With time running out to find the flight recorder of missing Malaysia Airlines flight MH370 Saturday's search was the most intensive so far.<br /> <br />The Australian navy vessel Ocean Shield has joined the hunt.<br /> <br />It's being used to tow specialist sonar equipment that could trace locator signals from the plane's black box flight recorder.<br /> <br />The ship's on a converging 240-kilometre course with a British vessel in the southern Indian Ocean.<br /> <br />Royal Australian Navy Commander James Lybrand says they're hoping for a result.<br /> <br />(SOUNDBITE)(English) ROYAL AUSTRALIAN NAVY COMMANDER JAMES LYBRAND SAYING:<br /> <br />"On board the Ocean Shield at the moment we're certainly doing all we can in the location we're at. We're running a series of parallel legs over best constructed location of MH370's last position."<br /> <br />Also taking part are 10 military aircraft, three civilian ones, and 11 ships.<br /> <br />A British nuclear submarine and a Malaysian frigate were also due to join the search.