Revised May 2024

Malaysia Airlines Flight 370 (MH370) disappeared on March 8, 2014, at 12.41 am after leaving Kuala Lumpur in Malaysia for Beijing in China. There were 227 passengers and 12 crew members on board.

The plane, a Boeing 777, was piloted by Captain Zaharie Ahmad Shah, 53, and co-pilot Fariq Abdul Hamid, 27. The flight was scheduled to take six hours. It left on time at 12:42 a.m.

40 minutes into the flight, the plane diverted from its scheduled route and flew towards the southern Indian Ocean. The flight then vanished from radar, with an international search and salvage operation that lasted until 2018 at a cost of up to $200 million. A decade on, MH370 has not been found.

Initially, many experts questioned why so little debris had been found, given that the plane would have broken into thousands of pieces, many of which floated on water and would have been seen washing up on regional shores or easily spotted by search teams. Those criticisms diminished after several pieces of the aircraft were positively identified in the years after its disappearance.

Several theories, including those with a conspiratorial twist about the disappearance, have emerged. The mystery of what happened to MH370 remains unsolved.

In August 2017, Zahid Raza, the honorary Malaysian consul in Madagascar, was shot dead in Madagascar’s capital Antananarivo in an apparent assassination. Amateur US flight investigator Blaine Gibson, who worked with Raza in tracking down debris from the plane, told Malay Mail that the diplomat “appeared to have been specifically targeted” and claimed that he had also received death threats.

Dr Victor Iannello, an original member of the independent group of specialists that helped Australian investigators try to locate the plane’s crash site, said the timing of Raza’s assassination just days before he was due to deliver several new pieces of debris to the Malaysian Ministry of Transport, “makes a possible link to MH370 even more suspicious”.

Coincidentally, EgyptAir flight MS804 vanished over the Mediterranean on 19 May 19, 2016, exactly 804 days after MH370 vanished.

MH370 crew and passengers

The plane had 10 flight attendants, all Malaysian looking after 227 passengers, including five children. Most of the passengers were Chinese; of the rest, 38 were Malaysian, and in descending order, the others came from Indonesia, Australia, India, France, the United States, Iran, Ukraine, Canada, New Zealand, the Netherlands, Russia, and Taiwan.

Communications with Malaysian Airlines MH370?

At 1.01 am Captain Zaharie radioed that they had leveled off at 35,000 feet and at 1.08 am the flight crossed the Malaysian coastline and set out across the South China Sea in the direction of Vietnam. The Captain again reported the plane’s level at 35,000 feet.

Eleven minutes later, as the airplane closed in on a waypoint near the start of Vietnamese air traffic jurisdiction, the controller at Kuala Lumpur Center radioed, “Malaysian three-seven-zero, contact Ho Chi Minh one-two-zero-decimal-nine. Good night.” Zaharie answered, “Good night. Malaysian three-seven-zero.” He did not read back the frequency, as he should have, but otherwise, the transmission sounded normal. It was the last anyone heard from MH370.

A few seconds after MH370 crossed into Vietnamese airspace, the symbol representing its transponder vanished from the screens of Malaysian Air traffic control, and 37 seconds later, the entire aeroplane disappeared from secondary radar. The time was 1.21 am, 39 minutes after takeoff. The controller in Kuala Lumpur was dealing with other traffic elsewhere on his screen and didn’t notice the transponder-related change. When he finally did, he assumed that the airplane was in the hands of Ho Chi Minh, somewhere out beyond his range.

The pilots never checked in with Vietnamese air traffic control at Ho Chi Minh or answered any of the subsequent attempts to raise them. The Vietnamese ATC began asking about the location of MH370 at 1.38 am local time after it disappeared from their radar screens and did not make verbal contact. Nearby aircraft were asked to contact it if they could, and Kuala Lumpur air traffic control tried the airline and its counterparts in Singapore, Hong Kong, and Phnom Penh as it searched for the plane.

The Vietnamese controllers apparently misunderstood a formal agreement by which Ho Chi Minh was supposed to inform Kuala Lumpur immediately if a plane that had been handed off was more than five minutes late checking in. They tried repeatedly to contact the aircraft, to no avail. By the time they picked up the phone to inform Kuala Lumpur, 18 minutes had passed since MH370’s disappearance from their radar screens. What ensued was an exercise in confusion and incompetence. Kuala Lumpur’s Aeronautical Rescue Coordination Centre should have been notified within an hour of the disappearance. By 2:30 a.m., it still had not been.

