bagmaker wrote:
Thanks to all for the information on winglets and lift production in
general.
It seems there is still a lot to be learned in design of airfoils, even
NASA cant give a defintive, simple explanation of what produces lift, in
what amount the sucking or deflecting proportions are.
The hours of research available from some of your suggested links has
left me with bleeding eyes and a sore back, for those who want the
simple version, my reading of it is-

Wings produce lift by diverting air down. The reactive force is up, the
balance is drag.
Winglets enhance the lift produced from the wing by minimising vortices
(drag) produced where the upper and lower airflow mixes at the wing end.
The balance again is drag, it wouldnt matter if they were up or down
facing, for the purpose of aerodynamics.

I particularly liked the spoon-in-waterflow demonstration (so did my
kids) and recommend everyone tries it.

Boom time here in oz, 1000k flights, competitions, sun, sun, sun.

Wayne


--
bagmaker

Probably one of the best lectures I've ever heard on any subject, was
given by Mark Maughmer of PSU on the subject of winglets. I highly
recommend it if you ever get the opportunity.

Chip F