A U.S. Navy underwater drone sent to search for a missing Malaysian jetliner on the floor of the Indian Ocean could take up to two months to scour a 230-square-mile area where the plane is believed to have sunk, U.S. search authorities said Tuesday.The prediction coincided with the end to the abbreviated first mission by the Bluefin-21 autonomous underwater vehicle six hours into what was meant to be a 16-hour operation Monday after it exceeded its 14,750-feet depth limit and was automatically returned to the surface.
But having not heard a "ping" for almost a week and with the batteries on the locator beacons two weeks past their 30-day expected life, the slow-moving "autonomous underwater vehicle" was launched Monday to try and locate wreckage."The AUV takes six times longer to cover the same area as the towed pinger locator. It is estimated that it will take the AUV anywhere from six weeks to two months to scan the entire search area," Lt. J.G. Daniel S. Marciniak, a spokesman for the U.S. Seventh Fleet, said in a statement.
From its aborted first mission, the Bluefin-21 produced six hours of data which authorities analyzed to find no objects of interest, Marciniak added. The drone was expected to embark on its second search mission late on Tuesday.The robot, which takes two hours to descend another two to return to the surface, as well as several hours to download data, will build up a detailed acoustic image of the area using sophisticated "sidescan" sonar. It hopes to repeat its success in finding a F-15 fighter jet which crashed off Japan last year.
It is capable of spending up to 16 hours scouring the sea floor. If it detects possible wreckage, it will be sent back to photograph it in underwater conditions with extremely low light.Officials are focusing their acoustic search on an area equivalent to a medium-sized city--230 square miles. But the much broader search area off the Australian coast covers about 60,000 sq km, according to the government.
The deep sea area now being searched, the Zenith Plateau, has never been mapped in detail because it is not in any country's economic zone.However the sea floor is likely covered in "foraminiferal ooze," a sludge formed by microscopic marine organisms, which would show up any large metallic object clearly, James Cook University marine geologist Robin Beaman told Reuters.
"A sidescan is very good at detecting the difference in the acoustic return of a hard object versus a soft, muddy sea floor," he said. "This is quite a good environment for looking for wreck debris, albeit deep."The Bluefin's main challenge was to remain within 165 feet of the seabed to ensure the best quality sidescan detection without exceeding its 4.5 km depth limit which could risk damaging it, Beaman said.
Malaysian authorities have still not ruled out mechanical problems as causing the plane's disappearance, but say evidence suggests it was deliberately diverted from its scheduled route from Kuala Lumpur to Beijing.An aircraft's black box records data from the cockpit and conversations among flight crew and may provide answers about what happened to the missing plane.
The search for the missing plane is on track to be the most difficult and expensive search and recovery operation in aviation history.Reuters