Once again, aircraft head out to a remote area of the southern Indian Ocean to resume the search for the missing Malaysia Airlines jet.

They're joining a search operation around 1500 km west of this military base in Perth, where officials believe Flight MH370 crashed nearly one month ago.

On Thursday eight military planes, nine ships and even a submarine are taking part.

Malaysia's prime minister Najib Razak visited the Australian military base with his Australian counterpart Tony Abbott, meeting search crews before their planes left for the day.

Malaysian authorities have faced heavy criticism for mismanaging the search

. (SOUNDBITE) (English) PRIME MINISTER OF MALAYSIA NAJIB RAZAK SAYING:

"We owe it to the grieving families to give them comfort and closure to this rather tragic event and the world expects us to do our level best and I'm very confident that you will indeed show what we can do together as a group of nations that we want to find answe