At 00:41 on 8 March 2014, Malaysia Airlines flight MH370 took off from runway 32R at Kuala Lumpur International Airport, bound for Beijing with 227 passengers and 12 crew.

At 01:19 someone in the cockpit bade farewell to Malaysian air traffic control with the words: “Good night, Malaysian three seven zero.”

Those were the last words ever heard from flight MH370.

The last radar contact was at 02:22, the final automatic “partial handshake” with a satellite above the Indian Ocean was at 08:19.

And then MH370, with 239 people on board, seemingly vanished into thin air.

As the conspiracy theories swirled – ranging from a secret landing on the US airbase of Diego Garcia, to the world’s first remote-controlled “cyberhijack” – the search for MH370, costing $160m (£125m), became the most expensive in aviation history.

At one point those seeking the final resting place of the missing Boeing 777 faced having to scour about 1.5 per cent of the Earth’s surface, nearly three million square miles, in two arcs stretching from northern Thailand to Kazakhstan, and from Indonesia into the southern Indian Ocean.

They soon “narrowed it down” to a vast, remote area of the southern Indian Ocean, braving the effects of tropical cyclones and some of the roughest waters on the planet to use drones and sonar equipment to scour an area of seabed that was less well-known than the surface of the moon.

They found new underwater volcanoes, anchors, long-lost wrecked ships, but no sign of the bulk of MH370.

Then in January this year, after searching 120,000 square km (46,300 square miles) of ocean, the Malaysian, Australian and Chinese authorities announced that their search was being “suspended”.

The search for MH370 became the most expensive in aviation history (Getty) (Getty Images)

Despite every effort,” said the communique from the Joint Agency Coordination Centre (JACC), “using the best science available, cutting edge technology, as well as modelling and advice from highly skilled professionals who are the best in their field, unfortunately, the search has not been able to locate the aircraft.”

And so three years on, for the relatives, the anguish of not knowing what happened to the 239 remains as raw as ever. Because there can be no doubt that the ending of the search has done nothing at all to close down speculation about the fate of MH370 and those who flew in it.

Indeed it seems the plot has now thickened further. Research commissioned by the Australian Transport Safety Bureau has now suggested that for a large part of the search for MH370, everyone was looking in the wrong place.

Since November 2015 the search had prioritised an area between the latitudes 36°S and 39.3°S. But the new research suggests the wreck of the bulk of the plane is further north, in a region near 35°S.

Scientists from Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO) based their findings on the first piece of MH370 debris to be found: a flaperon, an aircraft wing part functioning as both flaps and ailerons, that drifted across the ocean until it was found by a council worker having his lunch break in July 2015 on a beach on the island of Réunion, east of Madagascar.

MH370 wreckage confirmed

The scientists acquired a genuine Boeing 777 flaperon, cut it down to match photographs of the MH370 flaperon found on the beach, and then analysed how it drifted over water.

The resulting drift patterns and the fact that so far MH370 debris has been found on Réunion, Madagascan and African shores but not on Australian beaches led them to conclude: “The region near 35°S is the only one that is consistent. The available evidence suggests that all other regions are unlikely.”

The publication of this report has added further weight to the argument advanced by the anguished relatives since January: that the search had ended too soon, that if a new 25,000km² (9,650mi²) area could be examined, the mystery of MH370 could finally be solved.

The search areas as they were before the official hunt for MH370 was suspended

And it is correct to talk about adding further weight: because the CSIRO scientists stressed that their report merely added a greater degree of certainty to their earlier drift analysis, the one they conducted last year using a replica flaperon.

This earlier drift analysis had informed a “First Principles Review” of the MH370 search, conducted under the auspices of the Australian Transport Bureau.

As a result, in December 2016 – one month before the search was called off – the First Principles Review had recommended examining a new, more northerly area – the 25,000km² patch of ocean subsequently cited by the relatives.

