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Thrust & Drag Graphs

This graph shows how thrust and drag vary with speed. Generally, thrust decreases with increasing speed. It drops off dramatically above pitch speed . The point at which thrust and drag are equal determines top speed . The steep slope of the left side of the drag curve is below stall speed and is due to the increasing angle of attack. The right half of the curve is due primarily to parasitic drag, which increases as the square of the speed. Occasionally these curves intersect above stall speed. This is a big clue that you might have a candidate for a bungee launch! The two dashed lines are reference curves. They represent props with P=D and P=D/2 with D chosen to draw the same current as your prop. The prop with the highest apparent static thrust has the poorest performance at normal flying speeds. Commit this picture to memory! You can print this graph along with descriptive data by simply clicking the Print button. If you print in Landscape, you will get a larger graph without the data. Return gets you back.

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