> How would I go about calculating an accurate CD on my rocket for use in
> wRASP? The default is .600 I think.
>
> J.A. Michel
I usually fly the rocket with a recording accelerometer/altimeter, and work backwards from the velocity trace, deriving the Cd from the velocity and deceleration in the coasting phase (preferably in the hugh subsonic region, so there's plenty of drag but no weird shockwave effects).
0.6 actually seemed to be about right for the rocket I did this with (6" diameter, 'bout 9 or 10 feet long depending on configuration, 4:1 ogive nosecone).-dave w