Malaysia Airlines Flight 370

== Speculated causes of disappearance ==
{{Main|Malaysia Airlines Flight 370 disappearance theories}}

=== Murder/suicide by pilot ===
Malaysian police searched the homes of the pilots and seized financial records for all 12 crew members. The preliminary report issued by Malaysia in March 2015 stated that there was "no evidence of recent or imminent significant financial transactions carried out" by any of the pilots or crew, and that analysis of the behaviour of the pilots on CCTV showed "no significant behavioural changes".<ref name="Interim report-March 2015" />{{Rp|20, 21}}

However, US officials believe the most likely explanation to be that someone in the cockpit of Flight 370 re-programmed the aircraft's autopilot to travel south across the Indian Ocean.<ref name="AutoVQ-45"/><ref>{{cite web|url=http://www.news.com.au/travel/travel-updates/mh370-deputy-pm-warren-truss-announces-underwater-search-for-missing-malaysia-airlines-plane-will-begin-in-august/story-fnizu68q-1226967783002|title=Deputy PM Warren Truss announces underwater search for missing plane will begin in August|website=NewsComAu|access-date=28 September 2014|archive-date=27 June 2014|archive-url=https://web.archive.org/web/20140627001802/http://www.news.com.au/travel/travel-updates/mh370-deputy-pm-warren-truss-announces-underwater-search-for-missing-malaysia-airlines-plane-will-begin-in-august/story-fnizu68q-1226967783002|url-status=dead}}</ref> Media reports claimed that Malaysian police had identified Captain Zaharie as the prime suspect, if human intervention were eventually proven to be the cause of Flight 370's disappearance.<ref name="Australian-pilot behaviour">{{cite web|last1=Sheridan|first1=Michael|title=Suspicion falls again on Malaysia Airlines flight 370's captain Zaharie Shah|url=http://www.theaustralian.com.au/business/aviation/suspicion-falls-again-on-malaysia-airlines-flight-370s-captain-zaharie-shah/story-e6frg95x-1226962734150|website=The Australian|access-date=3 July 2014|date=22 June 2014|archive-date=5 July 2014|archive-url=https://web.archive.org/web/20140705053302/http://www.theaustralian.com.au/business/aviation/suspicion-falls-again-on-malaysia-airlines-flight-370s-captain-zaharie-shah/story-e6frg95x-1226962734150|url-status=live}}</ref><ref>{{cite web|last1=Sheridan|first1=Michael|title=MH370 pilot 'chief suspect'|url=http://www.thesundaytimes.co.uk/sto/news/world_news/Asia/article1425492.ece|archive-url=https://web.archive.org/web/20140622143549/http://www.thesundaytimes.co.uk/sto/news/world_news/Asia/article1425492.ece|url-status=dead|archive-date=22 June 2014|website=The Sunday Times|access-date=3 July 2014|date=22 June 2014}}</ref><ref name="Pilot behaviour">{{cite web|title=Malaysian police investigation names MH370 pilot 'prime suspect'|url=http://www.news.com.au/travel/travel-updates/malaysian-police-investigation-names-mh370-pilot-prime-suspect/story-fnizu68q-1226962811653|publisher=[[News Corp Australia]]|website=[[News.com.au]]|first1=Jenni|last1=Ryall|author2=Staff writers|name-list-style=amp|access-date=3 July 2014|date=23 June 2014|archive-date=2 July 2014|archive-url=https://web.archive.org/web/20140702153926/http://www.news.com.au/travel/travel-updates/malaysian-police-investigation-names-mh370-pilot-prime-suspect/story-fnizu68q-1226962811653|url-status=dead}}</ref><!-- Note: Articles discussing the flight simulator revelation all reference the The Sunday Times article, which is behind a pay wall. The ST article is listed as a reference, but the editor who added it was unable to verify that article's claims, only assuming that other new source's claims citing that article are accurate. The "Australian (newspaper)" article lists "Michael Sheridan" (author of TST article) and "The Times" at top and may be identical to the ST article. --> In 2020, [[Tony Abbott]], the Prime Minister of Australia when MH370 disappeared, disclosed in a Sky News documentary: "My very clear understanding, from the very top levels of the Malaysian government, is that from very, very early on, they thought it was murder-suicide by the pilot."<ref>{{Cite web |last=Lavalette |first=Tristan |date=19 February 2020 |title=Abbott says top Malaysian leaders suspected pilot of MH370 |url=https://apnews.com/general-news-3feb92bc2b2105c4bce97d06316e9e8c |url-status=live |archive-url=https://web.archive.org/web/20231225082433/https://apnews.com/general-news-3feb92bc2b2105c4bce97d06316e9e8c |archive-date=25 December 2023 |access-date= |website=AP News}}</ref>

