On Sunday, November 10, 2013 10:07:19 AM UTC-5, wrote:
An eternally fantasized about possibility... But now, except for a few famous efforts in very strong wind shear (As I recall, Ingo Renner reportedly did it with a 40 mph wind shear or something like that) can we do this in real gliders?



I tried for a bit in condor, but it doesn't look like its wind shear model is accurate enough. (I was trying to dip in to the lee of a ridge like the RC modelers do, but it looks like condor is set up with the same wind and sink behind the ridge, not the wind shadow or rotor).



These nice videos suggest that somebody somewhere has done the quantitative calculation -- including all losses, how much wind shear (mph/ 1000', or kph / 1000 m) does it take to dynamically soar a modern sailplane? Can we do it with current vnes? The duckhawk is designed with much higher vne and g loadings which make dynamic soaring more efficient. How much shear does it need?



John Cochrane

Gary Osoba, please pick up the white courtesy phone...

Back to Greg Cole's Barnaby lecture, which I highly recommend.

http://www.youtube.com/watch?v=Ln9fuR8uwIc

Dynamic soaring discussion starts 28 minutes in.

Discussion of some flying that Gary Osoba did in the JS-1 starts about 37 minutes in. I would really like to understand more about this particular flight ("dynamic soaring on the edge of a cloud street").

Evan Ludeman / T8