(Adds detail on US oceanographic survey ship)
By Ahmad Pathoni
MAKASSAR, Indonesia, Jan 7 (Reuters) - Indonesia deployed more troops and helicopters in the hunt for a missing airliner almost a week after it vanished from radar screens with 102 people aboard as anger grew among the passengers’ relatives.
Another 700 troops and four more helicopters were being used to look for the 17-year-old Boeing 737-400 operated by Indonesian budget airline Adam Air, said military spokesman Captain Mulyadi in Makassar on Sulawesi island, where search efforts are being coordinated.
Nearly 2,900 soldiers and police have been looking for the airliner along with at least four Indonesian military planes, a Singapore Air Force Fokker-50 and a helicopter.
A U.S. military aircraft arrived at an air base in Makassar to help the search, Lieutenant Joko from the air base said.
A US oceanographic survey ship with sonar capability and the the ability to detect metal under the sea, USNS Mary Sears, will arrive on Tuesday to join the search operations, the chief of the air base in Makassar, Eddy Suyanto, told a news conference.
"So far the result is nil. Tomorrow we will narrow our search in areas that we have covered," he said.
The intensified search came a day after relatives confronted the Indonesian vice president and called for more to be done.
"I won’t go home until they find the plane," Hendra Tuna, whose niece and her husband were among the passengers, said on Sunday. "This uncertainty makes us confused.
"Sometimes I still hold out hope but I am resigned to God’s will. I hope they find it soon so I can take my niece and nephew home in whatever condition they are."
The search had initially concentrated on areas of western Sulawesi, from where the last emergency signal was received, but was expanded to the north and east of the island on Friday.
"There is optimism but there is no guarantee," Mulyadi said, when asked about the chances of finding the plane.
NO DISTRESS CALL
The pilot made no distress call from the plane, which had taken off from Surabaya on Java island on Monday for Manado, provincial capital of North Sulawesi.
The only clue to where the stricken plane might have gone down came when a signal from its emergency locator beacon was detected by a Singapore satellite.
In his last conversation with Makassar air traffic control, the pilot said he had encountered cross-winds, officials said. Radar continued to track the flight for some time after that.
U.S. transport safety officials arrived in Sulawesi on Saturday and were working with Indonesian regulators investigating the disappearance.
"They have started work to collect data on the ground. We want to know why the plane disappeared from the radar," Setyo Rahardjo, head of the transport safety commission, told Reuters.
"If it had exploded, where is the debris? These are the questions that need answers."
On Saturday, Vice President Jusuf Kalla told relatives waiting in Makassar the government would spare no effort in its search for the missing plane, but they called for Indonesia to accept more help from abroad.
"We’ve been here for five days with only the clothes we are wearing," Yunus, whose cousin was on the plane, told Kalla. "If you ask us to pray, we have done it since day one. Why don’t we ask for more help from more advanced countries like the United States?"
The plane disappeared less than three days after a ferry capsized and sank off Java. Rescue officials said more than 230 people from the ferry had been rescued, leaving about 400 still unaccounted for.