The murder/suicide theory is consistent with the suggestion, by retired British aviation engineer Richard Godfrey, that the flight path of the aircraft could be plotted by analysis of the disruption to [[WSPR (amateur radio software)|Weak Signal Propagation Reporter]] (WSPR) signals on the day in question. It was reported, in March 2024, that scientists at the [[University of Liverpool]] were undertaking a major new study to verify how viable the technology is, and what this could mean for locating the aircraft.<ref>{{cite web |title=Why Planes Vanish: The Hunt for MH370 |url=https://www.bbc.co.uk/iplayer/episode/m001x0yh/why-planes-vanish-the-hunt-for-mh370 |publisher=BBC iPlayer |date=6 March 2024 |access-date=7 March 2024 |archive-date=6 March 2024 |archive-url=https://web.archive.org/web/20240306110244/https://www.bbc.co.uk/iplayer/episode/m001x0yh/why-planes-vanish-the-hunt-for-mh370 |url-status=live }}</ref> However the creator of WSPR, Nobel Prize laureate [[Joseph Hooton Taylor Jr.]], has stated: "I do not believe that historical data from the WSPR network can provide any information useful for aircraft tracking". Specifically relating to MH370, Taylor stated: "It's crazy to think that historical WSPR data could be used to track the course of ill-fated flight MH370. Or, for that matter, any other aircraft flight".<ref>{{cite web |title=WSPR Can't Find MH370 |url=https://mh370.radiantphysics.com/2021/12/19/wspr-cant-find-mh370/ |date=19 December 2021 |access-date=23 March 2024 |archive-date=17 March 2024 |archive-url=https://web.archive.org/web/20240317052641/https://mh370.radiantphysics.com/2021/12/19/wspr-cant-find-mh370/ |url-status=live }}</ref>

==== Pilot's flight simulator ====
In 2016, [[New York (magazine)|''New York'']] magazine wrote that a confidential document from the Malaysian police investigation showed an [[FBI|FBI analysis]] of the flight simulator's computer hard drive found a route on Captain Zaharie's home flight simulator that closely matched the projected flight over the Indian Ocean and that this evidence had been withheld from the publicly released investigative report.<ref>{{cite web|last1=Wise|first1=Jeff|title=Exclusive: MH370 Pilot Flew a Suicide Route on His Home Simulator Closely Matching Final Flight|url=https://nymag.com/daily/intelligencer/2016/07/mh370-pilot-flew-suicide-route-on-home-simulator.html|website=New York Magazine|publisher=New York Media|date=22 July 2016|access-date=22 July 2016|archive-date=23 July 2016|archive-url=https://web.archive.org/web/20160723005940/http://nymag.com/daily/intelligencer/2016/07/mh370-pilot-flew-suicide-route-on-home-simulator.html|url-status=live}}</ref> ''New York'' wrote as follows:
{{cquote|''New York'' has obtained a confidential document from the Malaysian police investigation into the disappearance of Malaysia Airlines Flight 370 that shows that the plane's captain, Zaharie Ahmad Shah, conducted a simulated flight deep into the remote southern Indian Ocean less than a month before the plane vanished under uncannily similar circumstances. The revelation, which Malaysia withheld from a lengthy public report on the investigation, is the strongest evidence yet that Zaharie made off with the plane in a [[Suicide by pilot|premeditated act of mass murder-suicide]].<p> [...] The newly unveiled documents [...] suggest Malaysian officials have suppressed at least one key piece of incriminating information. This is not entirely surprising: There is a history in aircraft investigations of national safety boards refusing to believe that their pilots could have intentionally crashed an aircraft full of passengers.</p>}}

