Ah yes, it is the old mystery of capturing "apparent wind". Apparent wind is the wind that you "make yourself" i.e. you feel on your face as you move forward such as on a bicycle. True wind is the wind that is blowing naturally.
There is a long-forgotten way it could be done today, with huge OU implications, you know: capturing the very wind you make yourself <g> ... for those who do not appreciate a little humor, stop here. http://blog.modernmechanix.com/2007/04/07/propeller-drives-novel-bicycle/ Hey, had this guy not caved into the expert scientists of the day, those that said he could not capture some of his own apparent wind, we might all be riding wind-cycles today :) Maybe the Russians are using the technique on the this helicopter, which seems to be getting a massive amount of lift with almost no blade speed ... cough, cough. http://www.youtube.com/watch?v=qgvuQGY946g Seriously vorticians, if you pedal into the wind on a bicycle, your leg torque overcomes both kinds of wind drag. The proper comparison is between torque and drag. Same with the torque from the wheels of a land sailor. Never mind that some of the torque comes from the wind you "make yourself" even though, above the speed of true wind there is additional drag. At least between 1x and 3x true wind, it appears there is no net drag (vs torque extracted) in a good design. Jones
