Aerodynamic Design and Cross-country Flight Performance Analysis of Diana-2 Sailplane

Abstract

The aerodynamic design philosophy and computational analysis of cross-country flight performance of Diana-2 sailplane in different thermal conditions are presented.  To address the second issue, a continuous spectrum of thermal models is created.  For specified thermal model (thermal strength vs distance from core center, interthermal descent, length and strength of cloud streets), the sailplane mass and aerodynamic characteristics optimum flight parameters (circling speed and bank angle, interthermal glide speed and speed in cloud streets) is found applying optimization technique.  Finally expected cross-country speed for different thermal conditions and water ballast weight, as well the optimum water ballast amount, can be predicted.  The main goal of the analysis is the optimization of sailplane parameters and helping pilots make decisions regarding optimum balasting technique in flight.  An estimation of the influence of bugs and rain on the sailplane aerodynamic characteristics is also presented.