at least another five days of travel before he was expected to reach South America, which he left on Aug. 7.

Fossett, from Chicago, was making his fourth attempt to fly around the world.