And yet the January JACC communique announcing the suspension of the search appeared to brush this aside by stating: “Whilst combined scientific studies have continued to refine areas of probability, to date no new information has been discovered to determine the specific location of the aircraft.”

A sand sculpture made in March 2014 on Puri Beach, India (AFP/Getty) (AFP/Getty Images)

If the new CSIRO report were not enough to prompt renewed controversy, as so often happens with the mystery of MH370, an alternative narrative has also swiftly emerged.

Last Sunday a loose affiliation of interested scientists calling themselves the Independent Group revealed drift analysis of their own, conducted by Richard Godfrey, suggesting that the wreck of MH370 might lie around latitude 30°S, much further north than even the new 35°S area.

“The pre-conceived idea, that ‘other evidence’ constrains the MH370 End Point to between 32°S and 36°S is a false assumption,” insisted Godfrey, a Frankfurt-based aerospace engineer.

He wondered, for example, about the CSIRO factoring into its calculations the absence of MH370 debris in Australia.

Wasn’t it possible, he suggested, that something could have washed up unnoticed somewhere along the 20,781 km (12,913 miles) of the relatively sparsely populated coast of western Australia, where 86 per cent of the population lives within the cities of Perth, Bunbury, Busselton and Mandurah?

Godfrey also suggested that much of the area around 35°S had in fact been searched prior to November 2015 – despite the CSIRO report having sought to explain that “the new search area, near 35°S, comprises thin strips either side of the previously-searched strip”.

In his report summary, Godfrey seemed to go as far as flatly contradicting this CSIRO explanation by asserting that: “An MH370 End Point at 35°S does not fit the fact that the underwater search has already discounted this location to a 97 per cent level of certainty.”

