Altimeter Hud Question

[SkiRich]

Something thats been bugging me for a while are the indicator lights on the altimeter when flying a craft.
I get all the function of the various items.
But the two indicator lights puzzle me.
From a random video i was watching I found out the orange indicator next to the altimeter signifys the fact you are dropping from orbit. Or at least thats what I perceive it to mean.

What does the little blue triangle indicator signify?

[GunsForBucks]

Not sure about the blue triangle but the amber/orange light is collision alert.

You can watch it turn on and off while you fly a plane. Also during a vertical drop the light goes off when you drop your speed low enough to <probably> not crash from landing. The light goes off dropping in on Minimus when your speed is below/around 13m/s

[Rhomphaia]

Triangle is a save state indicator, if blue then you can save, if green you can recover, if orange then you cant save because your engines are firing, and if black you cant save because you are in the atmosphere (or possibly moving across surface on an airless body)

[jclovis3]

Green (more of a cyan if you ask me) means you can go to Green warp stages 5x and greater. No physics is being calculated and everything is settled. Black is in atmosphere when physics for air, surface heat, thrust, vibration and all that is being used, so you can only Quick save (F5) or "Save Game" with physics state, but not exit to space center or main menu, which both create a static save and no physics data.

After 70km of altitude, while on a sub-orbital trajectory, you can cut your engines and have a green arrow to allow switching to space center and leaving game. When you turn on engines (or try to change your heading), it will go orange again and like the black, you can't exit from here without losing your changes since the last static save. While black is more for in atmosphere physics, orange imparts a vacuum physics state without the air friction heating and lift. So green arrow also means you can jump to warp 5x or greater, hence the green arrows used in that kind of warp. Warp 2x to 4x are all orange, just like the indicator in this vacuum physics state.

Interestingly enough, while starting out on the launch pad, you get a green state, but you can also recover.

As for the round light that turns on orange, it indicates you are falling faster than a safe limit for landing, so yeah... it's a crash warning indicator that doesn't care that you are in a stable orbit. As long as you are between Ap and Pe, this will likely be on unless they are close together.

[SkiRich]

Thanks, that was more than I thought it was used for.