The Disappearance of Flight MH370 & Other Puzzling Cases of Vanishing Aircraft

Over the last couple of weeks international attention has been ensnared by the mysterious disappearance of Malaysia Airlines Flight MH370. Since the plane vanished on March 8 there have been hourly media reports on the collective search efforts of 26 countries to uncover the fate of the airliner and its 239 missing passengers and crew members.

Now more than two weeks into the search and many theories have surfaced on what may have happened to MH370. However the same can't be said for evidence, as any clue that can shed light on the plane's location has yet to been found.

Despite the Malaysian Government recently conceding that the plane probably crashed in the South Indian Ocean, for now the search goes on.

Meanwhile the grief felt by the friends and family of those aboard the airliner is fueled by the lack of closure over the fate of their colleagues and loved ones. This is only made worse by the search effort not having turned up any clue or piece of information so far, leaving many people baffled as to how such a plane could seemingly vanish without a trace. .

This however is not the first time such an event has occurred.

This hub briefly explores the different theories that have been presented on the missing airliner before covering several similar cases of equally puzzling aircraft disappearances.

Little information has been revealed so far and theories and ideas on what may have happened continue to shift and contradict one another. According to the Sydney Morning Herald, daily press briefings were largely used by investigators as a method to refute misinformation, rumors and speculation, rather than providing new details on the mystery.

The truth is that we will never truly know what's happened to MH370 until the plane is found.

What is known for certain is that MH370 departed from Malaysia's International Airport at 00:41 MYT on March 8 and disappeared en route to China's Beijing Capital International Airport. Fifteen different nationalities made up the passenger list, with 152 people coming from China. Other passengers were citizens of Malaysia, Indonesia, Australia, India, America, France, Canada, Ukraine, New Zealand, Italy, Holland, Russia, Taiwan and Austria.

Prior to the airliner's disappearance instruments used to track and communicate with the plane were switched off. These include the Aircraft Communications Addressing and Reporting System (ACARS) and the transponder.

The ACARS is a service that runs health checks and diagnostics on an aircraft and reports this information to computers on the ground. It allows planes to receive an transmit information and messages from the ground by radio or digital signals via satellites.

While primary raider can track any aircraft in the sky it remains unidentified without the use of a secondary radar, such as a transponder, which sends electronic messages known as ‘‘squawks’’ to radar systems about the plane’s altitude, flight number, speed and the direction in which it is heading.

Primary radar is used most often for military air defense, while civil aviation relyies more on secondary radar.

The last communication with the plane occurred at 1:19am with co-pilot Fariq Abdul Hamid, whose final words were an informal "all right, good night". He gave no indication that anything was wrong on board the plane.

According to Malaysian officials the ACARS sent its last update at 1:07AM. It was scheduled to send further updates every 30 minutes, but failed to transmit data at 1:37AM. This suggests that the cause of MH370's disappearance may have taken place during that 30 minute period.

At 1:21AM the plane's transponder was also disabled.

Since then there have been several sightings by satellite and and aircraft of possible plane debris. These include an oil slick off the coast of Malaysia and objects floating in the South China Sea between Vietnam and Malaysia (south-east of the plane's flight path), as well as a possible door and life raft near Vietnam and several items in the southern Indian Ocean around 2,500 km (1,500 miles) southwest of Perth Australia.

After some investigation, none of these sightings were found to relate to MH370.

Currently search efforts are determined to locate MH370's flight recorders, which will have retained two hours of recordings that may provide critical information on the events that transpired on the plane.

If the plane crashed, a locator beacon inside the black box should have switched on automatically, transmitting a sonar signal. The beacon, as well as a second emergency locator transmitter that activates on impact and remains active for around 24 hours, have not been detected.

While flight recorders function throughout the flight, the black box only retains two hours of recordings. The battery life for the locator beacon on MH370 will last only 30 days. If the black box hasn't been located by April 7-8, then search teams and investigators may have an even harder time finding the plane and piecing together what happened on board.

The black box for Air France 447, which was found two years after it crashed into the Atlantic Ocean in 2009, provided a valuable insight into the aircraft's final moments.

