Sub hunting for source of 'pings' in Malaysian plane search

Perth, Australia: Search crews were for the first time sending a sub deep into the Indian Ocean to try and determine whether faint sounds detected by equipment on board an Australian ship are from the missing Malaysia Airlines plane's black boxes, Australia's acting prime minister said Tuesday. (Possible signals from lost Malaysia Airlines jet's black boxes heard)

Warren Truss, Australia's acting prime minister while Tony Abbott is overseas, said the crew on board the Ocean Shield will launch the underwater vehicle, the Bluefin 21 autonomous sub, on Tuesday. The sub can create a sonar map of the area to chart any debris on the sea floor. If it maps out a debris field, the crew will replace the sonar system with a camera unit to photograph any wreckage. (Sub hunting for source of 'pings' in Malaysian plane search)

Angus Houston, who is heading the search, said Monday that the Ocean Shield, which is towing sophisticated U.S. Navy listening equipment, detected late Saturday and early Sunday two distinct, long-lasting sounds underwater that are consistent with the pings from an aircraft's "black boxes" - the flight data and cockpit voice recorders.(Search for missing Malaysia plane set to move to sea floor)

Crews have been trying to re-locate the sounds since then to determine whether they are from Flight 370, but so far had no luck, Truss said.

"Today is another critical day as we try and reconnect with the signals that perhaps have been emanating from the black box flight recorder of the MH370," he said. "The connections two days ago were obviously a time of great hope that there had been a significant breakthrough and it was disappointing that we were unable to repeat that experience yesterday."

Truss said the crew would use the sub today to examine the water in the search area in the hopes of another breakthrough.