Its last communication on the network was made along one of two arcs stretching north-west into Central Asia and southwest into the southern Indian Ocean.

In early April, an effort to find the signals emitted from underwater locator beacons (ULBs) attached to the aircraft's flight recorders, which have a 30- to 40-day battery life, was made.

Malaysian military radar continued to track the aircraft as it turned left, crossed the Malay Peninsula near the Malaysia–Thailand border, and travelled over the Andaman Sea.

Thereafter, the aircraft's satellite data unit (SDU) replied to five hourly, automated status requests between 03:41 and 08:10, and two unanswered ground-to-aircraft telephone calls.

[29] On 15 March, Malaysian Prime Minister Najib Razak announced that Flight 370 had remained in contact with a satellite communication network for several hours after it disappeared and that the aircraft was last located by military radar over the Andaman Sea.

[30] The northern corridor was soon discounted and a search of a remote region of the southern Indian Ocean, led by Australia, began on 18 March.

[31] On 24 March, Malaysia Airlines and Najib announced that the flight had ended in the Southern Indian Ocean without survivors.

[32] Malaysia Airlines confirms that flight MH370 has lost contact with Subang Air Traffic Control at 2.40am, today (8 March 2014).

Using a type of analysis never before used in an investigation of this sort...Inmarsat and the AAIB have concluded that MH370 flew along the southern corridor, and that its last position was in the middle of the Indian Ocean, west of Perth.

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 of 30–40 days.

[72][73] In early April, Malaysia submits a preliminary report to the ICAO, which is publicly released on 1 May along with recordings of conversations between Flight 370 and air traffic control.

[75] During this time, preparations are made for the next phase of the search, which was initially scheduled to begin in August,[103] but did not commence until early October.

[8] On 8 October, the ATSB releases a report on the latest analysis of satellite communications, determining that the most likely location of the aircraft is south of the priority area identified in June.

On 17 January 2017 the underwater search for Flight 370 is suspended after a survey of 120,000 km2 (46,000 sq mi) of the Indian Ocean is unsuccessful in locating the plane.