A fishing boat Saturday rescued a Japanese adventurer from the ocean where he ditched his gondola after failing to complete the first solo trans-Pacific balloon crossing, Japanese and U.S. officials said.

Fumio Niwa, who embarked Tuesday on a 4,970-mile trip from Yokohama to San Diego, landed his "Toss Pacific" balloon in the ocean about 425 miles east of Minami-Tori Shima (Southern Bird Island), one-third of the way towards his goal, Japanese officials said.The Japanese Maritime Safety Agency said its patrol plane spotted Niwa shortly after he radioed that he was ditching his gondola, which floats.

Several hours later, Niwa was picked up by the Japanese fishing vessel Yusuei Maru No. 1, said Petty Officer Gary Jensen of the Coast Guard Joint Rescue Coordination Center in Honolulu.

Niwa was reported in good condition when he was rescued, Jensen said. Earlier, the 38-year-old balloonist said he was seasick from the waves tossing around the globe-shaped gondola and Japanese officials assured him help was on the way.

Niwa decided to descend after about 1,900 miles because he was caught in a sub-tropical lull, "something that doesn't normally occur in February," said Gary Kolman, of Toss International Inc. of Escondido, Calif., a sponsor of the trip.

His failure to reach San Diego, Yokohama's sister city, on a goodwill mission celebrating Yokohama's centennial "didn't have anything to do with mechanical or engineering problems," Kolman said.

"Mother Nature just didn't cooperate," Kolman said. "If he had caught the winds as anticipated, he would have been right on target."

Niwa had planned to ride his 56-foot helium balloon along a 150-mph winter jet stream over the Pacific.

Problems surfaced two days into the voyage when Mina, riding the tail end of the jet stream, "suddenly went right out of it and wound up in an 800-mile lull, just still air," Kolman said.

Niwa also experienced difficulties with swelling and contracting of the balloon's helium and with altitude control.

"I dropped sand used as ballast last night to bring the balloon back on the right course as it veered south, but the sand was frozen and stuck on the gondola's body," Mina was quoted in a radio message to project supporters in Yokohama.

"Most of his ballast was gone and the wind had died to a low level," Kolman said. "For every step he took forward, he took two steps back. He eventually was taking a long stairway down to the ocean."

Niwa, a former computer worker and longtime balloonist, "had dreamed of this trip since childhood," Kolman said.