The rise and fall of IBM's 4 Pi aerospace computers: an illustrated history

The morning of April 12, 1981, 20 years to the day after Yuri Gagarin became the first person in space, the
Space Shuttle thundered into the Florida sky.
Commander Young and Pilot Crippen were at the controls as the Shuttle ascended on its first flight.
But the launch, like much of the flight, was really under the control of four computers in the avionics bays
one deck below the crew. A fifth computer stood ready to take over in case of a catastrophic computer malfunction.
These computers, Model AP-101B,...