how the Wright brothers invented the airplane

As author Lester Garber has noted, there were a number of key breakthroughs the brothers had to make:
- recognizing that problems of stability and control must be solved before attacking problem of powered flight;
- recognizing that given adequate aircraft, pilot must still learn how to fly;
- recognizing that to maintain equilibrium, control is more important than inherent stability;
- recognizing that use of aerodynamic forces superior to weight-shifting for maintaining control;
- using of wing warping to vary angles of attack from tip to tip for roll control;
- recognizing that aeroplane must bank its wings in order to turn;
- doing wind tunnel tests to determine lift/drag characteristics of different wings;
- realizing that the real value of Smeaton’s coefficient is really .0033;
- recognizing of the need for 3 dimensional control;
- understanding that the proper function of the vertical rear rudder is yaw control, not turning aeroplane;
- the development of a method to design efficient propellers;
- the development of a lightweight engine with sufficient horsepower.
The only real account from the brothers themselves, however, is in an old Harper’s magazine article, which I’ve scanned and posted below (I believe it’s out of copyright):