The FBI's findings about the flight simulation were confirmed by the ATSB.<ref>{{cite web|title=MH370 pilot's flight simulator plotted course over southern Indian Ocean|url=https://www.theguardian.com/world/2016/jul/28/mh370-pilot-flight-simulator-plot-course-southern-indian-ocean|last=Hunt|first=Elle|work=The Guardian|location=Sydney|date=28 July 2016|access-date=28 July 2016|url-access=registration|archive-date=28 July 2016|archive-url=https://web.archive.org/web/20160728123158/https://www.theguardian.com/world/2016/jul/28/mh370-pilot-flight-simulator-plot-course-southern-indian-ocean|url-status=live}}</ref> News of the simulation was also confirmed by the Malaysian government,<ref>{{cite news |url=https://www.cbsnews.com/news/malaysia-confirms-flight-370-pilot-plotted-fatal-route/ |website=CBS News |title=Malaysia confirms Flight 370 pilot plotted fatal route |date=5 August 2016 |access-date=15 May 2018 |archive-date=15 May 2018 |archive-url=https://web.archive.org/web/20180515044258/https://www.cbsnews.com/news/malaysia-confirms-flight-370-pilot-plotted-fatal-route/ |url-status=live }}</ref> but reported as "nothing sinister".<ref name="ABCus_2014-04-02"/><ref name="BBC_2014-03-29"/>

==== Power interruption ====
The SATCOM link functioned normally from pre-flight (beginning at 00:00 MYT<!-- exactly -->) until it responded to a ground-to-air ACARS message with an acknowledge message at 01:07. At some time between 01:07 and 02:03, power was lost to the Satellite Data Unit (SDU). The final report stated "it is likely that the loss of communication prior to the diversion is due to the systems being manually turned off or power interrupted to them." Malaysian Prime Minister, Najib Razak, said it was clear that the radar transponders and the flight data transmission system were turned off deliberately by someone trying to hide the plane's position and heading.<ref>{{Cite web |last=Marks |first=Paul |date=15 March 2014 |title=Data transmission system on MH370 deliberately disabled |url=https://www.newscientist.com/article/dn25232-data-transmission-system-on-mh370-deliberately-disabled/ |url-status=live |archive-url=https://web.archive.org/web/20240115072035/https://www.newscientist.com/article/dn25232-data-transmission-system-on-mh370-deliberately-disabled/ |archive-date=15 January 2024 |access-date= |website=New Scientist}}</ref> At 02:25, the aircraft's SDU rebooted itself and sent a log-on request.<ref name=ATSB />{{rp|22}}<ref name="Ground log" />{{Rp|36–39}}

=== Passenger involvement ===
United States and Malaysian officials reviewed the backgrounds of every passenger named on the manifest.<ref name="20140309washingtonpost">{{cite news |author1=Denyer |first=Simon |author2=Barnes |first2=Robert |last3=Harlan |first3=Chico |name-list-style=amp |date=9 March 2014 |title=Debris spotted may be from missing Malaysian Airline flight |url=https://www.washingtonpost.com/world/four-flew-with-false-id-aboard-malaysia-airlines-plane-that-vanished-over-south-china-sea/2014/03/09/4b0d8a8c-a763-11e3-b61e-8051b8b52d06_story.html |url-status=dead |archive-url=https://web.archive.org/web/20140309183226/https://www.washingtonpost.com/world/four-flew-with-false-id-aboard-malaysia-airlines-plane-that-vanished-over-south-china-sea/2014/03/09/4b0d8a8c-a763-11e3-b61e-8051b8b52d06_story.html |archive-date=9 March 2014 |newspaper=[[The Washington Post]]}}</ref> One passenger, who worked as a flight engineer for a Swiss jet [[Air charter|charter company]], was briefly under suspicion as a potential hijacker because he was thought to have the relevant "aviation skills".<ref name="20140317straitstimes"/>

