Airplane Performance Calculations by Means of Logarithmic Graphs 380146
THE ideas presented in this paper are designed to eliminate all the faults of previous formulas or charts for finding airplane performance, and to provide a method which will be satisfactory for all types of propellers, engines, and airplanes. The same equation for the power required is retained as was used previously, but corrections are applied to it to take care of the increase in power as the burble points are reached.
By a simple device employing two parameters determined by the airplane dimensions, the power-required curve is generalized and then plotted logarithmically. The power-available curve is generalized in a similar manner and likewise plotted logarithmically. Then, by a simple calculation, the method of placing properly these two generalized curves one over the other is found. This procedure results in being able to read directly with no plotting the values from which the performance can be obtained.