The autonomous underwater vehicle Bluefin 21, a US Navy probe equipped with side-scan sonar, was deployed last evening from the Australian navy ship Ocean Shield to map the floor of the Indian Ocean for the wreckage of Malaysia Airlines Flight MH370.
The mission was aborted early, sending the drone back to the surface before expected after it encountered water deeper than its operating limits of 4.5 km.
Search officials analysed data from Bluefin-21, and found no objects of interest, the US Navy said today.
"To account for inconsistencies with the sea floor, the search profile is being adjusted to extend the sonar search for as long as possible," the US statement said.
"Bluefin-21 was unable to complete its first search mission after six hours, due to breaching maximum operating depth," it said.
"The data was analysed and no objects of interest were found," the statement said. "The vehicle is in good material and working condition."
The Bluefin-21 was to make a second mission to the remote Indian Ocean seabed when weather conditions permit.
The search for the missing plane could take up to two months as the underwater vehicle takes six times longer to cover the same area as the towed pinger locator, officials said.
"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 US Seventh Fleet, said in a statement.
Finding the black box is crucial to know what happened on March 8 before the Beijing-bound plane with 239 people, including five Indians, an Indo-Canadian and 154 Chinese nationals, mysteriously vanished after taking off from Kuala Lumpur.
