Search for Malaysia Airlines Flight 370 Minh City as the aircraft passed into Vietnamese airspace just north of the point where the final verbal communication was made. Less than two minutes later, at 01:21, the aircraft disappeared from the radar screens of both Malaysian and Vietnamese ATC, which use secondary radar to track aircraft. No distress call was made. Flight 370 was expected to arrive in Beijing at 6:30 local time (same time zone as Malaysia; 22:30 UTC, 7 March). At 7:24, Malaysia Airlines issued a media statement that Flight 370 was missing after contact was lost with Malaysian ATC at 2:40. The time of the
Timeline of Malaysia Airlines Flight 370 soon discounted and a search of a remote region of the southern Indian Ocean, led by Australia, began on 18 March. On 24 March, Malaysia Airlines and Najib announced that the flight had ended in the Southern Indian Ocean without survivors. In early April, an intense effort—the "acoustic search"— was made to detect the acoustic signals generated by underwater locator beacons (ULBs, also known as "pingers") attached to the flight recorders on Flight 370. After immersion in water, the ULBs emit an acoustic signal (also called a "ping") at a specific frequency once per second and have a battery life