The Plane Went Down in the Southern Indian Ocean

The most recent update took place on March 24, 10:15 Malaysia Time. Officials from Malaysia Airlines released an official media statement that explained that even though search efforts were to continue, government officials assumed that the flight of MH370 "ended in the southern Indian Ocean" with no survivors.

This statement was made following British satellite analysis that showed that the plane's last known location was in the middle of the Indian Ocean, west of Perth, Australia. Malaysian Prime Minister Najib Razak advised that it was a remote location, without any nearby landing sites in the vicinity.

Terror Attack

Initially many believed that MH370 may have fallen victim to a terrorist attack. As the majority of passengers were Chinese, some suggested that the plane may have been targeted by Uygher separatists who are fighting for an independent Xingjiang, an autonomous province in China's far-west. In early March the group carried out an attack at a train station in the southwestern city of Kunming, where 29 commuters were stabbed to death and 143 wounded.

Shortly after the incident a group calling themselves 'The Chinese Martyr's Brigade', took credit for an attack on the plane sending emails to journalists across China with the message "You kill one of our clan, we will kill 100 of you as pay back.”

The group had never been heard of previously and their email didn't include any new details, instead referring to facts that were already common knowledge. Their claim has been dismissed by Malaysian officials, including acting transport minister Datuk Seri Hishammuddin Hussein, as a probable opportunistic hoax intended to exploit the situation to increase ethnic tension between Uyghers and Han Chinese.

The international director of the global terrorism research centre at Monash University in Australia, Greg Barton, says that the reason why no credible claims have come from known terrorist groups may be due to the operation only being partially successful. Barton suggests that operatives may have successfully taken control of the plane but failed in their ultimate objective, which might have been a collision with a key target such as the Petronas Towers in Kuala Lumpur.

A recent background check of those on board also failed to uncover any links between passengers and terrorist organisations.

Investigators have not ruled out the possibility of terrorism, but are unable to find substantial evidence that terrorists were on board, making them conclude that it probably wasn't the cause for the plane's disappearance.

Checked On The Flight Without Boarding The Plane (Debunked)

Shortly after the plain disappeared officials reported that around four to five passengers had checked on to the flight but hadn't actually boarded the plane, leading some to suspect that a terror plot may have been involved and that something may have been planted in their luggage.

This was later found to be untrue.

Malaysia Airlines later confirmed that four individuals had booked a ticket for the flight but never checked in. Their seats were given to stand-by passengers.

The Plane Changed Direction

After air traffic control lost contact with MH370, primary military radar did detect an aircraft change course and travel 200 miles northwest of Penang Island, heading west towards the Andaman Sea rather than following MH370's intended flight path over the Gulf of Thailand. Malaysia's military radar doesn't stretch beyond this point and they reportedly requested radar data from neighboring countries.

It's not known whether the unidentified aircraft was the missing airliner, but search efforts were extended to the Strait of Malacca as well as the South China Sea where the plane was detected on civilian radar before vanishing.

Like many details of the plane's disappearance, this theory has also been distorted somewhat by contradicting arguments and information. For example General Tan Sri Dato'Sri Rozali Bin Daud, the chief of the Royal Malaysian Air Force, has denied that the Malaysian officials ever confirmed that the plane changed its flight path and that information was the product of misreporting from the media.

Piracy or Hijacking

With search efforts continuing over a week without finding any sign of the airplane, a growing theory is that the plane never crashed and was instead hijacked by some sort of pirates who took control and landed the plane undetected. This may have been carried out for economic gain.

Supporting this theory is the common belief that the transponders and ACARS seem to have been deliberately disabled. This could be done from the plane's avionic's bay or by pulling a circuit breaker or switching these systems off from the flight deck. The shift in direction by an unidentified aircraft that was detected by military radar also indicates that the plane is following a commonly used navigational route towards Europe and the Middle East.

According to investigators hijacking the plane would have required some knowledge of navigational way points and the ability to either take manual control of the jet or program the course into the auto-pilot.

Military radar also detected some erratic movement from the plane in which it changed altitude and direction several times, supporting the idea that someone else may have taken control of the plane or that there had been a struggle in the cockpit between the pilots and hijackers. Before vanishing from radar, the plane was recorded flying at an altitude of 45,000ft, which is around 2,000ft above what Boeing says is its maximum recommended height, before descending to 23,000ft.

