The current radar-based air traffic control system (shown here) will eventually be replaced with a new system called NextGen, which will rely on GPS. A number of computer security experts are concerned that NextGen is insecure and vulnerable to hackers.
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Feb. 16, 2009: Flowers are left in memorial near where Continental Connection Flight 3407 crashed in Clarence, N.Y. Fifty people died. Pilot fatigue was cited as a factor.
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