Fighter planes in the 1950s used the  Bendix Central Air Data Computer to determine air speed, mach number, altitude and so forth from pressure. It is electromechanical, using gears and synchros for its computations. Amazingly, it is modular and can be easily disassembled.

We separated the top layer from the rest for testing. The "interface" between the layers is two gears and an electrical connection. The electronic servo amplifier blocks come off too.

(3 photos in link)