HOUSTON -

Cynthia Hamilton spent her entire career in the sky as a flight attendant for Delta Airlines.

"Something like this happens and you just go into complete shock," Hamilton said.

Hamilton is talking about the horrific plane crash that killed her mother and father in May 1996.

"My girlfriend answered the phone, she said, 'You've got to get in here, your parents were just killed,'" said Hamilton.

Hamilton is now an advocate, pushing for stronger safety measures in the airline industry, and she's very concerned about a new threat that is emerging.

It's a problem the Federal Aviation Administration, National Aeronautics and Space Administration and the National Transportation Safety Board have been quietly warning about for years now, but you've probably never even heard of it.

It's been called "Automation Addiction," the problem of pilots relying too much on computerized autopilot systems and not enough on their own skill. There have been deadly examples of that.

In 2009, Continental Connection Flight 3407 outside of Buffalo, New York, the NTSB determined that the pilots, confused by automation reacted the exact opposite way they should have when the plane went into a dangerous stall, killing all 49 people on board.

Air France, also in 2009, investigators found confusion over automation, and iced-over equipment, played a role in the crash that killed 228 people.

Most recently last summer, in the case of Asiana Flight 214 in San Francisco. Though the NTSB has not issued its final report, NTSB officials have revealed information that the pilots thought the plane's auto throttle was activated, when in fact it had been shut off, and the plane was dropping lower and lower.

"When the autopilot is flying, it's all automated. All you are doing is inputting stuff into a computer," said Clyde Domengeaux.

Clyde flew for Continental Airlines for 35 years. He flies corporate jets now and when asked if he believes commercial airline pilots are relying too much on automation, he says simply, "Yes, I do, I really do."

A new FAA report released in September addresses this very issue and the danger involved. It found in 50 percent of accidents and incidents, pilots were, "Out of the loop...not aware of the state of the airplane."

The report found in 27 percent of accidents, "Pilots were overconfident in automation...and reluctant to assume control from automation." Perhaps most revealing, in 60 percent of all major incidents reported to NASA, there were errors made using the in flight management computer.

The report also found in 35 percent of major incidents, "Automation is too complex because complex systems are often difficult to understand."

NASA is funding a three-year study to examine just how pilots in the cockpit react to all of this automation during long periods of flight.

Thomas "Mach" Schnell, at the University Of Iowa, is leading the project that is studying pilots' eye movements across computer screens, their heart rates, brain waves and reaction times over long, boring stretches of flight.

"Sometimes it's difficult now with highly integrated automated systems for the pilot to recognize it's time to take over from the automation and fly the plane manually," said Schnell.

The goal of his project, which is now in its second year, is to eventually better design automation in the cockpit, to make it easier to understand, easier to read, easier to react to.

After all, as Kevin Gabriel, owner of Solo Flight Training in Houston, a well-respected flight school says, "Automation is just a tool. You have to know when to turn it off when it's not working, and when you need to take over and fly that plane."