Ailerons- A moveable part of the wings on an airplane that control pitching and banking movements.

Airfoil - The shape of a wing, propeller blade, vertical and horizontal fins, etc., whose shape and orientation controls stability, direction, lift, thrust or propulsion.

Anhedral - The downward inclination of an aircraft wing from true horizontal. Most airplanes have "dihedral".

Aspect Ratio - The ratio of the wing chord to the wing span.

Center of gravity - The point at which an item balances.

Dihedral - The upward inclination of an aircraft wing from true horizontal. Dihedral is designed into an airplane's wings to give it more stability.

Flaps - A moveable part of the wing that is dropped into the airstream to increase lift and/or drag.

Leading Edge - The very front, running along the length of the wing, of the airplane's wing.

Lift Coefficient - The measure of lift efficiency for an airfoil. This is usually determined by wind tunnel testing.

Moment Arm - The distance from a point of torque or rotation.

Prototype - The first of it's kind that is built. In our case, it would be the first airplane built from plans.

Rib - Wing ribs are placed along the wing's axis and determine the airfoil of the wing. They also transfer the airplane's load to the wing spar.

Root - The innermost edge of the wing parallel with the fuselage.

Stall Speed - The speed at which an aircraft will stall or stop flying in the landing congifuration.

Tip - The furthest edge of a wing parallel with the fuselage.

Trailing Edge - The rearmost edge of a wing, running along the length of the wing, in front of the any flaps or ailerons.

Turtledeck - The top of the fuselage behind the cockpit area of the airplane. The turtledeck does not normally carry any flight loads of the airplane and is mainly meant to steamline the airplane.

Volume Coefficients - The size of the vertical and horizontal tails in correlation to the wing. These coefficients determine the amount of control and stability the airplane will have.

Washout - Also called "Wing Twist". The term applied to the trailing edge of a wingtip being twisted up more than the shape of the wing at the root. This allows the airplane's wing to stall at the root and the tips to remain in the flying condition as the airplane nears stall speed.

Wing Chord - The dimension of the wing from the leading edge to the trailing edge.

Wing Loading - The ratio of weight of the aircraft to the area of the wing.

Wing Planform - The shape of the wings on an aircraft as viewed from directly above or below the aircraft.

Wing Spar - A rigid or semi-rigid structure that runs through the wing of an aircraft and carries the loads of the airplane.

Wing Twist - See "Washout".