Missing Jet's Black Box Batteries May Be Dead, Experts Say

The missing Malaysia Airlines Flight 370's black box batteries may be dead as the extensive search effort for the jet enters its sixth week in the Indian Ocean

Last week, officials were encouraged to continue searching by a series of underwater pings from the black box. However, those signals have ceased.

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On Thursday, a fifth signal was detected by an Australian Air Force P-3 Orion. The P-3 Orion had been dropping sonar buoys into the water near where a U.S. Navy device picked up four sounds. The signal was said to be emanating from a man-made device deep in the Indian Ocean.

Despite that there were no new transmissions from the black boxes' locator beacons, air and sea crews continued their search in the southern Indian Ocean on Monday in the hopes of finding debris or other sounds from the plane, The Associated Press reported.

"We're now into Day 37 of this tragedy," aviation expert Geoffrey Thomas told reporters. "The battery life on the beacons is supposed to last 30 days. We're hoping it might last 40 days. However, it's been four or five days since the last strong pings. What they're hoping for is to get one more, maybe two more pings so they can do a triangulation of the sounds and try and narrow the (search) area."

In the next phase of the search, the Australian Navy will use a robotic submarine drone that will descend as far as 15,000 feet into the sea, where it will use sonar to create a three-dimensional map of the sea floor to locate the wreckage.

The underwater drone, a Bluefin 21 autonomous sub, will be launched Monday evening by the Australian navy's Ocean Shield ship, according to Angus Houston, the head of a joint agency coordinating the search off Australia's west coast.

As of Sunday, there are 14 ships and 10 airplanes involved in the search, ABC News reported.

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Malaysia Airlines Flight 370 had 239 people aboard when it went missing on March 8, 227 of who were passengers and 12 of who were crew members.

Of the 227 passengers, three were Americans, and two of them were reportedly children. Others aboard the plane included 38 Malaysians, seven Indonesians, six Australians, five Indians, and four French people. The remainder of the passengers on the flight were Chinese nationals.