A robotic submarine searching for signs of the missing Malaysia Airlines jet managed to complete a "full mission" Thursday for first time since it was deployed earlier this week.
The U.S. Navy-owned Bluefin-21 has searched approximately 35 square miles to date, and data it has collected from its latest mission is being analyzed, Australia’s Joint Agency Coordination Center said in a statement.
A “technical issue” was blamed for Bluefin-21's premature return from the deep off Australia's west coast on Tuesday, while on Monday a safety feature kicked in as the vessel exceeded its "operation depth limit" of 14,763 feet, or about 2.8 mile and it returned to the surface after six hours.
Bluefin-21 can create a three-dimensional sonar map of the area to chart any debris on the sea floor. Authorities said data downloaded and analyzed from Bluefin-21's initial search on Wednesday highlighted “no significant detections.”
The total search area the Bluefin-21 could eventually cover — if nothing is found sooner - is around 230 square miles. Officials said it could take months to scan and map the entire zone.
Meanwhile, preliminary analysis of oil spotted on the surface of the sea on Monday has confirmed that it is not aircraft engine oil or hydraulic fluid.
A visual search for debris on the ocean surface also continues over more than 15,000 square miles of water about 1,400 miles northwest of Perth, with 12 planes and 11 ships scouring the southern Indian Ocean.
The Associated Press contributed to this report.