The U.S. Centennial of Flight Commission (2003) presented its Responsibilities as follows:
- The United States Congress charges the Commission with playing the leading role in coordinating and publicizing activities celebrating the achievements of Wilbur and Orville Wright and commemorating a century of powered flight.
- Use our Web site to access the most up-to-date information on celebration activity as well as the most comprehensive collection of outstanding educational essays, multimedia and links regarding the history of flight.
Theories of Flight and Airfoils and Wings presented as state-of-the-art 2003 the Kutta-Zhukovsky circulation theory from 1903:
- The airflow about an airfoil may be viewed as consisting of two superimposed patterns—one is the free-stream motion of the air about the airfoil and the other is a circulatory flow, or circulation, around the airfoil.
- These two flows coexist to give the total flow pattern.
- The question is, if the free-stream flow is prescribed or set, can the circulation, represented by G be of any value?
- A physical condition provides the answer. The flow about the pointed trailing edge cannot turn a sharp corner without the velocity becoming infinite.
- As this is not possible in real airflow conditions, the flow instead leaves the trailing edge tangentially and smoothly.
- This is the Kutta condition and it sets the required value of G so that the rear stagnation point moves to the trailing edge.
The Theory of Flight has thus not changed over a century, while the Practice of Flight has evolved through several generations of revolution. This is only possible with a theory well separated from reality, as shown on The Secret of Flight.
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