As an intern 25+ years ago I had an assignment to draw up mocks for a new UH-1N interface based on pilot feedback. There were a lot of rules (I think all under

As an intern 25+ years ago I had an assignment to draw up mocks for a new UH-1N interface based on pilot feedback. There were a lot of rules (I think all under the umbrella of "MIL-SPEC"), but I think the one that sunk in the most was that the design had to work in monochrome. Depending on shades and colors breaks the design for the color-blind but also ruins interactions in bad lighting conditions, wearing helmets, etc. It was a bigger, bolder look than was common on desktop computers, and I've always personally loved the style. There was a brief rise of similar rules in the civilian world as things moved mobile and we had to work on small screens with big fingers, but the direction now is to try to remove anything that might hint of interaction from the screen entirely. (Not a fan of this myself!) I've been in civilian work pretty much ever since so I have no idea how things have changed since then. Edit: on second glance I think a lot of the same principles are still in effect. While colorful I'm not sure that anything depends on reading the color, and seen from the pilot's chair it probably isn't all that crowded.