Since 2000 there have only been 18 hijacks or attempted hijacks of large passenger aircraft. Seven of these were by passengers wanting to get to a destination to seek asylum, one was criminally motivated to steal the cargo, six were by mentally ill persons, and four were politically motivated (counting September 11 as one incident),

The Plane Flew on For Hours

A common theory is that an antenna on top of the plane that's associated with ACARS, but can't be disabled by switching of that system, continued to "ping" or communicate with satellites for hours after after the plane vanished from radar. This doesn't mean that it was transmitting data or even giving away its position, only that satellites on the Inmarsat network had continued to pick up "routine, automated signals" from MH370 hours after it had gone missing.

Automated attempts to open channels and allow communication between the aircraft's systems and the satellites (a process some refer to as a "digital handshake") were unsuccessful due to Malaysia Airlines not having subscribed to that particular service.

Satellites ping communication system approximately every hour. In the case of MH370, six pings were registered on the Inmarsat satellite network, with the last one taking place around 8:11 AM.

As the plane's antenna requires power to communicate with satellites, the fact that it was detected is an indication that the plane was still in the air and perhaps traveled for an additional six to seven hours.

Inmarsat analysts found that satellite contact with the missing plane couldn't pinpoint its location, but they theorized that the plane may have traveled along a northern corridor that stretches from Kazakhstan and Turkmenistan to northern Thailand; or taken a southern corridor that runs from Indonesia to the southern Indian ocean.

Search efforts were eventually extended to these areas, after Malaysia Airlines and the Government initially contested suggestions that a transmitter on the plane had continued to give off a signal for hours after disappearing.

Pilot Involvement

As authorities believe that the transponder and ACARS were switched of deliberately, some have suspected whether one or both of the pilots have been involved or coerced into rerouting the plane. This theory is further supported by the technical knowledge required to change the plane's flight path.

Both the pilots have been investigated and their residences raided, though no incriminating details having been reported on either individual and nothing has been found that suggests that the pilots were anything other than upstanding professionals.

However there has been some speculation on a possible political motive by pilot, Zaharie Ahmad Shah who is distantly related to the daughter-in-law of opposition leader Anwar Ibrahim. Shah is known to be a supporter of human rights groups and causes, including campaigns for increased media freedom in Malaysia. He is also a close friend of Sivarasa Rasiah, vice-president of the People's Justice Party, of which Shah is also a member.

Anwar Ibrahim, as well as other friends and associates, have rejected allegations that Shah would have hijacked a plane and risked over 200 lives over his socio-political beliefs.

Mechanical Failure

Around the time that the plane vanished an oil rig worker off the coast of Vietnam claims to have seen something burning up in the sky. This has led some to suggest that the plane may have experienced some sort of mechanical or technical rpbolems, such as a power failure. Though if such a scenario occurred it would have probably been resolved by back up generators.

Mechanical and systems failures have been known to cause air disasters in the past. An example includes TWA flight 800, which exploded over the Atlantic in 1996, killing all 230 people on board. Investigators ultimately blamed the blast on an electrical short circuit near a fuel tank on the Boeing 747.

According to A330 pilot Captain Bill Palmer, who had previously written about the plane crash of Air France Flight 447, the most likely cause to MH370's disappearance would have been a system's failure, possibly caused by a fire.

Pilot Error

While the pilot and co-pilot were highly skilled, a consistent theory is that one of them may have made a mistake that had dire consequences, possibly resulting in the plane crashing.

Pilot error is always a risk and has resulted in a number of incidents in recent years. Recent examples include the Airblue Flight 202 in 2010, which crashed into Margalla Hills in Pakistan due to a number of factors including the cabin crew's lack of experience and pilot error; Air France Flight 447, which crashed into the Pacific Ocean after a series of mistakes made by the crew.

There has been some media scrutiny into co-pilot Fariq Abdul Hamid's alleged history of breaking Malaysia Airlines' policy of inviting passengers into the cockpit. In 2011 he allegedly invited several young female tourists to join him and his co-pilot in the cockpit, where they reportedly paid little attention to flight controls and instead chat, smoked, took photos and entertained the women.

The Plane Flew Under the Radar

In mid-March investigators expressed a theory that involved the missing plane evading radar by dropping to altitudes as low as 1524 metres (5000 feet), in a flying technique known as "terrain masking". This is a method used by military pilots on stealth flights.

