The disappearance of Malaysia Airlines Flight 370 on 8 March 2014 led to a multinational search effort in Southeast Asia and the southern Indian Ocean that became the most expensive search in aviation history.
Despite delays, the search of the priority search area was to be completed around May 2015. On 29 July 2015, a piece of marine debris, later confirmed to be a flaperon from Flight 370, was found on Réunion Island.
On 20 December 2016, it was announced that an unsearched area of around , and approximately centred on location , was the most likely impact location for flight MH370. The search was suspended on 17 January 2017. In October 2017, the final drift study believed the most likely impact location to be at around . The search based on these coordinates was resumed in January 2018 by Ocean Infinity, a private company; it ended in June 2018 without success.
Ships and aircraft from Malaysia, China, India, Japan, Australia, New Zealand, South Korea, Vietnam, the United Kingdom, and the United States were involved in the search of the southern Indian Ocean. Satellite imagery was also made available by Tomnod to the general public so they could help with the search through crowdsourcing efforts.
In March 2022, Ocean Infinity CEO Oliver Plunkett announced that the company was ready to seek approval from the Malaysian government for a search as early as the beginning of 2023.
In June 2024, Ocean Infinity submitted a plan to the Malaysian government to continue the search over off the coast of Western Australia, with the cabinet approving the plan in principle under a $70 million 'no find, no fee' arrangement in December 2024. Final approval was granted in March 2025 and Ocean Infinity began their search. In April 2025, the search was once again suspended. On 30 December 2025, Ocean Infinity resumed searching for the missing aircraft, using the Armada 86 05 vessel. On 8 March 2026, Ocean Infinity announced that their search concluded as of 23 January 2026 without any findings.
Disappearance
Malaysia Airlines Flight 370 was a scheduled flight in the early morning hours of 8 March 2014 from Kuala Lumpur, Malaysia to Beijing, China—one of two daily flights operated by Malaysia Airlines from its hub at Kuala Lumpur International Airport (KLIA) to Beijing Capital International Airport. Flight 370 was scheduled to depart at 00:35 local time (MYT; UTC+08:00) and arrive at 06:30 local time (CST; UTC+08:00). At 00:41 MYT, Flight 370 took off with 239 occupants aboard — 2 pilots, 10 cabin crew, and 227 passengers (152 of whom were Chinese citizens). Flight 370 was cleared by air traffic control to proceed on a direct path to waypoint IGARI (), located between Malaysia and Vietnam over the South China Sea (near the boundary with the Gulf of Thailand).
At 01:07 MYT, the aircraft was at flight level 350—approximately above sea level—when the final message using the ACARS protocol was sent from the aircraft. At 01:19 MYT, Lumpur area air traffic control (ATC) initiated a hand-off to Ho Chi Minh area ATC. The Captain responded "Good night Malaysian Three Seven Zero," (originally reported to have been "all right, good night"), after which no further communications were made with the pilots. The crew was expected to contact air traffic control in Ho Chi 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 06:30 local time (same time zone as Malaysia; 22:30 UTC, 7 March). At 07:24, Malaysia Airlines issued a media statement that Flight 370 was missing after contact was lost with Malaysian ATC at 02:40. The time of the last contact with ATC was later corrected to 01:19; Malaysia Airlines was notified at 02:40.
Initial search in Southeast Asia (March 2014)
The watch supervisor at Kuala Lumpur Area Control Centre—which was the air traffic control centre that was last in contact with Flight 370—activated the Kuala Lumpur Aeronautical Rescue Coordination Centre (ARCC) at 05:30, over four hours after communication was lost with Flight 370. When Malaysia Airlines issued a media statement two hours later, they claimed that they were "working with the authorities who have activated their Search and Rescue team to locate the aircraft".
On 9 March, the Chief General of the Royal Malaysian Air Force announced that Malaysia was analysing military radar recordings and that there was a "possibility" that Flight 370 had turned around and travelled over the Andaman Sea. The search radius was increased from the original from its last known position, south of Thổ Chu Island, to , and the area being examined then extended to the Strait of Malacca along the west coast of the Malay Peninsula, with waters both to the east of Malaysia in the Gulf of Thailand, and in the Strait of Malacca along Malaysia's west coast, being searched.
Numerous sightings of possible debris were made, but no debris from Flight 370 was discovered. Offshore oil slicks near Vietnam on 9 and 10 March later tested negative for aviation fuel. Satellite images taken on 9 March and posted on a Chinese website showed three floating objects measuring up to 24 × 22 metres (79 × 72 ft) at , but a search of the area did not find the objects; Vietnamese officials said the area had been "searched thoroughly". By the end of 9 March, 40 aircraft and more than two dozen vessels from several nations were involved in the search.
