Flight altimeter should have a ground altitude mode

[Renegrade]

No, the laser can only tell you the distance to the object which reflected it back, nothing more. Actually, there's no big difference if its radio or laser - they both are just electromagnetic waves. So, you can use either to determine how far down the surface is (or your target is), but you cannot tell how far the 'baseline' or 'sea level' are or how far is the planet center. What I mean that it's only logical to change the altimeter readout from 'baseline' to 'surface'.

If you have previous data about the shape of the object available to you, and know where you are in terms of it's surface, it's easy to work out what the above 'sea level' or above planetary center altitude is...

(ex, if your radar says you're 5300m above a particular crater of the Mun, and that crater's altitude above the core is 12,950, then you know your orbital altitude above the core is 18,250m)

Anyhow we're getting a bit far afield. The 'above ground level' or 'radar altitude' being requested here is both realistic AND handy-dandy... it's the existing measurement which is questionable If we want to wander off topic, I could always bring up co-incident optical rangefinding and old WW1 and 2 warships and stuff...

[AbacusWizard]

I was so proud when I created from scratch a mathematical formula that, given orbital altitude and mass and thrust of my lander, would predict the precise moment when I should set throttle from zero to full to begin my "suicide burn" and switch from freefall to deceleration.

I was so horrified when I crashed catastrophically anyway.

I was so disappointed when I realized that my math was fine but my inputs were flawed because the altimeter was giving me height above sea level instead of height above ground level.

In other words: YES, PLEASE allow a height-above-ground altimeter mode!

[panzer1b]

Im all for it. Right now its not too bad, but it does cause some issues with low TWR craft that i cant compensate for the altitude via eyeballing as easy.