Germanwings Crash: How Often Pilots Commit 'Aircraft-Assisted Suicide'

Researchers examined 20 years of plane crash data to delve into suicides.

Of the 7,244 fatal airplane crashes in the United States from 1993 through 2012, 24 were the result of aircraft-assisted suicide, the authors concluded in the 2014 study published in the journal "Aviation, Space and Environmental Medicine."

That's 0.33 percent, and they noted that most of these flights were private, not commercial.

"Somebody knew," Vuorio said. "They’re [crash investigators] not saying the aviation doctor knew. That information was there, but it wasn't spoken about and that's sad.”

The Federal Aviation Administration requires pilots to undergo medical evaluations at least once a year, but Seattle-based aviation analyst Todd Curtis, said psychological conditions are mostly self-reported.

"If you self-identify that you have certain things wrong with you, you can be denied license," he said. "If you can pass a medical exam where there's very little vetting of information outside the exam, sure, you can fly."

The FAA was not immediately available for comment.

In Europe, pilots "may" be required to undergo psych evaluations and those with "schizotypal or delusional" disorders will not be allowed to fly, according to published guidelines.

Japan Air Lines in 1982

In 1982, a Japan Air Lines pilot reportedly "lost his senses" and crashed a plane carrying 150 people into Tokyo Bay, killing 24 of them but not the pilot, according to the New York Times. There was reportedly a fight in the cockpit before the plane went down.

Silk Air in 1997

"The accident can be explained by intentional pilot action," they said in a letter to Indonesian investigators in 2000. "The evidence suggests that the cockpit voice recorder was intentionally disconnected."

Egypt Air Flight 990 went down near Nantucket, Massachusetts, in 1999, killing all 217 people on board, ABC News reported at the time. Investigators concluded that there was nothing wrong with the plane itself -- as EgyptAir suggested -- and wondered whether the crash was intentional.

LAM Mozambique Airlines in 2013

The accident remains under investigation.

Malasia Air in 2014

Despite more than a year of searching, the plane has not been found.

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