David M. wrote: > I'm getting seriously out of my depth here, since I didn't even take high > school physics, but as far as I understand the most important part of lift > is the suction created by the partial vacuum *above* the wings -- that means > that wings are pulling air down more than pushing it down, effectively, and > the hstab will be in downwash even if it is level with or slightly above the > wings. Only a very high hstab, like the one on a t-tail, will be clear of it. > > Now Jon, Tony, or Andy can step in and explain how I've totally > misunderstood the aerodynamics.
I've heard it described several ways (lift); I think you're pretty close. I don't know if I'd say "partial vacuum", though, which might give an exaggerated impression. Thinking of Bernoulli's nozzle example from elementary physics, the flow over the top, curved surface of a wing sees faster airflow, and lower pressure. Integrating the pressure over the lower and upper surfaces of the wing results in a net upward force (assuming steady-state flight). Probably there is a bit of both pushing _and_ pulling going on. If the lower surface of the wing is at a positive alpha, it's not too difficult to think that there is some "pushing" going on. Well, it would be interesting to get Tony's impression, and of course a physicist will describe this in his own way, too. Jon _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d