Investigation on SpaceLiner Booster Configuration with Variable Wings

Abstract

A preliminary study investigating the possible variable wing options for the booster of the SpaceLiner is conducted. This investigation is mainly motivated by possible shock-shock interaction in the area of the wing leading edge during the first part of the booster descent. Based on the previous SpaceLiner 7-3 booster configuration modifications of the wing geometry are performed. Three wing types are studied: fixed wing, variable sweep wing and foldable wing. As a first step the general architecture for each of the wing types considered is laid out. Mass, centre of gravity and aerodynamic data sets are evaluated with the main purpose of maximizing the aerodynamic performance and keeping the mass as low as possible. Particular attention is paid to the subsonic part of the descent, during which the booster is supposed to be in-air captured by a towing aircraft. Some simplified and preliminary calculations are done to estimate the flight performance during this part of the mission. Moreover, an analysis on the existence of a trimmed condition for the entire Mach range is carried out. The most promising configuration among those studied is selected for further investigations. The second part of the study includes the simulation of the ascent and the descent trajectory of the selected configuration. The TSTO orbit mission is taken as a reference for this study. Once the descent trajectory is computed, the Thermal Protection System can be designed. Two different sets of materials are considered for the TPS: one is composed of non-metallic materials only, while the other is made of both metallic and non-metallic materials. The analysis is performed using tools developed at DLR. For the subsonic and supersonic regime the tool CAC is used, while for the hypersonic regime the tool HOTSOSE is employed. Aerodynamic coefficients of the selected booster configuration are also analysed with Missile Datcom.