Various scenarios have been put forth as potential explanations for the disappearance of MH370. As I have shown in my book, there is only one that is consistent with all of the known facts. To learn about the methodology that can be used to examine and assess any proposed scenario, read this article or listen to the audio version below.

Some people support the theory that MH370 disappeared after a passenger or passengers on board hijacked it. Once they gained control, they dictated and controlled each subsequent event, all the way to the end of the flight.

The case for a passenger hijacking is very weak, and the arguments against it are strong. However, there is no specific evidence to unequivocally reject it. Therefore, to investigate it we must follow a standard investigation process. There are at least three different hijacking scenarios that have support from some MH370 investigation enthusiasts.

The first is a scenario where a passenger or passengers onboard MH370 hijack the airplane by gaining access to the cockpit.

The second scenario involves one or more passengers gaining access to the airplane’s onboard flight computers, which are located in the electronics and equipment bay. The compartment housing the electronics and equipment can be accessed from inside the passenger cabin through a hatch door in the floor aft of the cockpit. This scenario suggests that hijackers entered the compartment, and used sophisticated electronic equipment they had smuggled on board to take control of the airplane.

The third scenario involves remote hacking into the airplane. The perpetrators remotely hacked into the airplane’s flight management systems, thereby controlling and navigating the airplane remotely.

Let us first look at the possibility of a hijacking by a passenger or passengers who were on the airplane, and gained access to the cockpit.

Passenger doors on airline airplanes are exceptionally robust. Once the cockpit door is closed for flight, the only way the door can be opened is if a pilot unlocks it from inside the cockpit.

The first thing to be looked at when assessing a potential passenger hijacking is timing. We must show a direct link between our “cause” (in this case the hijacker), and the first known anomaly (the disappearance of the transponder signal). Remember that it was less than two minutes from when the pilot made his final radio transmission until the transponder signal disappeared. In fact, the first transponder anomaly occurred only one minute and six seconds after the pilot’s final radio transmission. We must assess the likelihood of a hijacker being able to access the cockpit, and disable the transponder, in that short of a timeframe.

Another factor in this passenger hijacking theory is that the hijacker would have to be very knowledgeable about airplane operations, and have very specific knowledge about operating a B777. The hijacker would have to know that disabling the transponder would make the airplane disappear from radar. Also, the hijacker would have to know how to keep the pilots from taking subtle actions that would alert air traffic control about the hijacking.

The investigation authorities claimed that they conducted background checks on everyone on board MH370. They contend that no one on board had a background that would give them specific knowledge about airplane operations. If that is true, then the only two people on board MH370 who were capable of operating and flying the airplane were the two pilots. Therefore, in this passenger-hijacking scenario, we must assume that the hijacker forced the MH370 pilots to keep flying the airplane, and to follow his orders.

Let us return to how this hijacker could gain access to the cockpit. We can envision how the cockpit door might have been opened momentarily. Perhaps a pilot opened it to allow access by a flight attendant. Perhaps one of the pilots had to leave the cockpit to use the washroom. Remember the timing – the hijacker would have had only about one minute to gain access through the cockpit door, and then to gain control of the airplane, and then to have the pilots shut down the transponder, and then to have the pilots start a turn to reverse course.

Because of the timing, you would have to assume that when the cockpit door was opened, the hijacker was nearby, and ready to attack. Only people in the first class section of the airplane would be in a position to have quick access to the cockpit door area. The hijacker would have to be nearby, and watching for that door to be opened. Most certainly, the cockpit door would not have been opened if any unexpected passenger were lurking nearby.

In this passenger hijack scenario, here is what would have to happen within a timeframe of something less than one minute. The hijacker would have to force his way into the cockpit. Then the hijacker would have to gain full control over both pilots. Then the hijacker would have to order the pilots to disable the transponder. Then the pilots would have to comply. At the same time, the hijacker would have to order the pilots to immediately start a turn to reverse course, and the pilots would have to comply.

Remember that in this scenario, these activities took place at the exact location where there was a handoff between air traffic control agencies. At this location, air traffic control monitoring of the airplane was at a minimum. It would be a tremendous coincidence if a ready and waiting hijacker were fortunate enough to have the cockpit door open at that most suitable location.

You would have to assume that the hijacker knew enough about airplane systems to know that the transponder is the electronic link that allows air traffic control to see the airplane on radar. You would have to assume that the hijacker knew how to ensure that the pilots actually complied with his request, and switched the transponder off. You have to assume that the pilots complied with the hijacker’s request, and they did so because they knew that he would recognize it if they simply switched to another transponder, or otherwise failed to comply. The pilots would know of many ways to send information from the airplane to ATC that would be unknown to an unsophisticated hijacker. Nevertheless, nothing more was heard from MH370.

