Airspeed

[wizzlebippi]

Right now, everything in ksp (AFAIK) is based on ground or surface speed, which is fine for a rocket, and it's all you care about it orbit. The problem aerodynamics is all based off of indicated airspeed and it really hampers realism for aircraft and spaceplanes in atmosphere. So, I propose that ksp use equivalent airspeed in aerodynamics and engine performance. Here's how:

Lets start with assumptions:

1. There is no wind in the Kerbal universe. This makes ground speed = true air speed, or the number they tell you for how fast an aircraft actually goes.

2. Every planet in the Kerbal universe has a standard atmosphere and never changes. This makes calibrated airspeed = equivalent airspeed.

3. Every instrument for measuring airpseed has zero error. This makes indicated airspeed = calibrated airspeed = equivalent airspeed.

4. Sea level density on Kerbin is used as a reference.

Finally, for some math.

equivalent airspeed = ground speed * sqrt(local density/reference density)

For how this will behave, in a vacuum, your airspeed will be zero because there's no air. As you climb, if your surface speed stays constant, your airspeed will decrease. If you take a spaceplane to Eve, your airspeed will be significantly higher than on Kerbin, causing more drag. Likewise, on Duna you will have a low airspeed and less drag.

There's a large number of aerydynamic issues missing from ksp that can be solved with airspeed. If your aircraft stalls at 100m/s, it will always stall at 100m/s. If your aircraft overspeeds and falls apart at 500m/s, it will always fall apart at 500m/s.