At 2.03 am, Malaysian air traffic controllers told Vietnamese ATC that, according to Malaysian Airlines, the aircraft was in Cambodian airspace. Only at 3.30 am did they clarify that the apparent position was a projection based on the earlier flight path and not on any current signal.

Four more hours elapsed before an emergency response was finally begun, at 6.32 am.

The path of MH370 and the ACARS system

Planes communicate with ground radar systems via their transponders and Acars systems. ACARS (pronounced AY-CARS) is a digital data link system for the transmission of messages between aircraft and ground stations.

On MH370, both of those systems appear to have been disabled around the time that the plane disappeared. The last ACARS message was at 1.07 am, and the last transponder contact was at 1.21 am.

But the Acars system continued to make contact with satellites, and data shows that the plane flew on for several hours, with the last "handshake" at 8.19 am.

Malaysia's acting transport minister, Hishammuddin Hussein, said Malaysian military radar tracked MH370 turning back across the Malay peninsula, but the operator categorized it as friendly, so it took no further action.

The radar data was reviewed at 8:30 am on March 8, and within hours, the prime minister ordered search and rescue operations to begin in the Straits of Malacca, off the west coast, in addition to the South China Sea search that had already begun. But news of a possible turn-back was not revealed until the following day, and even then, no detail was offered.

Primary radar records from air traffic control computers and military data revealed that as soon as MH370 disappeared from secondary radar, it turned sharply to the southwest, flew back across the Malay Peninsula, and banked around the island of Penang. From there it flew northwest up the Strait of Malacca and out across the Andaman Sea.

It turned out that MH370 had continued to link up intermittently with a geostationary Indian Ocean satellite run by Inmarsat, a London-based company, for six hours after the airplane disappeared from secondary radar. This meant that it had not immediately crashed.

The Inmarsat linkups, some of them known as “handshakes,” were routine connections because the intended system for passenger entertainment, cockpit texts, and automated maintenance reports had been isolated or switched off.

Seven linkups were initiated—two by the airplane and five by the Inmarsat ground station. Two satellite phone calls went unanswered but provided additional data.

Associated with most of these connections were two values that Inmarsat had only recently begun to log. The first and more accurate of the values is known as the burst-timing offset, or “distance value.” It is a measure of the transmission time to and from the airplane and, therefore, of the plane’s distance from the satellite. It does not pinpoint a single location but rather all equidistant locations, a roughly circular set of possibilities. Given the range limits of MH370, the near-circles could be reduced to defined arcs. The most important arc was the seventh and last one, defined by a final handshake tied in complex ways to fuel exhaustion and the failure of the main engines. The seventh arc stretches from Central Asia in the north to the vicinity of Antarctica in the south. It was crossed by MH370 at 8.19 am Kuala Lumpur time. Calculations of the likely flight paths placed the aeroplane’s intersection with the seventh arc and, therefore, its endpoint in Kazakhstan if the aeroplane turned north or in the southern Indian Ocean if it turned south.

Technical analysis indicated with near certainty that the plane turned south because of Inmarsat’s second logged value, the burst-frequency offset or the “Doppler value”. It includes a measure of radio-frequency Doppler shifts associated with high-speed movement in relation to satellite position and is a natural part of satellite communications for airplanes in flight. Doppler shifts have to be predicted and compensated for by airborne systems in order for satellite communications to function. But the compensation is not quite perfect, because satellites, particularly as they age, do not transmit signals in precisely the way airplanes have been programmed to expect. Their orbits may tilt slightly and they are also affected by temperature. These imperfections leave telltale traces. Although Doppler-shift logs had never been used before to determine the location of a plane, Inmarsat technicians in London were able to discern a significant distortion suggesting a turn to the south at 2:40 a.m. The turning point was a bit north and west of Sumatra, the northernmost island of Indonesia. It has been assumed, at some analytical risk, that the plane then flew straight and level for a very long while in the general direction of Antarctica, which lay beyond its range.

After six hours, the Doppler data indicated the plane had gone into a steep descent. As much as five times greater than a normal descent rate. Within a minute or two of crossing the seventh arc, the plane dived into the ocean and this was not a controlled attempt at a water landing. But no one knew where the impact had occurred.

The search for the plane

The search for the plane was initially focused in the South China Sea, between Malaysia and Vietnam. 34 ships and 28 aircraft from seven different countries were involved, but MH370 could not be located. Partly because the Malaysians had not shared all the data they had.

