What causes planes to crash or go missing?

According to some statistics, the likelihood of a plane crashing ranges from as unlikely as one in 5.4 million to one in 11 million. This puts the likelihood of death from an air disaster behind terrorism, food poisioning and even falling out of bed.

So what are the unlikely causes of when things do go wrong?

Human vs mechanical error

According to Boeing, one of the world's largest aircraft manafacturers, mechanical errors accounted for around 80 percent of accidents in the early days of flight, with human error responsible for the remaining 20 percent. By the early 2000s, however, improved technology meant that this trend had reversed, with accidents related to aviation equipment accounting for only 20 percent of incidents.

Today, more than half of plane crashes are caused by errors related to pilots, air traffic control crews and cabin staff.

This is all the more understandable when the potential variables for disaster are considered. While many accidents have occurred due to misjudgements about weather and initially minor mechanical problems, there are other factors that can affect a pilot's performance during flight.

In 1976, a South African Airways plane crashed after the pilot suffered a heart attack, and a flight from Tokyo in 1987 ended in disaster when a pilot suffering from mental issues put the plane's engines into reverse mid-flight.

Crashes have also been caused by pilot fatigue or the working cultures of the airlines. When a Korean Air cargo plane crashed in 1999 in England, an investigation into the causes revealed that it may have been due to a culture of deference within the flight crew's heirarchy of command.

	Improvements to technology have increased flight safety [Getty]

 

A misjudgment by the pilot was not corrected by his first officer, likely out of respect for his experience, and as a result the plane crashed and killed all four crew members.

Adding to the list of human errors are simple but costly mistakes. A shocking example in 1972 saw Eastern Airline flight 401 crash into the Florida Everglades, killing 101 passengers and crew.

The crash was the result of all three members of the flight's crew becoming engrossed in trying to figure out why a single indicator light relating to the plane's landing gear was not working.

As the trio racked racked their brains over the issue, they forgot that the plane's auopilot was on the wrong setting, only realising their mistake too late.

While billions of dollars in technological improvements have reduced the chances of accidents, humans will always be subject to factors that are beyond the scope of improved company policies and procedures.