(Updates JACC comment on smaller search area in fourth paragraph. For more on Flight 370, see EXT3.)
April 17 (Bloomberg) -- An unmanned submarine trolling for the missing Malaysian Air plane completed its first full mission, as investigators sought to narrow the underwater search area after aircraft and ships failed to find any debris.
The Bluefin-21 has searched 90 square kilometers (35 square miles) of ocean floor and data downloaded from its latest trip is being analyzed, Australia’s Joint Agency Coordination Centre said. Technical issues had cut short two earlier sorties. As many as 12 aircraft and 11 ships will continue to comb the Indian Ocean today for signs of debris.
Scouring the Indian Ocean surface northwest of Australia will continue over the Easter weekend, and the underwater search has been “significantly narrowed,” with the use of accoustic analysis creating a more “more focused’ area, the JACC said. At 41 days, the hunt for Flight 370, which disappeared March 8 with 239 people on board, is the longest search for a missing passenger jet in modern aviation history.
‘This represents the best lead we have in relation to missing flight MH370 and where the current underwater search efforts are being pursued to their completion so we can either confirm or discount the area as the final resting place of MH370, JACC said in a release.
The Bluefin-21, which uses side-scan sonar to capture images of the ocean bottom, is pivotal to the search with the batteries in the aircraft’s black boxes now likely dead. The sonar bounces sound waves off the bottom to create images of terrain. It’s supposed to be deployed for 24 hours at a time.
Its first foray was cut short after a built-in safety feature forced it to return to the surface after it dived deeper than its operating limit of 4,500 meters. The second dive was interrupted by a minor battery malfunction, according to Jim Gibson, general manager of Phoenix International Holdings Inc., the company performing the search under contract to the U.S. Navy.
‘‘The search will always continue,” Malaysia’s Acting Transport Minister Hishammuddin Hussein told reporters in Kuala Lumpur today. “It’s just a matter of approach.”
The underwater sonar search of an area close to where pings similar to those from black box emergency beacons were heard will also continue, JACC said.
Data retrieved so far hasn’t revealed any significant objects. The analysis of an oil slick found over the weekend in the current search area also showed the substance didn’t come from an aircraft engine or hydraulic fluid, JACC said.
No audio pulses have been detected since April 8, suggesting the aircraft’s black boxes have run out of battery power. The crash-proof recorders are crucial to determining why the Malaysian Airline System Bhd. jet vanished en route to Beijing from Kuala Lumpur, reversing course and flying into some of the world’s most remote ocean waters.
Scouring the ocean surface for debris with planes and ships will be called off in two to three days as the chance of any floating material being recovered has “greatly diminished,” retired Air Chief Marshal Angus Houston, who heads the JACC, said at a press conference in Perth April 14.
--With assistance from David Fickling in Sydney and Chong Pooi Koon and Elffie Chew in Kuala Lumpur.