Two men were found to have boarded Flight&nbsp;370 with stolen passports, which raised suspicion in the immediate aftermath<!-- within 36 hours --> of its disappearance.<ref name="20140309nytimes"/><ref name="cnn14"/> The passports, one Austrian and one Italian, had been reported stolen in Thailand within the preceding two years.<ref name="20140309nytimes"/> The two passengers were later identified as Iranian men, one aged 19 and the other 29, who had entered Malaysia on 28&nbsp;February using valid Iranian passports. They were believed to be [[asylum seekers]],<ref name="AutoVQ-41"/><ref name="AutoVQ-42"/> and the [[Secretary General of Interpol]] later stated that the organisation was "inclined to conclude that it was not a terrorist incident".<ref name="BBC_2014-03-11_a" />

On 18&nbsp;March, the Chinese government announced that it had checked all of the Chinese citizens on the aircraft and had ruled out the possibility that any were involved in "destruction or terror attacks".<ref name="AutoVQ-43"/>

=== Cargo ===
Flight 370 was carrying {{convert|10806|kg|lb|abbr=on}} of cargo, of which four [[unit load device]]s (standardized cargo containers) of [[mangosteen]]s (a tropical fruit) (total {{Convert|4566|kg|lb|abbr=on}}) and {{convert|221|kg|lb|abbr=on}} of [[lithium-ion battery|lithium-ion batteries]] were of interest, according to Malaysian investigators.<ref name="Interim report-March 2015" />{{Rp|103, 107–109}} According to the [[Inspector-General of Police (Malaysia)|head of Malaysian police]], [[Khalid Abu Bakar]], the people who handled the mangosteens and the Chinese importers were questioned to rule out sabotage.<ref name="Telegraph: Mangosteens">{{cite news|last1=Pearlman|first1=Jonathan|title=MH370: Malaysian police probe fruit farmers as investigation widens|url=https://www.telegraph.co.uk/news/worldnews/asia/malaysia/10742287/MH370-Malaysian-police-probe-fruit-farmers-as-investigation-widens.html |archive-url=https://ghostarchive.org/archive/20220110/https://www.telegraph.co.uk/news/worldnews/asia/malaysia/10742287/MH370-Malaysian-police-probe-fruit-farmers-as-investigation-widens.html |archive-date=10 January 2022 |url-access=subscription |url-status=live|access-date=1 August 2015|work=The Telegraph|date=3 April 2014}}{{cbignore}}</ref>

The lithium-ion batteries were contained in a {{convert|2453|kg|lb|abbr=on|adj=on}} consignment being shipped from [[Motorola Solutions]] facilities in [[Bayan Lepas]], Malaysia, to [[Tianjin]], China. They were packaged in accordance with IATA guidelines, but did not go through any additional inspections at Kuala Lumpur International Airport before being loaded onto Flight 370;<ref name="Interim report-March 2015" />{{Rp|104}} Lithium-ion batteries can cause intense fires if they overheat and ignite, which has occurred on other flights,<ref name="JOC: Cathay ban li-ion bulk shipments">{{cite news|last1=Knowler|first1=Greg|title=Cathay slaps blanket ban on bulk lithium battery shipments|url=http://www.joc.com/air-cargo/cathay-slaps-blanket-ban-bulk-lithium-battery-shipments_20150415.html|access-date=1 August 2015|work=The Journal of Commerce|date=15 April 2015|archive-date=23 September 2015|archive-url=https://web.archive.org/web/20150923004445/http://www.joc.com/air-cargo/cathay-slaps-blanket-ban-bulk-lithium-battery-shipments_20150415.html|url-status=live}}</ref><ref name="BBC: Li-ion batteries aircraft fires">{{cite news|title=Safety worries lead U.S. airline to ban battery shipments|url=https://www.bbc.com/news/technology-31709198|access-date=1 August 2015|work=BBC News|date=3 March 2015|archive-date=27 July 2015|archive-url=https://web.archive.org/web/20150727041253/http://www.bbc.com/news/technology-31709198|url-status=live}}</ref><ref name="USA Today: UPS Flight 6">{{cite news|last1=Jansen|first1=Bart|title=Crash investigators trace UPS plane fire to batteries|url=https://www.usatoday.com/story/news/nation/2013/07/24/ups-crash-dubai-lithium/2582213/|access-date=1 August 2015|work=USA Today|date=25 July 2013|archive-url=https://web.archive.org/web/20201111054236/https://eu.usatoday.com/story/news/nation/2013/07/24/ups-crash-dubai-lithium/2582213/|archive-date=11 November 2020|url-status=live}}</ref>  and has led to strict regulations on transport aircraft.<ref>{{cite news|last1=Levin|first1=Alan|title=Exploding Lithium Batteries Riskier to Planes: Research|url=https://www.bloomberg.com/news/articles/2014-08-11/exploding-lithium-batteries-riskier-to-planes-research|access-date=1 August 2015|work=Bloomberg Business|date=11 August 2014|archive-date=11 September 2015|archive-url=https://web.archive.org/web/20150911090720/http://www.bloomberg.com/news/articles/2014-08-11/exploding-lithium-batteries-riskier-to-planes-research|url-status=live}}</ref><ref name="JOC: Cathay ban li-ion bulk shipments"/>

