Gents:

 

I noticed that Columbia Aircraft has formed a “300 Knot Club” for those flying the Columbia 400 at 25k feet lucky enough to find a 70 knot tail wind and take a photo of the ground speed on their GPS.

 

Based on your experience, (marketing literature aside) what kind of true airspeed could a guy expect in a IVP with a Continental TSIO550 at 25k feet?

 

Thanks in advance,

 

John Hafen