MH370 hunt to resume

Ocean Shield leaves HMAS Stirling today to resume search for MH370. Picture: Paul Kane/Getty Images

The Australian Defence vessel Ocean Shield will depart today morning for the search area for Malaysia Airlines flight MH370, which disappeared on March 8 with 239 passengers and crew.

The ship has spent four days at Stirling naval base being resupplied and is expected to resume the search early next week.

International teams looking for MH370 are still confident it will be found in the current search area.

The upbeat assessment from Joint Agency Co-ordination Centre head Air Chief Marshal Angus Houston comes as investigators assess all the scientific data.

According to Air Chief Marshal Houston, "there may need to be a fine adjustment to the search area that's been defined".

Speaking on ABC radio this week, he said organising the next phase using towed sonar vehicles that can scan down to 6000m could take four to six weeks.

"There's only a handful of them in the world," he said.

As crews prepared to widen the underwater search area and map the deep ocean floor, Air Chief Marshal Houston warned it would be very challenging.

"You could get lucky, you could find it right at the beginning of the search," he said, but added it was more likely to take a "long time".

He said the data audit was necessary and "sensible" to ensure there has been "no oversights, no flaws in the logic". However, he was convinced the search team was looking in the right area.

Asked on ABC Radio if he would commit to continue leading the co-ordination effort over the next eight to 12 months, Air Chief Marshal Houston said he would keep going as long as he was required to.

The search area is 700km by 80km and the zone of particular interest is at the northern end.

So far, a Bluefin-21 autonomous underwater vehicle has searched an area of 10km radius around the second ping from MH370's black box that was held for 13 minutes.

The area around the first ping, which is 10km further north and which was held for two hours, is yet to be fully investigated.

The sea bed to the north of ping one drops off significantly to 5500m - well beyond the capability of the Bluefin-21.

With agencies