=== Unresponsive crew or hypoxia ===
An analysis by the ATSB comparing the evidence available for Flight 370 with three categories of accidents—an in-flight upset (e.g., [[Stall (fluid mechanics)#Aerodynamic description of a stall|stall]]), a [[Gliding flight|glide event]] (e.g., engine failure, fuel exhaustion), and an [[Uncontrolled decompression#Gradual decompression|unresponsive crew or hypoxia event]]—concluded that an unresponsive crew or hypoxia event "best fit the available evidence" for the five-hour period of the flight as it travelled south over the Indian Ocean without communication or significant deviations in its track,<ref name=ATSB />{{rp|34}} likely on autopilot.<ref name=Reuters-26June /><ref name=WSJ-26June /> No consensus exists among investigators on the unresponsive crew or hypoxia theory.<ref name=NYT-hypoxia>{{cite news|last1=Bradsher|first1=Keith|title=Pressure Loss Is Explored in Vanishing of Jetliner|url=https://www.nytimes.com/2014/06/27/world/asia/malaysia-airlines-flight-370.html|access-date=29 June 2014|work=[[The New York Times]]|date=27 June 2014|archive-date=29 June 2014|archive-url=https://web.archive.org/web/20140629041010/http://www.nytimes.com/2014/06/27/world/asia/malaysia-airlines-flight-370.html|url-status=live}}</ref> If no control inputs were made following flameout and the disengagement of autopilot, the aircraft would likely have entered a [[spiral dive]]<ref name=ATSB />{{rp|33}} and entered the ocean within {{convert|20|nmi|km mi|abbr=on}} of the flameout and disengagement of autopilot.<ref name=ATSB />{{rp|35}}<!-- at this point the report refers to an inflight upset followed by loss of control, which in the case of Flight 370 would mean flameout and the disengagement of autopilot -->

The analysis of the flaperon showed that the landing flaps were not extended, supporting the spiral dive at high speed theory.<ref>{{cite news |url=http://edition.cnn.com/2016/11/02/asia/mh370-crash-landing-report/index.html |title=MH370 out of control and spiraling fast before crash, report says |work=[[CNN]] |last=Westcott |first=Ben |date=3 November 2016 |access-date=7 July 2017 |archive-date=30 July 2017 |archive-url=https://web.archive.org/web/20170730061918/http://edition.cnn.com/2016/11/02/asia/mh370-crash-landing-report/index.html |url-status=live }}</ref> In May 2018, the ATSB again asserted that the flight was not in control when it crashed, its spokesperson adding that "We have quite a bit of data to tell us that the aircraft, if it was being controlled at the end, it wasn't very successfully being controlled."<ref name="Uncontrolled Spiral Crash into the Sea">{{cite web |url=https://www.bbc.com/news/world-australia-44216778 |title=MH370 not deliberately crashed by pilot, say investigators |date=22 May 2018 |website=[[BBC News]] |access-date=24 May 2018 |archive-date=24 May 2018 |archive-url=https://web.archive.org/web/20180524073124/http://www.bbc.com/news/world-australia-44216778 |url-status=live }}</ref>