When you think of a computer, you probably don’t think of a tube full of motors and mechanics. However, as [Our Own Devices] shows, the Bendix AN5841 API Computer, an air position indicator computer, is exactly that. Using mechanical integrators and data from other analog systems on an airplane to provide key flight data to a pilot. You can see the video below.

These devices were made for military aircraft, including the B-29. It is odd that speed data can be derived from a pump that balances pressures using a fan. The video does a good job of explaining exactly how that works.

The way engineers used mechanics to convert physical measurements into analog computations is nothing short of amazing. You have to wonder how you dream up this kind of stuff. Perhaps mechanical engineers wonder the same thing about electronics. But we sort of doubt it.

We are glad our computer doesn’t have any flexible shafts or rotating disks to do math. But we do love looking at ones that did. Some analog computers used voltages instead of mechanics. This video made us think of the M13A1 ballistic computer and, of course, the Norden.