In pictures: Theories that could explain what happened to MH370 Show all 14 1 /14 In pictures: Theories that could explain what happened to MH370 In pictures: Theories that could explain what happened to MH370 Shot down in a military training exercise While the Australian officials leading the search for MH370 say they remain “absolutely convinced” it ended up in the southern Indian Ocean, some passengers’ families – and theorists – distrust the unprecedented satellite data analysis involved. Among those who support this view are the British journalist and author Nigel Cawthorne, who has controversially already published the first book on the plane’s disappearance. e supports one theory, based on the eye-witness testimony of New Zealand oil rig worker Mike McKay, that the plane was shot down shortly after it stopped communicating with air traffic controllers. At the time there was a series of war games taking place in the South China Sea involving Thailand, the US and personnel from China, Japan, Indonesia and others, and Cawthorne has linked this to Mr McKay’s claims to have seen a burning plane going down in the Gulf of Thailand. In pictures: Theories that could explain what happened to MH370 Stolen by Putin Jeff Wise, a private pilot and science writer, claims he has evidence that the plane made its way to the Baikonur Cosmodrome in Kazakhstan, which is run by Russia as its largest space launch facility. He claims Vladimir Putin ordered Russian special forces to hijack MH370 and fly it to the spaceport, but admits he has 'no idea' why the Russian president would want to do such a thing Getty Images In pictures: Theories that could explain what happened to MH370 Flown north and shot down deliberately, prompting cover-up At a stage in the investigation when it was believed the plane could have flown for some time from where it disappeared along either a northern or southern corridor, many posted on forums suggesting that if it had been the former we would never hear about what happened. Some still support this view, and former RAF navigator Sean Maffett told the BBC that after 9/11, any unidentified airliner entering the airspace of another country would lead to fighter jets being scrambled. “If the plane is in the northern arc it could easily have been shot down,” he said. This theory also involves a national – or possibly international – cover-up, based on the premise that no country would want to admit to shooting down an airliner full of passengers from all over the world. In pictures: Theories that could explain what happened to MH370 Flown north in the ‘shadow’ of another plane Another theory suggests that instead of flying south, the plane flew north in the “shadow” of another airliner around half an hour to an hour after dropping off civilian radar. The aviation blogger Keith Ledgerwood argued that MH370 and Singapore Airlines flight 68 were in the same vicinity at the time, and said: “It became apparent as I inspected SIA68's flight path history that MH370 had manoeuvred itself directly behind SIA68 at approximately 18:00UTC and over the next 15 minutes had been following SIA68.” By flying a short distance behind and most likely a little above the altitude of SIA68, also a Boeing 777, Ledgerwood said that it would be able to appear as a single blip on radar screens. SIA68 flew on to Spain – and this theory suggests MH370 could have branched off and landed in one of a number of locations across Xinjiang (north-east China), Kyrgyzstan or Turkmenistan. Experts have said that the idea sounds “feasible”, and that even if higher-resolution military radar was monitoring SIA68 operators might have dismissed the fact that there were two objects as an technical glitch or echo. AP In pictures: Theories that could explain what happened to MH370 Tried to land on a desert island beach After reports that the plane had turned left shortly following its disappearance from civilian radar screens, speculation grew that it could have landed on a remote beach somewhere like the Andaman Islands, which lie between Indonesia and the coast of Thailand. Though CNN reported that locals dismissed the idea a Boeing 777 could land on an airstrip there undetected, the archipelago consists of hundreds of remote islands with some long stretches of sand. Former BA pilot Steve Buzdygan said it would be difficult – but not impossible – to bring a 777 down on a long deserted beach. AP In pictures: Theories that could explain what happened to MH370 Landed at a US military base One of the more outlandish conspiracy theories that has gained some traction online is the idea that MH370 could have been “captured” and flown to a military base on the UK-owned tropical atoll of Diego Garcia, in the middle of the Indian Ocean. The base is run by the US, and some have reportedly said in forum postings that the Kremlin has put some credence into this possibility. Such is the strength of belief in this theory that the US government has been forced to issue a denial. A spokesperson for the US embassy in Malaysia told the local Star newspaper that there was “no indication that MH370 flew anywhere near the Maldives or Diego Garcia”. “MH370 did not land in Diego Garcia,” he added. Nasa In pictures: Theories that could explain what happened to MH370 Headed for a remote airport in Langkawi, Malaysia One theory, put forward by another aviation blogger named Chris Goodfellow, has it that the sudden left turn came after major catastrophe knocked out a range of the plane’s electronics, from transponders to communications equipment. In this scenario and in the middle of the night, Goodfellow argued, the pilot would redirect towards the nearest safe airport. “This pilot did all the right things,” he said. “Actually he was taking a direct route to Palau Langkawi, a 13,000ft (4,000m) strip with an approach over water at night with no obstacles. He did not turn back to Kuala Lumpur because he knew he had 8,000ft ridges to cross. He knew the terrain was friendlier towards Langkawi and also a shorter distance.” This theory assumes that the plane was in fact controlled manually once it disappeared – and that it did not make it to Langkawi. In pictures: Theories