KATMANDU, NEPAL, JULY 31 -- A Thai Airways jetliner carrying 113 people, including 11 Americans, crashed into a Himalayan mountain in heavy monsoon rains today minutes after the pilot reported a technical problem.

Airport officials said they doubted there were any survivors among the 99 passengers and 14 crew members. Flight TG311 from Bangkok to Katmandu, which was only half full, apparently was carrying mostly tourists.

{Nepali troops reached the site where colleagues had reported spotting the wreckage of the plane and found nothing, a senior police official told the Reuter news agency on Saturday. As a result of the report, police and army teams searching on foot had been ordered to fan out over a broader area, he said.

{An army foot patrol had reported spotting the wreckage from a distance Friday, but darkness and heavy monsoon rains prevented them from reaching the site until Saturday, he added.}

In eastern China, a Soviet-built Yakovlev-42 airliner with 116 passengers and 10 crew members aboard exploded in flames while taking off today from the Nanjing airport, killing 100 people and injuring 26, the state-run New China News Agency said. A 10-month-old baby was among the survivors.

The report said the plane, headed from Nanjing to Xiamen, on China's southeast coast, "failed to lift off and burst into a ball of flames" about 600 yards from the runway. The only foreigners on the plane -- four residents of Hong Kong and two of Taiwan -- were killed. The cause of the crash was under investigation, the news agency said.

Air traffic control at the Katmandu airport lost contact with the Thai Airways Airbus A310-300 near the village of Simra in the foothills of the Himalayas, 47 miles south of the airport, the airline said. Alerted by villagers, troops and policemen at a remote outpost north of Simra said they had located the wreckage in a forested area 8,500 feet high, the vice president of Thai Airways, Chatrachai Bunya-Ananta, told reporters in Bangkok.

The region is in central Nepal, 30 miles south of Katmandu. The crash site itself is a three-hour walk from the Shimbhjyng mountain pass, which connects Katmandu to the southern town of Bhainse. The pass snakes around hills and traverses steep mountains, some as high as 9,000 feet.

Nagendra Ghimire, the deputy airport manager in Katmandu, said the plane apparently slammed into the mountain in heavy rain as it was preparing to land. While he refused to say what could have caused the crash, Ghimire said the pilot reported a technical hitch when the jet was 15 minutes from Katmandu. A few minutes later, however, the pilot said the problem had been overcome.

" 'I am okay now and coming in to land from Simra,' " Ghimire quoted the captain as saying in the final contact. "After that there was no sign of the plane."

At about the same time, air traffic controllers in the Indian city of Calcutta, 400 miles to the southeast, also lost contact with the aircraft, officials there said.

News of the crash was delayed because of poor communications with the police outpost in the Chisapani jungle near the mountain pass.

In Bangkok, an airline statement said that besides the 11 Americans, passengers included 17 Japanese and 23 Nepalese. The plane also carried five Belgians, five Finns, four Germans, three Spaniards, two Thais, two Koreans, two Israelis, two Britons, two Canadians, one New Zealander and one Australian.

Thai Airways said the A310-300, built in November 1987, was leased in May 1990 from Blenheim Aviation. A spokesman for the San Francisco-based firm said the plane in fact was leased from a subsidiary, Bermuda-based Blenheim Air Lease Ltd. The manually operated A310-300 is an earlier model than the fully computerized Airbus A320, two of which crashed between 1988 and 1990, and a third earlier this year in eastern France.

The last crash involving a Thai Airways airliner was on Aug. 31, 1987, when a Boeing 737 plunged into the sea off the resort island of Phuket, Thailand, killing all 83 people on board. Errors by the pilot and control tower were blamed.