a http://www.pagendarm.de/trapp/programming/java/profiles/NACA4.html Angle of attack Middle line Velocity Cord http://www.pagendarm.de/trapp/programming/java/profiles/NACA4.html

c Lift FL Drag FD

Pressure distribution around an airfoil - Pressure along the upper surface DH + Pressure along the lower surface http://www.desktopaero.com/appliedaero/

Lift Lift FL

Lift coefficient CL FL

Drag Drag FD

Drag coefficient CD FD

Blade profile data Angle of attack d v Angle of attack Average relative velocity

Peripheral velocity = w Wind velocity = C Relative velocity = V V C U

U V Torque Trust C FL FD

U V C Torque Trust U V Torque C Trust

C Fthrust Torque Trust M’torque w F’thrust M’thrust