Hollywood director James Cameron has offered up his deep-sea diving expertise in the ongoing search for missing Malaysia Airlines flight Mh370.

The search for the missing jet, which disappeared last month (Mar14) with 239 onboard, is soon to go underwater with the launch of a mini-submarine which will scan the bed of the Indian Ocean for wreckage, and Cameron has now offered up his advice.

The Titanic moviemaker, who is an avid devotee of deep-sea diving, insists the success of the search will hinge on whether the 'ping' signals picked up by the search teams were actually emitted from the plane's black box recording device, but he is adamant he knows exactly how to find the missing plane.

In a chat with fans on Reddit.com, Cameron explains, "Well, I know how it will be done. If these pings that they're receiving are confirmed as being from the flight recorders, then they'll triangulate the acoustic data that they have so far, and they'll generate what's called a search box. I don't know how big that will be, but it might be 25-30 miles on a side, it might be a very large piece of ocean... The next step would be to use an Auv, an autonomous underwater vehicle, and have it run at 400 or 500 feet above the bottom and do a sonar profile of the bottom... Then you analyse any signatures... that don't look like flat bottom, and you say 'Are those rocks, is that geology or does that look like the piece of an aircraft?' And then once you have those targets... you go back, either with that type of vehicle or an Rov (a remotely operated vehicle) that would be hanging down from a ship on a cable. And you'd take a look essentially with a video camera. And then you'd be able to identify whether that target was in fact the aircraft you are looking for."

He then adds, "That's how it would be done. But it all hinges on whether or not those pings are actually from the black box, and not from something else, like a scientific instrument that's drifted off course or whatever."

Cameron used his deep-sea diving expertise on his films The Abyss and Titanic, and he broke the record for the deepest ever solo submarine dive in 2012 when he plunged seven miles (11 kilometres) underwater to the Mariana Trench of the Pacific Ocean.