The Australian Defense Vessel Ocean Shield, which is searching for transmissions from MH370's flight recorders, has been called off given the likelihood that the flight recorder's batteries may have expired. UPI/Bradley Darvill/Australian Defense Force | License Photo
KUALA LUMPUR, Malaysia, April 15 (UPI) -- The search for Malaysia Airlines MH370 had another setback when a robotic submarine aborted its search of the ocean floor after reaching its depth limit.
The Bluefin-21 was sent on a 16-hour mission to search the Indian Ocean bed for the missing jetliner. However, after six hours the submersible had reached its maximum depth of 15,000 feet, and safety measures on the Bluefin-21 returned it to the surface, according to Australia's Joint Agency Coordination Centre.
The U.S. Navy said in a statement that the six hours of data collected by Bluefin on Monday were analyzed, but nothing of interest was found. Officials said Bluefin would resume search operations Tuesday, once the weather improved.
"To account for inconsistencies with the sea floor, the search profile is being adjusted to extend the sonar search for as long as possible," said an update from the U.S. Navy, which operates the Bluefin-21.
Bluefin is being used in a smaller search area, defined by the four "pings" believed to be consistent with those of a flight recorder detected last week.
Angus Houston, who leads the Joint Agency Coordination Centre, said that Australia's Ocean Shield ship will stop searching for "pings" from the flight recorder, given the strong likelihood that the batteries would have expired by now.
Officials are also investigating an oil slick found Sunday in the vicinity of those four detected pings, and those are the leads investigators have currently.
Flight MH370 from Kuala Lumpur to Beijing, with 239 people aboard, disappeared soon after takeoff on March 8, and has resulted in a massive multinational search effort.
[Joint Agency Coordination Centre]