Kerrison Predictor
More info
- Creator
- A. V. Kerrison, Admiralty Research Laboratory
- Released
- 1939
- Type
- Analog fire-control computer
A 1939 British anti-aircraft computer where the operator's only job was to keep the sight on the aircraft; the machine did everything else, including aiming the gun.
Earlier anti-aircraft directors required a crew to read off altitude, course and speed, consult tables and wind the answer in — time an attacking aircraft does not grant. Kerrison inverted the arrangement. Two operators did nothing but hold crosshairs on the target; the machine derived speed and course from how the sight moved, computed the lead, and drove the Bofors 40 mm mount's laying motors directly through servos. Nobody in the chain performed a calculation.
It was expensive and slow to build — Britain ended up having it made under licence in the US as the M5 — but the principle outlived the hardware. Closing the feedback loop all the way from observation to gun, with servos correcting themselves, is the same problem Norbert Wiener was working on for American anti-aircraft fire a few years later, and one of the threads that led him to the word cybernetics.