As the plane is believed to have remained in the air for several hours after it vanished from radar, MH370 could have passed over two additional countries besides Malaysia, although there's uncertainty as to which ones. By following commercial routes the plane may not have raised the suspicion of personnel monitoring primary military radar in the countries that it overflew.

According to investigators who ever was controlling the aircraft had "a solid knowledge of avionics and navigation and left a clean track" and that the aircraft may have "hugged the terrain in some areas, that are mountainous to avoid radar detection."

MH370 Shadowed Another Plane

Aviation blogger Keith Ledgerwood has suggested that the plane could have hidden itself from radar by flying in the shadow of Singaporean airliner SIA68, making the two planes effectively appear as one entity on civilian radar.

With the plane's transponder disabled, MH370 would have been able to travel through Indian and Afghanistan airspace undetected and without SIA68 ever knowing that they were there. Some time during the flight, the plane may have broken away from the Singaporean airliner and headed for Xinjiang, Kyrgyzstan, or Turkmenistan.

Professor Hugh Griffiths, a radar expert at University College London, admitted that the Ledgerwood's explanation was feasible, but primary military radar should have been able to recognize that there were two objects, not just one.

There was a Fire on Board

US authorities have suggested that the plane may have caught on fire from carrying a heavy load of lithium batteries, which are known to overheat and even burn their surroundings. Though batteries have been attributed as the cause for previous cargo-plane crashes, some have pointed out that this theory is inconsistent with speculation that the plane may flown for hours after it vanished.

According to former pilot Christopher Goodfellow, the most logical explanation is that a mechanical malfunction may have sparked a blaze or electrical fire that disabled the transponder and ACARS.

Goodfellow says that a sharp turn made by the plane during its first hour of flight and noticed on military radar, may have been an attempt by the pilots to reach the nearest airstrip on Palau Langkawi. Passengers and crew may have fallen unconscious due to the smoke and the plane may have flown another 6 hours on auto-pilot before crashing.

Cyber-Hijacking

According to British anti-terrorist expert Dr Sally Leivesley the plane may have been subject to a cyber-hijacking, which could influence the aircraft's speed, altitude and direction by sending radio signals to its flight management system. The plane could then be remotely controlled to either land or crash.

According to Leivesley malicious codes could be introduced into the aircraft's system and triggered with a mobile phone or a USB. This may allow access and control over certain functions by remotely inputting instructions and initiating a series of processes.

Mid-Air Disintegration

On March 9 Reuters reported that officials investigating the disappearance were narrowing on the conclusion that the plane may have disintegrated at around 35,000 feet, which would explain why no debris has been found. Such a situation may have been caused by an explosion or mechanical failure.

This information was obtained by Reuters from an undisclosed senior source, who insisted on anonymity because he had not been authorized to speak publicly on the investigation. According to the source the closest parallels include the destruction of an Air India Jetliner in 1985 and the Lockerbie air disaster in 1988. Both planes had a bomb on board that exploded while cruising at around 31,000 feet.

Terrorists Where Using Stolen Passports (Debunked)

Initially there was much speculation on whether the plane's disappearance may have been caused by two passengers who boarded with stolen Italian and Austrian passports. Despite already having being reported lost in Thailand in 2012 an 2013 and added to Interpol's Stolen and Lost Travel Documents (SLTD) database, there had been no checks on the passports since they were reported stolen. As a result Interpol is unable to determine whether they had been used prior to MH370.

The two men were later identified as Pouria Nour Mohammad, 19, and Seyed Mohammed Rezar Delawar, 29, both Iranian Asylum Seekers.

Contrary to previous beliefs that those using the passports may have been agents belonging to the Uyghurs in China, neither man has been linked to any terrorist group. Instead authorities believe that they were hoping to immigrate to Europe and were on their way to Frankfurt, Germany to meet up with Mohammed's mother.

Identification of the two men has cast greater doubt on the possible involvement of terrorism.

Pilot Suicide

According to Mike Glynn, a committee member of the Australian and International Pilots Association, the most likely explanation for the plane's disappearance may be a suicide attempt by one of the two pilots. Such a hypothesis may explain why no sign of the plane has yet been found, as the plane would remain relatively intact, with little-to-no debris, if it dived into the ocean.

