According to the BBC a spy plane "was responsible for a computer glitch that caused air-traffic chaos in western US states last week, the Federal Aviation Administration (FAA) has revealed."
The problems started when the system was overloaded, as it struggled to plot new courses for all affected aircraft to avoid the spy plane. Apparently the FAA has now added more flight-processing memory to the computer system.
The Reuters report can be read here - Air traffic computer memory shortage behind air chaos
Alwyn Scott and Joseph Menn write:
FAA spokeswoman Laura Brown said the computer had to examine a large number of air routes to "de-conflict the aircraft with lower-altitude flights". She said that process "used a large amount of available memory and interrupted the computer's other flight-processing functions".
The FAA later set the system to require altitudes for every flight plan and added memory to the system, which should prevent such problems in the future, Brown said.
Come to think of it, it's always a "glitch" with computers, isn't it? But where does the term come from.
According to Wikipedia...
The term derives from the German glitschig, meaning 'slippery', possibly entering English through the Yiddish term glitsh.
Moving on from the familiar glitch, there also a runt pulse, which is new to me ("a pulse whose amplitude is smaller than the minimum level specified for correct operation"). Anyway, that's a whole 'nother story...