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Ken Shirriff

How did fighter planes in the 1950s perform calculations before compact digital computers were available? With the Bendix Central Air Data Computer! This electromechanical analog computer used gears and cams to compute "air data" for fighter planes such as the F-101. 1/13

11 comments
Ken Shirriff

Aircraft get pressure readings from a pitot tube to determine airspeed. But near the speed of sound, the fluid dynamics change and the equations get complicated. To solve these equations, the CADC used the angle of rotating shafts to represent variables. 2/13

erol_foret

@kenshirriff Hello Master Ken. I am following your adventures on Curious Marc's channel. Great job with this incredibly complex mechanical computer! Glad to read you.

soc

@kenshirriff This is probably the best example of analog computing I have seen.
Thanks for that!

The Animal and the Machine

@kenshirriff @ohiorob
Is this basically a Babbage engine in a super super super sonic aircraft?

the roamer

@kenshirriff

Fascinating insights into an analog computing device that works under extreme conditions. Thank you so much for your insightful presentation.

MHowell

@kenshirriff I got to play with a Honeywell ADC chock full of gyros and lasers and mirror, off of a 747-400 being parted out by Stratolaunch. We were going record A429 output data to use in a dumb ADC mimic box, but never got it going. Then someone told me just how expen$$$ive they were, and I put it back into inventory.

Jim Flanagan

@kenshirriff One of these may have fallen out of a plane off the coast of the Greek island Antikythera, landed on a shipwreck, and gotten all rusty.

Giacomo Amoroso

@kenshirriff This is sooo mind boggling, but so ingenious. Thank you for sharing this

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