Film director and deep-sea explorer James Cameron said robot probes that were used on the wreck of the Titanic could be deployed to investigate debris from the missing Malaysian jet if it can be located on the ocean floor.
A U.K. warship with advanced undersea listening tools reached the area of the Indian Ocean where a Chinese vessel picked up two signals that may be from black boxes of the Malaysian jet that vanished a month ago.
The U.S. joined Australia in scouring an area in the southern Indian Ocean about 1 1/2 times the size of California for missing Malaysian Air Flight 370, as the disappearance became the longest in modern airline history.
As the search for a Boeing aircraft carrying 239 people risks becoming the longest hunt in modern civil aviation, Malaysia broadened its appeal for international help while the area being combed through grows larger every day.
Teams trying to locate the Boeing Co. 777 that vanished over the sea three days ago will scour data for radar signatures while seeking to detect pinging from black boxes as the search for visible wreckage proves elusive.