Development of a wave drag prediction tool for the conceptual design phase

The goal of this paper is to improve the wave drag estimation techniques in the aircraft conceptual design. Based on the most relevant methods, among those developed in the past sixty years, three methods are proposed as an attempt to include more design variables and improve the accuracy of the wave drag prediction. The proposed methods include the use of supercritical airfoils and the cross sectional area distribution of the aircraft in the wave drag estimation. All methods are compared to experimental drag data available in the open literature of four high-subsonic transport aircraft. An accuracy analysis is performed evaluating how well each method predicts the drag divergence Mach number, the wave drag at Mach number 0.8, and how well the predicted curve fitted with the experimental data. The analysis leads to the conclusion that the Delta method, developed in the 1970s, shows better agreement with the experimental data than any of the proposed methods.