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High speeds and maneuvering ability both call for small wing areas and short spans, the areas being so adjusted that the resistance is at a minimum at the highest speeds. The short spans have a minimum of exposed interplane bracing and thus indirectly reduce both the head resistance and the weight. Unfortunately, the most favorable areas at high speeds are too small for safe landing speeds. With a fixed area, the minimum landing speed is only a little less than one-half of the maximum flying speed, hence with a maximum of 150 miles per hour the minimum will probably be little less than 70 miles per hour. The most efficient wing sections, and the greatest refinement in the body design, bracing, and chassis are necessary at speeds of over 100 miles per hour. All other conditions being equal, the resistance varies as the square of the velocity, hence at 150 miles per hour, the resistance is 2.25 times that at 100 miles per hour.

The following table gives approximately the apportionment of the head resistance producing items in a typical speed scout or chaser.