that could explain what happened to MH370 A fire throughout the plane Many theories accept that the Inmarsat satellite analysis is accurate – that the plane headed south into the Indian Ocean and flew on for hours before a final, partial “handshake” in a remote location thousands of miles off the west coast of Australia. The issue here becomes explaining what happened in the cabin between the last contact with flight controllers and the plane’s seemingly inevitable crash far out to see. One suggestion is that a fire broke out, not just in the cockpit but throughout the interior of the plane. The implication is that this resulted in the attempt to turn back, after which the fire killed those on board. This theory would then have it that the fire went out before damaging the exterior of the plane, which flew on autopilot until its fuel ran out. Yet such a fire would be expected to spread with at least some warning – and that surely would have given the pilots time to issue a mayday distress signal. In pictures: Theories that could explain what happened to MH370 An explosion in the cockpit The theory of a sudden explosion within the cockpit before the turn left could explain why there was no attempt to signal for help. Since 9/11 cockpits doors have been fortified to become extremely difficult to bypass, and such a sudden incident could perhaps have incapacitated both pilots while keeping out the rest of the crew. This explanation does not seem to tally with the claims of some Malaysian officials, however, that the change in direction was the result of “seven or eight keystrokes into a computer on a knee-high pedestal between the captain and the first officer”. In pictures: Theories that could explain what happened to MH370 A struggle at altitude Though Malaysian officials believe that the plane was deliberately diverted, and that its communications systems were turned off one after the other, a detailed background check into all 227 passengers has cleared all of suspicion. If, however, we do accept that the plane was the subject of a passenger hijacking, it remains to be explained why the hijackers did not try to do more than fly the plane into the middle of the southern Indian Ocean. One theory suggests that there was some kind of struggle for control of the plane that ultimately ended with mutual destruction. Further analysis of data by Malaysian officials suggests that the plane was flown erratically once it left civilian radar, climbing to 45,000ft before dropping very low. Buzdygan told the BBC he would resort to this sort of flying if faced with would-be hijackers. “I’d try to disorientate and confuse the hijackers by throwing them around,” he said. Getty Images In pictures: Theories that could explain what happened to MH370 A botched hijack attempt The climb to 45,000ft could also have been carried out by the hijackers once they had taken control – in a bid to kill the passengers on board. At such an altitude it could be possible to depressurise the cabin, causing oxygen supplies to be deployed. These run out after 12-15 minutes and, if those flying the plane had access to another oxygen supply, could have been an attempt to prevent anyone intervening. Under this theory the suggestion is clearly that the attempt failed, killing the hijackers as well. Getty In pictures: Theories that could explain what happened to MH370 Pilot suicide As part of the ongoing criminal investigation in Malaysia, police are looking into the state of mind and possible motives of the captain Zaharie Ahmad Shah and co-pilot Fariq Abdul Hamid. The Malaysian police chief Khalid Abu Bakar has said that “all possibilities” will be looked into, and there have been reports that Shah was going through a difficult marriage break-up.Yet such comments have been rubbished by the man’s relatives, who have described him since as a dedicated family man and model professional. Hugh Dunleavy, the commercial director of Malaysia Airlines, described Shah as a seasoned pilot with an excellent record. “There have been absolutely no implications that we are aware of that there was anything untoward in either his behaviour or attitude,” he told Reuters. “We have no reason to believe that there was anything, any actions, internally by the crew that caused the disappearance of this aircraft.” In pictures: Theories that could explain what happened to MH370 Sabotage – for a life insurance scam or corporate attack One of the other strands of the criminal investigation regards whether the plane was subject to some form of sabotage – either as part of a life insurance scam or over industrial espionage. Bakar said that when passengers and crew were being investigated, police were looking for “Maybe somebody on the flight has bought a huge sum of insurance, who wants family to gain from it or somebody who has owed somebody so much money, you know, we are looking at all possibilities.” There were also 20 employees of the US silicon chip company Freescale Semiconductor on board the plane at the time, and a retired Delta Airlines pilot has suggested the plane’s disappearance was an attempt to steal technology the engineers had applied – but not yet received – a patent for. Corbis In pictures: Theories that could explain what happened to MH370 A CIA cover-up Finally, the former prime minister of Malaysia Mahathir Mohamad has waded in with his own theory – suggesting that, one way or another, the CIA is definitely hiding something. In a blog entry posted on 18 May entitled ‘Boeing Technology – What goes up must come down’, Dr Mahathir Mohamad makes ten claims including that the plane was taken over remotely by officials working for Boeing and the CIA. The plane is somewhere, maybe without MAS markings,” reads Dr Mohamad’s post on chedet. “Someone is hiding something. It is not fair that MAS and Malaysia should take the blame,” 88-year-old Dr Mahathir, who was Malaysia's prime minister between 1981 and 2003, alleges. “Airplanes don’t just disappear,” he said, concluding: “For some reason the media will not print anything that involves Boeing or the CIA. I hope my readers will read this.” Boeing have denied Dr Mohamed’s theory. HENNY RAY ABRAMS/AFP/Getty Images

