Advanced sonar joins MH370 hunt

The search for Malaysia Airlines Flight MH370 enters a new underwater phase this week with two specialist ships joining to locate the jetliner almost seven months after it disappeared.

Flight MH370 went missing en route from Kuala Lumpur to Beijing on March 8 with 239 people onboard. No trace of the Boeing 777-200 has been found despite a massive air, sea and underwater search.

Authorities have since used technical data to focus the search in the southern Indian Ocean to the west of Western Australia, along a thin, long arc from which the plane emitted its last satellite "handshake".