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 because of a mechanical malfunction. In a thorough investigation, investigators always look for potential mechanical deficiencies in the type of airplane under investigation. They look for any deficiency that could pose a risk to the airplane type (in this case, the entire fleet of B777s). In any investigation, the search for such deficiencies can lead to safety improvements, even if they find a deficiency that they are unable to connect directly to the event.

To investigate the likelihood of a mechanical malfunction as the lead event in the disappearance of MH370, we must follow a standard investigation process. As has been stated previously, there is a difference between finding a potential safety deficiency (something that theoretically could happen), and connecting that potential deficiency to the actual sequence of events that led to the loss of the airplane.

We can refer back to our ‘Battleship’ grid with all the known facts listed one underneath another in the far left hand side of the grid, and the potential lead events, or potential scenarios, across the top. You will recall that only the column with the true and actual lead event at the top will allow a checkmark (✔) in every box.

The first known anomaly with MH370 was the disappearance of the transponder signal. At the same time, the airplane started its turn to reverse course. Our investigation to look for a potential mechanical malfunction lead event must find a way to connect the mechanical failure directly to these first anomalies.

It is easy to imagine how a mechanical or electrical malfunction could have caused the transponder signal to be disrupted. For example, hypothetically, there could have been an electrical short circuit, or simply a failure in one of the components supporting the operation of the transponder.

It is not so easy in this hypothetical scenario to imagine why the pilots were unable to restore the transponder signal. The B777 has a significant amount of redundancy in its transponder system. The airplane has more than one transponder, and there are numerous paths for electrical power to reach each transponder.

To continue our investigation process, we can look past the first known anomaly to the next known events, and examine them in the context of the hypothetical mechanical or electrical malfunction. We know that after the transponder signal stopped, the airplane remained flyable. We know this because the airplane continued to fly for several more hours.

We know that regardless of the nature of the hypothetical malfunction, the pilots were not completely disabled. We know this because they not only reacted to the transponder malfunction by reversing course; they reprogrammed the navigation system to execute several turns.

With this hypothetical mechanical or electrical malfunction, we also have to account for the fact that the pilots were still functioning at the end of the flight, where there was an intentional and controlled ditching. For any hypothetical mechanical or electrical malfunction to be valid, it must be able to be connected not only to the first known anomaly, but also to each of the subsequent events, all the way to the end of the flight.

The proponents of a mechanical or electrical malfunction have theorized that the same (initial) malfunction that caused the transponder signal to disappear also caused the airplane to depressurize. The representative storyline goes like this – the malfunction occurs – the first reaction by the pilots was to turn the airplane around – the performance of the pilots was degraded by hypoxia – they mistakenly reprogrammed the flight management system to follow the new track – and then the pilots succumbed to hypoxia.

This sequence, of course, would lead to MH370 being an unpiloted airplane. We have proof that the unpiloted airplane theory is not correct. The fact that MH370 was under the full control of a pilot at the end of its flight puts to rest any potential that the entire sequence of events started with a mechanical or electrical failure.

In my view, there is no need to go through any more of the numerous other theories involving a mechanical or electrical fault as the lead event in the disappearance of MH370. The storyline for each of these theories includes the pilots being disabled, and there being an unpiloted airplane, and we know that is not true.


The Theory of an Onboard Fire

The Theory of a Passenger Hijacking

The Theory of an Electronic Hijacking

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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