Basic Study on Feasibility of Reusable Sub-Orbital Spacecraft with Wings

In this research, the feasibility of a reusable delta winged vehicle that performs sub-orbital flight up to an altitude of 100 km is examined by a three-degree-of-freedom (3-DOF) simulation as an initial study. In the case of a conventional aircraft, the effect of control surface deflection is often ignored in simple 3-DOF simulations because the deflection angle is small, but with a delta wing configuration, the control surfaces must generate higher forces because of the lower distance between the control surface’s center of pressure and the vehicle’s center of gravity. When a control surface is deflected in a 6-DOF simulation, it directly generates a force that affects the vehicle’s path, and the path may differ significantly from the case of a 3-DOF simulation with the control surfaces fixed at zero angle. Therefore, we decided to perform a 3-DOF simulation in which the control surfaces were set to around the trimmed angle. Studies so far have confirmed that the vehicle can fly up to an altitude of 100 km.