Australia's Joint Agency Coordination Center has provided an update on the search efforts for flight MH370. In a press briefing, retired air chief Marshal Angus Houston said an underwater search is being conducted to look for signals from the black box.

The black box contains a locator beacon which sends out a signal that can be picked up by search equipment. The beacon is designed with a battery life of about 30 days. A total of 14 aircraft and 9 ships are taking part in Friday's search. The search area has been refined to 217,000 square kilometers of the southern Indian Ocean, northwest of Perth. A total of 26 State Emergency Service volunteers from Australia are working as air observers on three new civil aircraft.

A Chinese aircraft took off from Perth International Airport early Friday morning to spearhead the search. Meanwhile, two Chinese ships have been searching an area where debris were spotted by satellite on Wednesday. So far, none of the floating debris found have been from the plane.