Program to Calculate the Performance of Airplanes Driven by a Fixed-Pitch Propeller

Accurate numerical methods to obtain the maximum and minimum velocities, the maximum rate of climb, and the absolute and service ceilings are proposed for steady flight of airplanes powered by a piston-engine driving a fixed-pitch propeller taking into account the variations of propeller efficiency and the power available, both by polynomial equations. In addition, a numerical method to compute the take-off performance during ground rolling using a thrust polynomial equation is presented herein. These numerical methods are condensed in a program written in FORTRAN called PienAir (Piston-Engine Airplane Performance). A case study was used to compare the data obtained by this code and the solutions accomplished by traditional methods. The comparison showed that the program calculated the minimum and maximum velocities values with very low rate of error, the maximum rate of climb with a maximum error of 13.41%, and the service ceiling and absolute ceiling with an error of 3.56% and 5.24%, respectively. The code computed the ground roll for take-off by numerical integration, resulting in about a 17.85% error.