MH370 search extended as no trace of jet found in target area

US navy's robotic submarine scours Indian Ocean seabed off Western Australia for missing aircraft's black box

A robotic submarine scanning the floor of the Indian Ocean off Western Australia for the missing Malaysia Airlines jet is to begin searching outside the original designated area, where it has failed to find any trace of flight MH370.

The US navy's Bluefin 21 has been creating a three-dimensional sonar map of the ocean floor for more than two weeks, near to where signals that are consistent with an aeroplane’s black box were heard on 8 April.

The search area is a circle with a radius of 10km, at a depth of 4.5km.

The submarine was expected to complete the underwater search area and continue examining adjacent areas, the search co-ordinator said in a statement. The submarine spends four hours travelling to and from the seabed, and 16 hours searching. It takes another four hours for the data collected in each search to be returned for analysis.

Last week, the Australian defence minister, David Johnston, said that an announcement was likely this week on the next phase of the search. The aircraft vanished, with 239 passengers and crew on board, on 8 March on a flight from Kuala Lumpur to Beijing.

Johnston said the next phase was likely to involve more powerful side-scan sonar equipment.

A daily air search for debris north-west of Perth was suspended on Sunday because of bad weather, the search centre said.