Amid such technicalities remain the relatives of the 239, and the stark question posed by KS Narendran, a human resources consultant from Chennai, India, who has lost Chandrika Sharma, his wife of 25 years.

“How,” he wrote last month, “can a large jetliner claiming to be the safest, most sophisticated and successful commercial aircraft, with hundreds of passengers on board, just disappear?”

Partly, some think, the answer lies with the chaos that attended the first days of the search for MH370.

The initial efforts sent the bulk of 40 search aircraft and 24 boats in completely the wrong direction – to the east, to look in the Gulf of Thailand and the South China Sea between Malaysia and Vietnam.

At first MH370 was not recognised as the unidentified aircraft last picked up at 02:22 by a military radar which placed it 370km (230 miles) from Penang Island on Malaysia’s western coast, far to the west of where everyone was looking.

Only on 10 March, two days after the disappearance, did the Malaysian Air Force admit that MH370 seemed to have made an unexpected sharp “turn back” to the west, deviating from what should have been its easterly course towards Beijing.

The last known movements of MH370 (Andrew Heneen, via Wikimedia Commons)

Adding to the confusion was that the Malaysian authorities reportedly initially denied what analysis of the satellite handshakes was now revealing: that for hours after disappearing from the military radar screen, MH370 had kept on flying.

Only on 15 March, seven days after the disappearance, did Malaysian Prime Minister Najib Razak announce publicly that the South China Sea search would be stopped.

The scenario outlined by the Malaysian PM was now of a jet that had flown on for at least seven hours after the last 01:19 voice message from the cockpit.

The satellite data, he said, suggested the need to look along two possible arcs encompassing a total of nearly three million square miles: the northern one stretching from Thailand to Kazakhstan, the southern from Indonesia into the Indian Ocean.

Further analysis soon allowed the focus to turn exclusively to the southern Indian Ocean.

But by then about 100 relatives waiting for news in Beijing had delivered a handwritten ultimatum demanding proper clarity after so many contradictions.

“We don’t believe Malaysia Airlines any more,” their spokesman told a crowd of reporters. “Sorry everyone, we just don’t believe them.”

Family members still in the dark over fate of MH370

China, its nationals making up two-thirds of the passenger manifest, weighed in with statements stretching the bounds of diplomatic politeness.

The Malaysian prime minister’s 15 March disclosures had been “painfully belated”, said Xinhua, China’s state news agency. “Due to the absence of timely authoritative information, massive efforts have been squandered and numerous rumours have been spawned, repeatedly racking the nerves of the awaiting families.”

It was undeniable that the gap left by an absence of consistent official information was being filled by a whole host of theories, some credible, some completely untethered from reality.

Traumatised relatives found themselves accused online of having faked their relationships with the vanished passengers, as part of some sort of “arch-Zionist” Mossad disinformation plot to spread fear of Islamist terrorism. In one version, they became a “clique of falsifiers” faking relationships with “phony passengers” on a flight that itself had never even existed.

Back in the real world, Najib’s press conference claim that someone had deliberately switched off MH370’s communications reporting system before turning it west re-ignited the hijacking theories.

These had initially focused on two Iranian men named as Pouria Nour Mohammad Mehrdad, 18, and Delavar Seyed Mohammadreza, 29, who had been travelling on stolen passports.

But neither man was found to have had any links with terrorist groups and they were largely written off as asylum seekers travelling – as is relatively common – with false documents.

Instead the speculation turned to other passengers, and the crew – especially the crew.

Captain Zaharie Ahmad Shah, left, and co-pilot Fariq Abdul Hamid

Malaysian police were searching the homes of Captain Zaharie Ahmad Shah and 27-year-old co-pilot Fariq Abdul Hamid.

Captain Shah in particular became the focus of enduring speculation. Perhaps the 53-year-old Muslim wasn’t really the mild-mannered grandfather who raised money for the poor and enjoyed watching recordings of the renowned atheist Richard Dawkins?

