Ocean surveillance remains big challenge

Australia has a vast problem watching over 14 million square kilometres of ocean for the occasional interloper, be it a people or drug smuggler, fishing poacher or terrorist.

This involves a complex network of satellites and radar, RAAF surveillance aircraft and Navy and Australian Border Force vessels.

But that will soon be enhanced with new RAAF P-8A Poseidon maritime surveillance aircraft replacing ageing Orions, and Triton unmanned aircraft which can stay aloft for more than 24 hours.

A new Australian Strategic Policy Institute study says Australia could go a step further and use unmanned maritime vessels, small relatively low-coast boats able to keep watch over their little bit of ocean for months on end.

Current models now being trialled overseas can operate without human intervention, taking power from wind or sun and only reporting in when they spot something of interest. Then an aircraft or patrol boat could be dispatched to investigate.

ASPI says some current models can operate for as little as $50 an hour, a bargain compared with Triton's $19,325 per hour operating cost and $120 million capital cost. However, Triton can cover vastly more ocean.

The study says UMVs could form a wide net of passive surveillance across large areas of ocean.

"Most potential maritime threats to Australia emanate from our northern waters, so an array of persistent, roughly equidistant UMVs along our northern approaches could act as a line of first detection against incursions," it said.

ASPI said current UMVs offered clear capability benefits for Australia but emerging technology could make them even better.