Europe's aviation watchdog has announced new proposals to make it easier to find flight recorders, known as black boxes, from missing planes. The plans include extending the transmission time of underwater locating devices fitted on the black boxes from 30 to 90 days. The move comes in response to the disappearance of Malaysia Airlines flight MH370 on 8 March. The plane vanished en route to Beijing, with 239 people on board. The aircraft lost contact with air traffic controllers over the South China Sea, some seven hours after it took off from Kuala Lumpur. Officials now believe, based on satellite data, that it ended its journey in the sea far west of the Australian city of Perth. It is not yet known what caused the plane to fly so far off course. Finding its "black box" flight recorders is seen as key to understanding what happened. As part of the measures, the European Aviation Safety Agency (EASA) said large aeroplanes flying over oceans should be equipped with a new pinger frequency, making it easier to locate the recording devices under water. In addition, the minimum recording duration of cockpit voice recorders installed on new planes should be increased from two to 20 hours. "The tragic flight of Malaysia Airlines MH370 demonstrates that safety can never be taken for granted," EASA director Patrick Ky said in a statement on Tuesday. "The proposed changes are expected to increase safety by facilitating the recovery of information by safety investigation authorities." So far, an intensive search operation has found no sign of flight MH370. Officials from Australia, Malaysia and China are meeting in the Australian capital, Canberra, this week to discuss the next stage in the operation. Australian Deputy Prime Minister Warren Truss said new sonar and submersible equipment would be needed to scour a large area of ocean floor. An initial search of the area where acoustic signals thought to be from flight recorders were heard found nothing. On Wednesday, experts are due to share all the information, including satellite data, collected to date, at the talks in Canberra. Australia has warned that the next stage of the search could take up to a year.