The surface-water search ended in April 2014. Although the Malaysians were in charge of the entire investigation, they lacked the means and expertise to mount a subsea search-and-recovery effort. The Australians took the lead. The effort focused on the areas of the Indian Ocean that the satellite data pointed to, about 1,200 miles southwest of Perth.

Then after more than three years, the Australian investigation closed without success. It was picked up in 2018 by an American company called Ocean Infinity, under contract with the Malaysian government on a “no-find, no-fee” basis. This search used advanced underwater surveillance vehicles and covered a new section of the seventh arc, a section deemed most likely by the Independent Group to bring results. After a few months, it, too, ended in failure.

Clues to the disappearance

Possible sighting of the plane in the Maldives

On March 18, 2014, journalists Farah Ahmed and Ahmed Naif, working for the Maldivian newspaper Haveeru, wrote: "...several residents of Kuda Huvadhoo told Haveeru on Tuesday that they saw a 'low flying jumbo jet' at around 06:15 on March 8. They said that it was a white aircraft with red stripes across it—which is what Malaysia Airlines flights typically look like. Eyewitnesses from the Kuda Huvadhoo concurred that the jet was traveling North to South-East, towards the Southern tip of the Maldives—Addu. They also noted the incredibly loud noise that the flight made when it flew over the island. 'I've never seen a jet flying so low over our island before. We've seen seaplanes, but I'm sure that this was not one of those. I could even make out the doors on the plane clearly.' said an eyewitness. 'It's not just me either, several other residents have reported seeing the exact same thing. Some people got out of their houses to see what was causing the tremendous noise too.'

Discovery of Debris

On July 29, 2015, a municipal beach cleanup crew on the French island of Réunion, east of Madagascar, came upon a torn piece of airfoil about six feet long that seemed to have just washed ashore. The foreman of the crew, Johnny Bègue, realized that it might have come from a plane. He called a local radio station with the news and gendarmes arrived and took the piece of the plane away. It was quickly confirmed to be a part of a Boeing 777, a control surface called a flaperon that is attached to the trailing edge of the wings. Subsequent examination of serial numbers showed that it had come from MH370.

Professor Charitha Pattiaratchi, from the University of Western Australia, said that "the arrival of MH370 debris in Réunion would conform to the expected path of ocean currents from the point in its flight path where it was believed to have crashed".

In June 2016, on the northeastern shores of Madagascar, locals found several pieces of the plane.

Timeline of events relating to the MH370 mystery

March 8, 2014

12:41 am Flight departs Kuala Lumpur, Malaysia to Beijing, China.

1:37 am, MH370’s regularly scheduled 30-minute automatic condition-reporting system failed to transmit. System isolated from any satellite transmission using cockpit control.

1:52 am, MH370 passed just south of Penang Island, made a wide right turn, and headed northwest up the Strait of Malacca. As the airplane turned, the first officer’s cellphone registered with a tower below. It was a single brief connection, during which no content was transmitted. Eleven minutes later, on the assumption that MH370 was still over the South China Sea, a Malaysia Airlines dispatcher sent a text message instructing the pilots to contact Ho Chi Minh’s air traffic control center. The message went unanswered. Through the Strait of Malacca, the airplane appeared to be hand-flown.

2:22 am The Malaysian air-force radar picked up the last blip of the plane on radar. The plane was 230 miles northwest of Penang, heading northwest into the Andaman Sea and flying fast.

2:25 am MH370’s satellite box came back to life. It is likely that this occurred when the full electrical system was brought back up and that the plane was repressurized at the same time. When the satellite box came back on, it sent a log-on request to Inmarsat and the ground station responded. The first linkup was accomplished with Immarsat and relevant distance and Doppler values were recorded at the ground station, later allowing the first arc to be established.

A few minutes later a dispatcher put in a phone call to the airplane. The satellite box accepted the link, but the call went unanswered. An associated Doppler value showed that the airplane had just made a wide turn to the south. To investigators, the place where this happened became known as the “final major turn.” Its location is crucial but the exact location has never been fully determined. Indonesian air-defense radar should have shown it, but the radar seems to have been turned off for the night.

Theories on what happened to MH370

Murder-suicide

Captain Zaharie Ahmad Shah's wife and his three children moved out of his house the day before the disappearance and it was claimed that he may have been seeing another woman. A fellow pilot and long-time associate of Shah stated the Captain was "terribly upset”, that his marriage was falling apart.

