Ships race to search for jet signals

PERTH, Australia – A British navy ship with sophisticated sound-locating equipment arrived today in a patch of the southern Indian Ocean to determine whether underwater sounds picked up by a Chinese ship crew using a hand-held device came from the missing Malaysia Airlines black boxes.

Britain reported the HMS Echo had arrived in the new area. It will be in a race against time to determine what the noises are, because the battery-powered pingers that emit sounds from the black boxes are on the verge of dying out.

Meanwhile, the Australian navy ship Ocean Shield, which is carrying high-tech sound detectors from the U.S. Navy, was investigating a sound it picked up in another area about 345 miles away. Australian authorities said once it had finished that investigation, it would head the new area to help the HMS Echo.

Hopes of finding the plane were given a boost after a Chinese ship picked up an electronic pulsing signal on Friday and again Saturday. The Ocean Shield detected a third signal in the different area Sunday, the head of the multinational search said.

The two black boxes contain flight data and cockpit voice recordings that could solve one of the most baffling mysteries in modern aviation: who or what caused Flight 370 to veer radically off course and vanish March 8 while traveling from Kuala Lumpur, Malaysia, to Beijing with 239 people on board.

But there were questions about whether any of the sounds were the breakthrough that searchers are desperately seeking or just another dead end in a hunt seemingly full of them, with experts expressing doubt that the equipment aboard the Chinese ship was capable of picking up signals from the black boxes.

“This is an important and encouraging lead, but one which I urge you to treat carefully,” said retired Australian Air Chief Marshal Angus Houston, who is coordinating the search.

He warned that the sounds were “fleeting acoustic events,” not the more extended transmissions that would be expected.

“We are dealing with very deep water. We are dealing with an environment where sometimes you can get false indications,” Houston said. “There are lots of noises in the ocean, and sometimes the acoustic equipment can rebound, echo if you like.”

But time is running out. The devices emit “pings” so they can be more easily found, but the batteries last only about a month.

China’s official Xinhua News Agency reported Saturday that the patrol vessel Haixun 01 detected a “pulse signal” Friday at 37.5 kilohertz – the same frequency used by the airliner’s black boxes.

Houston confirmed the report and said the Haixun 01 detected a signal again on Saturday within 2 miles of the original signal, for 90 seconds.

The crew of the Chinese ship reportedly picked up the signals using a sonar device called a hydrophone dangled over the side of a small boat – something experts said was technically possible but extremely unlikely. The equipment aboard the British and Australian ships is considered far more sophisticated.

A senior Malaysian government official said Sunday that investigators have determined that Flight 370 skirted Indonesian airspace as it flew to the southern Indian Ocean.

The official, who spoke on condition of anonymity because he was not authorized to talk to the media, said Indonesian authorities confirmed that the plane did not show up on their military radar. The plane could have deliberately flown around Indonesian airspace to avoid detection, or may have coincidentally traveled out of radar range, he said.

Houston said there had been a correction to satellite data that investigators have been using to calculate the plane’s flight path. As a result, the southern section of the current search zone will be given higher priority than the northern part.

The signals detected by the Chinese ship were in the southern section, Houston said.