You would have to assume that the hijacker also knew specifically to order the pilots to disable the ACARS communications system. Remember that in the factual sequence of events, the ACARS failed to send a scheduled routine position report that should have been sent about 16 minutes after the transponder signal disappeared. In this passenger-hijacking scenario, we can assume that the hijacker ordered the pilots to disable the ACARS, in addition to disabling the transponder.

Disabling the ACARS in the cockpit is not something that pilots would ordinarily or routinely do. There is no reason to do so. There is not one specific switch to turn the ACARS off. To disable ACARS requires very specific knowledge, and more than one action by the pilot. This suggests that if there was a passenger-hijacker dictating the events, that hijacker was someone who had sophisticated knowledge about the operations of a B777, and in particular about the ACARS.

From the factual sequence of events, we know that about one hour after the ACARS first missed its expected routine update, it came back online. However, it did not return to full functioning, in that it still failed to transmit its expected routine reports. Once it is disabled, there is no way for the disabled ACARS to come back online unless someone turns it back on. Again, turning the ACARS back on cannot be done by simply selecting an ON switch; it requires specific and sophisticated knowledge, and more than one action. There is no reasonable explanation for why a hijacker would order the pilots to turn the ACARS off, and then allow them to go through the process of turning it back on.

We then must assume that the hijacker dictated the specific route that the airplane followed, starting with the initial turn to reverse course, and including its other turns, and its eventual long flight to the southern Indian Ocean. We then must assume that the hijacker ordered the pilots to carry out a controlled ditching on the ocean surface, and we must assume that the pilots complied.

This hijack theory cannot be dismissed by definitive and unequivocal evidence. Each element of it is theoretically possible. However, when assessed from start to finish, it is highly unlikely that all of the elements described above could come together without the pilots taking some action to intervene.

To get an even greater appreciation for how unlikely a passenger-hijacking scenario is, we need only look at how much less complicated it would be for a pilot to take the actions instead of a hijacker.

It is not realistic to propose that a hijacker had the ability to direct the pilot to accurately fly any specific course, especially one designed to avoid military radars. Even if you accept that premise, it is not realistic to propose that in the dark of night a hijacker would be able to follow the airplane’s progress to ensure it was going to where he had directed the pilots to take it.

It would be easy for the pilots to confuse the hijacker, and take the airplane in a different direction. If they were hijacked, the pilots would want to attract attention from ATC. They would want to fly over land, and in particular, would want to avoid flying so far from land that they would have no option but to end up in the ocean.

In this proposed passenger-hijacking scenario, the pilots would still be flying the airplane. The pilots would most assuredly take action once they recognized that without their intervention the airplane would end up in the ocean. They would not sit idly by and allow the airplane to fly for hours out to sea. The pilots would have options.

One option would be to cause the airplane to suddenly depressurize. They could do this with a single switch selection. Rapid decompression would allow an opportunity to neutralize the hijacker. Given the pilots’ familiarity with the airplane and the cockpit, and the hijacker’s lack of familiarity, the pilots would have a distinct advantage. They would be able to get themselves on oxygen, and continue to function. Meanwhile, in the confusion, the hijacker would quickly succumb to hypoxic symptoms.

Of course, this depressurization would also affect the passengers, but once the hijacker was neutralized the pilots could quickly restore the pressurization and descend the airplane to get oxygen levels back to where hypoxia would no longer be an issue.

Another option for the pilots would be to disable the cockpit lighting, and manually fly the airplane into a condition with high G-forces, or negative G-forces. Again, the pilots would have a distinct advantage in the darkness and confusion. This could be done in combination with depressurization.

I will not attempt to list all of the options that might be available to pilots in this type of passenger hijacking scenario. There are two things that are certain. One is that any pilot, including the pilots of MH370, would take whatever actions were available and necessary to avoid flying the airplane to an unavoidable fatal outcome. The second is that if MH370 were a passenger hijacking, it would not have ended with the pilots conducting a controlled ditching in a remote part of the southern Indian Ocean.


The Theory of an Onboard Fire

The Theory of an Electronic Hijacking

The Theory of a Mechanical or Electrical Malfunction

The Theory of a Bomb, or Military Action

Book cover of MH370: Mystery Solved by Larry Vance


This book, by a veteran air crash investigator, finally explains what really happened to Malaysia Airlines Flight 370

On March 8th, 2014, Malaysia Airlines Flight 370, with 239 people on board, disappeared into the dark of the night, never to be heard from again. The disappearance of MH370 has been described as the “greatest mystery in the history of aviation”.

Despite the efforts of an international investigation team, and millions of dollars spent searching the ocean bottom, the wreckage was not found.

This book explains why.

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