Doug, A 'zero degree angle of attack' is established by each airfoil's lift, drag and moment data. Some airfoils generate lift at zero degrees. usually those with camber. also some wings have more than one airfoil. The whole airplane surface generates lift and drag which also varies with AOA and yaw ... And also varies but little when we use the tail to balance for different CGs... And a little for deployed flaps and gear. Usually not much. And does not vary with weight, airspeed, Gs, etc. I mark my AOA vane at it's stall angle,and when makings turns onto final avoid coming within five degrees. A best-L/D mark is useful for climb regardless of weight, etc. FWIW.
Terrence N211AL 235/320 Waco AristoCraft O'Neill W O'Neill Magnum & V8 Pickup Mitchell Wing/O'2 EZ Riser Dragonfly
Qual in Porterfield, Cub, Ercoupe, Aeronca, SM Cessnas SNJ 3,4,5,6c, SNB, P2V5&5F,
Sent from my iPad
Question for all the aerodynamicists out there.
If a plane is flying, its wing must be generating lift. Does a wing generate lift at a zero degree angle of attack?
I thought that there must be some positive angle of attack in level flight. Am I wrong about this?
And if I am right, shouldn't the angle of attack be set to some small positive number?
-----Original Message-----
From: Sky2high@aol.com
Sent: Feb 7, 2014 9:46 AM
To: lml@lancaironline.net
Subject: [LML] Re: Angle of attack
Tom,
Interesting. The wing has wash out so different parts of the wing are
at slightly different AOAs (think propagation of stall). The design has
the longeron at zero degrees at cruise, flaps at reflex (think chord line from
leading edge to flap TE). Even average angle of incidence doesn't work
because of wing/flap design. Why not use zero, 1 or 2?
Scott krueger
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