air traffic control: the IBM 9020

What makes air traffic control really fun is filtering out all the noise from inputs and keeping it from cluttering up the operator's screen. Buildings, ground vehicles moving near the airport and migrating birds all generate primary radar returns. It was a little distressing to find out that an ATC saw a newly-installed wind farm as sixty small aircraft all taking off (blades going up) followed a few seconds later by sixty small aircraft all crashing (blades going down).