Such an occurrence isn't unheard of, as The Aviation Safety Network believes that pilot suicide attempts may have already been the cause for at least eight plane crashes since 1976. Examples include Mozambican Airlines flight TM470 in November 2013; Egypt Air Flight in 1999; and Silk Air Flight 185 in 1997 which are all believed to have been crashed deliberately by the pilot.

Decompression

Another popular theory suggests that there was rapid decompression in the plane's cabin that rendered crew and passengers unconscious after the pilots turned the plane aroundto return to Malaysia. The plane may have remained in the air until if ran out fuel. If such an incident were to occur the crew should have been quick to don their own oxygen masks to ensure that they maintained control of the aircraft.

Some suggest that an explosion may have occurred on the flight deck crew's emergency oxygen supply, in a bay under the floor which also includes communications systems. This would have disabled the plane's communications ability and could have rendered all those on board unconscious. Such a scenario occurred in 2008 where an emergency oxygen tank exploded on a Qantas 747, blasting a hole in the fuselage, decompression, and an emergency landing to take place.

Another theory suggests that who ever was controlling the plane may have deliberately depressurized the cabin to kill the passengers and stop them from using their phones. The oxygen masks that are automatically deployed in such a circumstance would run out after 12-15 minutes, resulting in passengers being deprived of air and falling unconscious.

The Plane Fell Victim to a Shoe Bomber

Comments from Saajid Badat, a former Al-Qaeda operative, while testifying at the trial Sulaiman Abu Ghaith received some media attention in mid-March as a possible explanation of what happened aboard the airliner.

In 2001 Badat was recruited with the infamous Richard Reid to board a plane and detonate explosives that had been concealed in their footwear. Reid's attempt to destroy an American plane failed, while Badat had a change of heart and decided not to go through with his plans of blowing up a British aircraft.

While Badat kept one of his explosive shoes at home, he claimed that he gave the other to a group of Malaysian jihadists who were planning to carry out a similar act aboard an aircraft.

Terror expert Rohan Gunaratna told The Australian that though British security experts found Badat's claim "credible", this was most likely irrelevant to MH370's disappearance. Gunaratna explained that the terrorist plot mentioned by Badat was a decade old and the shoe bomb was intercepted by US authorities in 2004 before it could be used.

The Plane has Landed and is Hidden

The lack of debris from the plane has led some to theorize that the plane may have landed without being detected and hidden in a remote area. If this theory is true, then there's a chance that the passengers and crew are still alive.

A number of people have suggested that the plane may have landed in the Andaman Islands, Kazakhstan, Pakistan or the Taklamakan Desert in China.

However the size of the Boeing 777 and the amount of space needed for it to land, including a 10,000 foot runway, make such a feat difficult and some what unlikely.

Cover Ups & Conspiracy Theories

With search efforts failing to find any clues on the plane's fate and the Malaysian Government's somewhat awkward handling of the search efforts, some people have begun questioning whether the Malaysian government knows more than they're letting on and are unwilling to share certain information, possibly due to a perceived security risk.

Criticism of Malaysia's involvement include delays of the search efforts and in sharing information as well as releasing muddled and contradicting details that increased confusion.

Families of those on board MH370 have been particularly vocal in their criticism of how Malaysian officials have handled the search efforts, with relatives of some of the Chinese passengers interrupting a press conference last week in Kuala Lumpur in an attempt to get more information from the government.

Following the Prime Minister's speech that the plane is considered lost with the most likely scenario being a crash in the Indian Ocean, many of the victim's family still remain skeptical after weeks of theories, counter-theories and confused information. Some believe that the government is holding the plane or has covered-up its real fate for unknown reasons, with over 100 relatives signing a petition demanding information and assistance from the Malaysian government.

In the days following the plane's disappearance, relatives claim that they were able to ring the mobile phones of their loved ones, indicating that they were active and connected to the network, providing investigators with a new possible tactic to locate the plane by using GPS tracking to find the phones. Others claim that on QQ, an instant messaging service, missing passengers' profiles were displayed as active and online.

