The point is that it's distinguished by a lot more than just color. Shape, positioning, texture, etc are all used to seperate functionality (which is a hard-earned lesson in aircraft: there have been plenty of accidents because a pilot confused two similar levers/buttons/etc - one famous example was the lever to raise the landing gear being next to the throttle, which resulted in more than one case of it accidentally being raised while landing)

> There always is a switch that cuts enginees off and from what my pilot friend tells me using it in mid flight is more or less equal to killing everyone.

Now I'm curious about that! Is that for a situation in which there is absolutely no hope, but bringing the plane down *now* would be better than not doing so? I.e. it's a kind-of aerial trolley problem?

Yeah, we learned a lot about user interface design during WWII from things like this.

The B-17 was one of the first 4-engine planes and some people thought it was impossible to fly, but really there were issues because the "raise/lower landing gear" and the "dump fuel overboard" switches were basically next to each other and used identical toggles to save money.

Now the landing gear switch is a big handle with a wheel on the end aka it looks like a landing gear and the fuel dump switch is under a protective Molly cover and they are far apart.