A shortage of computer memory in the $2.4 billion Air Traffic Control System caused a Computer crash that resulted in the System collapse, according to an insider close to the incident. The problems began on 30 April, when a U-2 spy plane flew over southwestern US caused the air traffic control system that manages the airspace around Los Angeles’ LAX airport, built by Lockheed Martin, to crash. Now that the “very basic limitation of the system” is known, experts showed concerns about the “cyber-attacks”
Source: https://thehackernews.com/2014/05/air-traffic-control-system-failure.html