There have also been a number of conspiracy theories including speculation that Iran has captured the plane and is retrofitting it with a nuclear device so as to turn it into a nuclear weapon in disguise. Other random suggestions on the plane's disappearance involve the testing of experimental cloaking technology and of coarse the obligatory alien abduction theory that's become essential for any list of conspiracies.

Amelia Earhart

Many media reports have drawn comparisons between MH370 and the disappearance of the legendary American aviator Amelia Earhart, the first woman to fly across the Atlantic as a passenger in 1928 and solo in 1932, as well as the first person to fly over both the Pacific and Atlantic.

In 1937 Earhart and her navigator, Fred Noonan, set out on an around-the-world voyage in a Lockheed Electra L-10E plane. They traveled 22,000 miles to Lae, Guinea but then vanished en route to Howland Island, southwest of Honolulu. The USCGC Itasca received their last transmission on July 7 1937 at around 7:20 before the plane was never heard from or seen again.

Search efforts were extensive and involved 66 aircraft and nine ships at an approximate cost of $4 million as authorized by President Franklin D Roosevelt. Earhart's husband, publisher George P. Putnam financed additional search efforts. Nothing of The Electra or the two aviators was ever discovered.

Earhart was declared legally dead in absentia in January 1939. Noonan was declared the previous year. No sign of either person or their plane has ever been found.

Many theories exist regarding what happened to the plane, including that she was that she was lost and out of gas; that the plane crashed into the ocean; or that the government has covered up the incident by keeping critical information from the public on the fate of Earhart and Noonan. There a range of theories involving Japan, including that she was captured by the Japanese during World War II and then executed; that her flight was an elaborate scheme to spy on the Japanese; that she became a radio propagandist known as 'The Tokyo Rose'.

Other theories suggest that she survived her plane crash and lived out the rest of her life in New Jersey under a different name; that she worked as a nurse in Guadalcanal; or that she and Noonan landed on the uninhabited Gardner Island, where they eventually died.

Flying Tiger Line Flight 739

During the Vietnam War on March 16, 1962 Flying Tiger Line Flight 739 disappeared over the Western Pacific Ocean while en route from Andersen Air Force Base to Clark Air Base in the Philippines. The plane was carrying 107 people including 93 US Army Rangers, 3 South Vietnamese soldiers and 11 crew members. Despite extensive search efforts that covered around 200,000 square miles, no sign of the plane was ever found.

The Bermuda Triangle

The Bermuda Triangle (also known as the 'Devil's Triangle') is an infamous stretch of ocean that covers a 500,000-square mile area between Puerto Rico, Miami and Bermuda. Scores of planes and ships travelling through this patch of ocean have mysteriously vanished without a trace and remain a mystery to today.

According to Discovery.com, over the last 70 years more than 100 aircraft have vanished in the Bermuda Triangle and more than 1,100 lives have been taken in the last decade.

Many theories exist on the Bermuda Triangle, with suggestions that the disappearance of planes and ships may have been caused by human error, erratic compass variations, violent weather and methane hydrates capable of reducing water density and stalling the engines of any plane. Other's suggest more random theories involving alien abductions, the lost city of Atlantis, government testing and time vortexes.

It remains one of the world's greatest mystery spots.

Boeing 727-223, N844AA

On May 25 2003 Boeing 727-223, tail number N844AA, was stolen from Quatro de Fevereiro Airport. It entered the run way erratically and without clearance. There was no communication between the tower and the plane, which also had its lights off and transponder disabled. The plane took off to the southwest, and headed out over the Atlantic Ocean.

It's believed that certified flight engineer Ben Charles Padilla was on board, with recently hired assistant, John Mikel Mutantu. Neither the plane nor the two men were ever seen again and their destination and present day location remain a mystery.

There's also no obvious reason as to why the plane was stolen, though some theorized that it may have been part of an attempted terrorism plot or that the owners arranged its theft for insurance purposes.

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• 'Malaysia flight MH370: Theories swirl around disappearance', BBC, March 14 2014.
• 'Oil rig worker says he saw Malaysia Airlines Flight MH370 burst into flames', news.com.au, March 13 2014.
• Statsna, K. 'How could Malaysia Airlines Flight MH370 go off the radar?', CBC News, March 14 2014.
• 'Theories that missing flight MH370 is the victim of piracy gain momentum', March 15 2014.