Police also investigated reports that Shah received a two-minute phone call prior to the flight's departure from an unidentified woman using a mobile phone number obtained with a false identity.

The FBI reconstructed the deleted data from Captain Shah's home flight simulator with a Malaysian government spokesman indicated that "nothing sinister" had been found on it. However, it was later reported by the media that among deleted flight paths performed on the flight simulator, investigators found a flight path into the Southern Ocean where a simulated landing was made on an island with a small runway.

By the time the plane dropped from the view of secondary transponder-enhanced radar, it is likely, given the fact that the two pilots were acting together, that one of them was out of action or dead or had been locked out of the cockpit. Primary radar records later indicated that whoever was flying MH370 must have switched off the autopilot because the turn the aeroplane then made to the southwest was so tight that it had to have been flown by hand. Whoever was at the controls may have deliberately depressurized the airplane. At about the same time, much, if not all, of the electrical system was deliberately shut down. The reasons for that shutdown are not known. But one of its effects was to temporarily sever the satellite link.

During the turn, the plane climbed up to 40,000 feet, which was close to its limit, and the passengers would have experienced some g‑forces, it could be possible that the reason for the climb was to accelerate the effects of depressurizing the aeroplane, causing the rapid incapacitation and death of everyone in the plane.

An intentional depressurization would have been an obvious way to subdue passengers and other crew. In the cabin, the effect would have gone unnoticed but for the sudden appearance of the drop-down oxygen masks and perhaps the cabin crew’s use of the few portable units of similar design. None of those cabin masks was intended for more than about 15 minutes of use during emergency descents to altitudes below 13,000 feet, they would have been of no value at all cruising at 40,000 feet. The cabin occupants would have become incapacitated within a couple of minutes, lost consciousness, and died because of a lack of oxygen.

The cockpit, by contrast, was equipped with four pressurized oxygen masks with several hours of supply.

MH370 was now most likely flying on autopilot.

Freescale Semiconductor link

MH370 was carrying twenty employees of US technology company Freescale Semiconductor, which had a large semiconductor manufacturing facility near Kuala Lumpur.

Freescale Semiconductor, Inc. was an American semiconductor manufacturer created by the divestment of the Semiconductor Products part of Motorola in 2004. It was bought by a private investor group in 2006 and subsequently merged into NXP Semiconductors in 2015.

It manufactured microchips for different sectors, including the defense industry. Twelve employees were from Malaysia, and eight were from China. There were some theories that several of the employees of the plane were about to submit a parent for the dyes used on semiconductor boards, but this does seem to be a reason to take down the plane, especially as the patent owner would have reverted to Freescale in the event of their deaths.

Hijack

This seems unlikely given the cockpit door was fortified and electrically bolted with CCTV.

Less than two minutes passed between Captain Zaharie’s “good night” to the Kuala Lumpur controller and the start of the diversion, with the loss of the transponder signal. Would hijackers know to make their move precisely during the handoff to Vietnamese air traffic control, and then gain access to the cockpit without the Captain and his first officer making a distress call to ATC? Unless the hijackers and pilots were planning the hijack together.

But why was there no radio transmission, particularly during the hand-flown turn away from China as both of the control yokes had transmitter switches within easy reach?

Furthermore, every one of the passengers and cabin crew members has been investigated and cleared of suspicion by teams of Malaysian and Chinese investigators aided by the FBI.

Two Iranians were traveling on the plane using false names with stolen passports, but it was confirmed that their goal was political asylum in Germany. If someone had hidden in the plane ready to take it over or had access to the equipment, they could have activated circuit breakers, which would have unbolted the cockpit door. But the bolts click loudly when they open. The hijackers would then have had to open a galley-floor hatch from below and climb a short ladder, sneak past the cabin crew, remain unnoticed by the CCTV surveillance video, and enter the cockpit before either of the pilots transmitted a distress call.

No one has claimed responsibility for the act if the plane was actually hijacked.

Unintentional Oxygen deprivation

A sudden cabin depressurization may have occurred, which could have caused the crew and passengers to blackout and perhaps caused the Captain and co-pilot to carry on flying - the so-called “ghost Plane” scenario. The pilots were partially able to function but were impacted by oxygen deprivation, explaining the erratic route it took after losing contact, before finally ditching somewhere in the Indian Ocean.

