A U.S. Navy P8 Poseidon leaves Perth International Airport to begin another day searching for the Malaysia airliner jet, which went missing on March 8th.

There have been around 133 missions like this one, hunting for debris from Flight MH370 in a remote area of the southern Indian Ocean.

Not a single piece of wreckage has yet been found. But officials have concluded - based on satellite data - that it ended its flight in the sea, 1,500 kilometres west of Perth.

A massive international operation -- in both air and sea -- is hunting for answers about what happened to the jet and the 239 people on board.

Here video shows a U.S. Navy "towed pinger locator" onboard an Australian ship picking up possible transmissions from the black box recorders...but no further signals have been traced since the weekend.

Coordinator, Air Chief Marshal Angus Houston, said the search had to be narrowed before an underwater vehicle could look for wreckage on the sea floor.