For as long as I can remember I dreamed of the highest detail, most interactive mechanics and cockpits some day being possible to create with this game. This is actually partly why I started work on my Wildcat. However, I have realized that further development of cockpit mechanics, which includes a variety of functioning gauges, is simply beyond the current mechanical limits of SimplePlanes. Raw inputs would solve many of the following issues, but first let's dig in to some examples I have thought of and tested with;

Most of my thinking has went to making a proper altimeter mechanism and although I have gained considerable progress with a propeller on a vertical rack that moves a gear, it is still nowhere near the accuracy nor stability of a real altimeter. The idea was that the propeller would lift the pinion, and when the propeller lost power at higher altitudes, the pinion would lower thus moving the gear clockwise, which also contained a needle giving an idea of altitude.
The problem I found was that although it gave an idea of altitude, the loss of power with the propeller was nonlinear over altitude, and so the movement was inaccurate to the actual altitude. Also, with the way the system was put together that allowed it to function, it suffered excessive shaking when the aircraft was moved by either pitch or roll.

I have also thought about ways to make other gauges such as speedometers, vertical speed indicators, among others. Speedos and VSIs could likely be done with drag-based designs, however they would likely affect the performance of the aircraft itself. Also, this method would also suffer the same inertial shaking issues as the altimeter idea I tested.

Motor-based speedometers using the Velocity input would be extremely unsmooth, and would require tens, possibly even hundreds of motors to work as smoothly as a real speedometer. And, piston-based versions with the Velocity input would also require an extreme amount of pistons in a small space in an even more complex pattern to make it work smoothly and accurately.

These issues with what is currently possible is why I put forward the idea of implementation of raw data inputs that can be used by any part that uses an input controller. With this, speedometers can be made with motors inputted to airspeed, altimeters with motors to altitude, VSIs to climb rate, compasses to direction of the aircraft, and/or even clocks to the time of the day while in-game. With the inputs updating very quickly, these gauges would work flawlessly and accurately, and can be changed to different units by changing the min/max values (for example: making a speedo in knots instead of mph or an altimeter in miles instead of ft).

The addition of these inputs would help people build cockpits that better interact with the player, perhaps so much so to make it possible to rely only on the cockpit itself. I hope that soon these will be added into the game. Thank you.