Wasn’t he, after all, a supporter of the opposition Malaysian People’s Justice Party?

And most intriguingly of all, what to make of the six-screen flight simulator that he had built in his own home?

Was this really just another “aviation junkie” seeking to share an innocent passion, as suggested by such Facebook posts as: “Time to take to the next level of simulation motion! Looking for buddies to share this passion”?

MH370: A timeline

Over time, speculation about Captain Shah has only intensified. Last July it was reported that an FBI forensic examination of his flight simulator’s hard drive had revealed he had plotted one practice route – among thousands, it should be said – that took an aeroplane into the southern Indian Ocean.

Comparisons started to be drawn between Captain Shah and Andreas Lubitz, the suicidal co-pilot of Germanwings Flight 9525, who in March 2015 had locked the cockpit door and deliberately flown the plane into a French mountainside.

There were unconfirmed reports of a marriage breakdown, speculation about a life insurance scam. Was MH370 another case of pilot suicide-murder?

“Someone was looking at Penang,” experienced Boeing 777 captain Simon Hardy told the BBC in April 2015, after analysing MH370’s last known movements. “Someone was taking a long, emotional look at Penang.

“The captain was from the island of Penang.”

“It flew in and out of the countries [Malaysia and Thailand] eight times,” added Mr Hardy. “This is probably very accurate flying rather than just a coincidence. Both air traffic controllers in both those countries would probably assume that the aircraft was in the other country’s jurisdiction and not pay it any attention.”

Some have sought to match the pilot-suicide theory with investigators’ suggestions that MH370 became a “ghost plane” flying for hours without human control, probably on autopilot, with crew and passengers rendered unconscious or dead by oxygen starvation.

Had a suicidal Captain Shah deliberately depressurised the jet, leaving everyone with just 20 minutes more oxygen, to be breathed from the masks that would have automatically dropped down from above their seats, before unconsciousness rendered them oblivious to their impending deaths?

Other theories have suggested “the world’s first cyber-hijack” using a mobile phone or even a USB stick to hack into the plane’s control software.

Or perhaps Captain Shah was a non-suicidal hero who steered a stricken jet away from heavily populated areas to carry out a controlled ditching in a remote stretch of ocean?

A controlled ditching was, at least, effectively ruled out by the Australian Transport Safety Bureau last November. It reported that examination of wing flap debris that had by now drifted ashore, combined with “burst frequency offset” analysis of the final 08:19 satellite handshake, suggested “a high and increasing rate of descent” of up to 25,000 feet per minute – a death spiral as some commentators have described it.

There are other theories, ranging all the way up to alien abduction, and plenty of seekers. One man, Blaine Gibson, from Carmel, California, having already travelled to Ethiopia in search of the Lost Ark of the Covenant, has devoted much of the past three years to scouring foreign beaches for MH370 debris.

Blaine Gibson with suspected MH370 debris that he found on a beach in Madagascar (Blaine Alan Gibson)

Such independent investigators may soon be joined by others, with more deeply personal motives.

Despairing of the suspension of the official search, relatives of the MH370 passengers last month revealed they would be seeking to raise $15m (£12m) to fund their own hunt for the missing plane.

“We do not envisage such a search replacing the government or in any way releasing the governments involved in the search thus far from their obligations,” wrote Mr Narendran, explaining that the relatives were acting out of “a sense of anger, betrayal and chaos”.

If the official search did not resume, he said, “We will work to elicit fund commitments from world governments, corporations, high net-worth individuals and the travelling public.”

“This is not likely to be easy,” he admitted.

But what choice did he and the other relatives have?

“Like most family members of passengers,” wrote Mr Narendran, “I have survived. It is not to say that the living process has been repaired and normal has been restored.

“While I presume that lives of passengers have ended, memories are strong, vivid and make the process of looking ahead painfully difficult.

“It is made worse by the knowledge that we actually don’t know very much more than what we gathered on 8 March 2014... that a plane had just disappeared.”