Fire in the plane caused by batteries

Could the disappearance have been caused by a fire in the cockpit, cargo compartment, landing gear, or another part of the plane? But this would not explain the diversion of the plane unless the crew was aware of a fire in the part of the hold which stored the electronics and lost control of the systems as they failed.

The plane’s manifest showed it was carrying a large cargo of unknown electronics from Motorola and 221kg of Lithium-ion batteries which have been known to spontaneously catch fire. MH370 also had in its cargo hold 5 tons of mangosteens, a sweet tropical fruit.

A report by Malaysia's Science & Technology Research Institute for Defence noted in 2018 that "There were concerns that the mangosteen extracts could have got into contact with the batteries and produced hazardous fumes or in a worst-case scenario caused a short circuit and/or fire."

After carrying out tests the institute was "convinced that the two items tested could not be the cause in the disappearance of MH370. The report said that the notion that the two products got into contact is "highly improbable” as the items were in a hold compartment together, but said both the batteries and fruit were wrapped up and in separate containers.

The batteries were not registered as dangerous goods as their packaging adhered to guidelines. They went through customs inspection and clearance before the truck was sealed and left the factory, but were not given any additional security screening before being loaded onto the plane. Between January 2014 and May 2014, it said, there were 99 shipments of lithium-ion batteries on Malaysia Airlines flights to Beijing.

The report also disputed speculation that the mangosteen fruits were out of season during the shipment, which led some to suggest their inclusion in the cargo was suspicious. The report states that they were in season in neighboring countries, where they were harvested. The fruit was inspected by the Federal Agriculture Marketing Authority of Malaysia before it was loaded onto the aircraft. Between January and May 2014, there were 85 shipments of mangosteens to Beijing. The two were carried together on 26 of these flights.

The police interviewed everyone who handled the cargo, as well as the fruit suppliers and battery manufacturers.

Therefore, according to the Malaysian government, neither batteries nor fruit were a factor.

More bizarre explanations for the MH370 incident

MH370-obsessed individuals using chat rooms and blogs have proposed many more bizarre and sinister explanations for the disappearance of MH370. Many of these theories seem far-fetched but have some elements of fact in their narrative.

The Indian Ocean Bermuda Triangle or Alien Abduction

Just like the Bermuda Triangle, could there be a similar phenomenon somewhere in the Indian Ocean? But this would not explain strange events like the transponder switch off and sudden turn to the North, as well as the satellite pings.

Remote cyber hijacking

The former Malaysian prime minister Mahathir Mohamad said in 2014, "Clearly Boeing and certain agencies have the capacity to take over uninterruptible control of commercial airliners of which MH370 B777 is o” In this statement, he was referring to off-board hijackers with access to MH370's Boeing’s Honeywell Flight Management System via the 2003 patented Uninterruptible Autopilot.

In Norman Davies’ 2017 book, “Beneath Another Sky: A Global Journey into History”, he proposed that technology designed to prevent another 9-11 terror attack by allowing planes to be controlled remotely could have been exploited by criminals or government-controlled agencies. He wrote that MH370 could have been hacked and then reprogrammed and flown to a secret location. He concludes: “It must be a near certainty that someone in the world knows more about MH370 than they have chosen to reveal.” But who?

The Cambodia connection

In 2018, a British video producer named Ian Wilson claimed to have spotted the aircraft's remains in the Cambodian jungle using Google Maps. This has never been confirmed.

Diego Garcia theory

Marc Dugain, who once ran French airline Proteus, who had been investigating the disappearance has claimed that the missing plane was shot down by American fighter jets who feared that it had been hijacked and was about to be used to attack the US military base on the Indian Ocean atoll of Diego Garcia.

Sources

https://www.theweek.co.uk/mh370/58037/mh370-conspiracy-theories-what-happened-to-the-missing-plane

https://en.wikipedia.org/wiki/Malaysia_Airlines_Flight_370_disappearance_theories

https://en.wikipedia.org/wiki/ACARS

https://www.theguardian.com/world/2014/may/01/mh370-report-real-time-tracking-planes

https://www.theatlantic.com/magazine/archive/2019/07/mh370-malaysia-airlines/590653/

https://nymag.com/intelligencer/2015/02/jeff-wise-mh370-theory.html

https://www.businessinsider.com/mh370-report-quashes-theory-that-batteries-and-fruit-cargo-caused-explosion-2018-8?r=US&IR=T