Stability and Control

The methods in these notes allow us to compute the overall aircraft drag. With well-designed airfoils and wings, and a careful job of engine and fuselage integration, L/D's near 20 may be achieved. Yet some aircraft with predicted L/D's of 20 have actual L/D's of 0 as exemplified by any paper airplane contest. Many aircraft have been dismal failures even though their predicted performance is great. In fact, most spectacular failures have to do with stability and control rather than performance.