The Royal Malaysian Air Force confirmed on 10 March that Flight 370 made a "turn back". The following day, China activated the International Charter on Space and Major Disasters to aggregate satellite data to aid the search. On 12 March, Malaysian officials announced that an unidentified aircraft, possibly Flight 370, was last located by military radar at 02:15 in the Andaman Sea, northwest of Penang Island and near the limits of the military radar's coverage. The focus of the search shifted to the Andaman Sea and the Malaysian government requested help from India to search in the area.
International involvement The Malaysian government mobilised its civil aviation department, air force, navy, and Maritime Enforcement Agency; and requested international assistance under Five Power Defence Arrangements provisions and from neighbouring states. Various nations mounted a search and rescue mission in the region's waters. Within two days, the countries had already dispatched more than 34 aircraft and 40 ships to the area.
On 11 March, the China Meteorological Administration activated the International Charter on Space and Major Disasters, a 15-member organization whose purpose is to "provide a unified system of space data acquisition and delivery to those affected by natural or man-made disasters", the first time the charitable and humanitarian redeployment of the assorted corporate, national space agency, and international satellite assets under its aegis had been used to search for an airliner.
Another 11 countries joined the search efforts by 17 March after more assistance was requested by Malaysia. At the peak of the search effort and before the search was moved to the south Indian Ocean, 26 countries were involved in the search, contributing in aggregate nearly 60 ships and 50 aircraft. In addition to the countries already named, these parties included Australia, Bangladesh, Brunei, Cambodia, China, France, India, Indonesia, Japan, Myanmar, New Zealand, Norway, Philippines, Russia, Singapore, South Korea, Taiwan, Thailand, United Arab Emirates, United Kingdom, United States, and Vietnam. While not participating in the search itself, Sri Lanka gave permission for search aircraft to use its airspace. Malaysia deployed military fixed-wing aircraft, helicopters, and ships. A co-ordination centre at the National Disaster Control Centre (NDCC) in Pulau Meranti, Cyberjaya, was established.
On 16 March, three staff members of the French government agency BEA flew to Kuala Lumpur to share with Malaysian authorities their experience in the organisation of undersea searches, acquired during the search for the wreckage of Air France Flight 447. The United Kingdom provided technical assistance and specialist capabilities from the Ministry of Defence, the UK Hydrographic Office, Department for Transport and the Met Office. The Comprehensive Nuclear-Test-Ban Treaty Organization Preparatory Commission analysed information from its network of infrasound detection stations, but failed to find any sounds made by Flight 370.
Satellite communications and radar
On 11 March, New Scientist reported that, prior to the aircraft's disappearance, two reports about the engine status using the Aircraft Communications Addressing and Reporting System (ACARS) protocol had been automatically sent to engine manufacturer Rolls-Royce's monitoring centre in the United Kingdom.
On 12 March, it was reported that military radar indicated the aircraft turned west away from the intended flight path and continued flying for 70 minutes before disappearing from Malaysian radar near Pulau Perak. It was also reported that it had been tracked flying at a lower altitude across Malaysia to the Malacca Strait, approximately from its last contact with civilian radar. The next day, the Royal Malaysian Air Force chief denied the report. A few hours later, however, the Vietnamese transport minister claimed that Malaysia had been informed on 8 March by Vietnamese air traffic control personnel, that they had "noticed the flight turned back west". A US radar expert analysing the radar data reported that they did indeed indicate that the aircraft had headed west across the Malay Peninsula. The New York Times reported that the aircraft experienced significant changes in altitude.
On 13 March, The Wall Street Journal, citing sources in the US government, asserted that Rolls-Royce had received an aircraft health report every thirty minutes for five hours, implying that the aircraft had remained aloft for four hours after its transponder went offline; Malaysia denied the report. The Wall Street Journal later amended its report and stated simply that the belief of continued flight was "based on analysis of signals sent by the Boeing 777's satellite-communication link... the link operated in a kind of standby mode and sought to establish contact with a satellite or satellites. These transmissions did not include data." The following day, satellite operator Inmarsat released a public statement stating that "routine, automated signals were registered" on its network; analysis of these "keep-alive message[s]" that continued to be sent after air traffic control first lost contact could help pinpoint the aircraft's location.
At a press conference on 15 March, Malaysian Prime Minister Najib Razak confirmed that satellite communications from Flight 370 continued for several hours after contact with it was lost over the South China Sea and that the last signal—received at 08:11 Malaysian time—might have originated from as far north as Kazakhstan. Najib explained that the signals could not be more precisely located than to one of two possible loci: a northern locus stretching approximately from the border of Kazakhstan and Turkmenistan to northern Thailand, or a southern locus stretching from Indonesia to the southern Indian Ocean. Many of the countries on a possible northerly flight route—China, Thailand, Kazakhstan, Pakistan, and India—denied the aircraft could have entered their country's airspace, because military radar would have detected it. Inmarsat had provided an initial analysis of the signals from Flight 370, which produced the two loci, on 11 March.