1615. Wing Aspect Ratio Optimization Related to Payload and to Fuel Consumption of Transport Propeller Airplanes

Paper

Abstract

In the preliminary design phase of a new airplane it is very useful to search for the best values of the wing aspect ratio in order to obtain the maximum payload, or the minimum fuel consumption: the wing aspect ratio influences directly the wing weight and obviously, the wing weight decreases, the range and the payload increase, for a fixed total weight.
In the paper, solutions are given relating the range, the payload, and the fuel consumption of a propeller airplane, as a function of the aspect ratio and of the flight attitude in the look of an optimization.
To this aim a very simple but reliable formula for predicting the wing weight is proposed and introduced in the flight performance equations, which are expressed versus the wing aspect ratio only. In this way, many design solutions can be briefly analyzed in a large operational field.
Results allow one to draw diagrams displaying the relation between payload or fuel consumption and flight attitude, for optimum values of aspect ratio at different operational ranges.
These plots are useful in the preliminary design stage in order to define the geometry of the airplane, when operational ranges, load capability economical performance have been already given. They also are of help to customers for choosing the more fit airplane for their requirements.