The Wright Brothers

In aeronautics, camber concerns the curvature of an airplane wing—specifically, the difference, or asymmetry, between the curvatures of the top and bottom of a wing. Camber determines the amount of lift that a wing produces, which is important for controlling a plane and keeping it airborne.

Drag, or air resistance, is the force on a plane as it moves through the air. Friction and other phenomena create drag, which exerts pressure and slows the plane. A more aerodynamic shape creates less drag.

When all the forces on a plane, such as lift and drag, are in balance, the plane is in equilibrium. This ideal condition allows the plane to stay in the air.

The Wright brothers named their planes Flyers. McCullough uses the distinction Flyer I, Flyer II, and Flyer III to refer to specific versions in which the brothers made improvements. Flyer I was the original model with an engine, while Flyer II was larger and had a more powerful engine. In Flyer III, which had a still more powerful engine, the brothers positioned the forward rudder farther forward than in the others, which gave it better longitudinal control. Of course, the brothers made many other modifications to each version during their testing.

Lift is the aspect of force air exerts on a plane’s wing that pushes up and allows the plane to take off and stay in the air. This force arises from the differential in air pressure above and below the wing based on its camber (or curvature). Air moves faster over the more curved top surface of a wing and slower over the less curved bottom surface. The result is greater pressure on the underside of the wing, which creates lift and allows the plane to become and stay airborne.

Pitch is the movement around the lateral axis of a plane, which is the center of gravity and which a line from one wingtip to the other represents. A plane’s pitch causes its nose to rise or fall, influencing the aircraft’s direction in the air relative to the ground.

The counterpart to pitch, roll is the movement around the longitudinal axis (front to back) of a plane. Roll refers to one wing moving higher while the other moves lower, like the rocking of a ship.

The Wright brothers used a system they called wing warping to control the lateral movement of their Flyers and allow the pilot to change direction. They based this system on how they observed birds using their wings, raising the tip of one while lowering the tip of the other. The brothers controlled this by attaching lines to the tip of both wings that the pilot could adjust during flight.