Flight Envelope Calculation of a Hypersonic Vehicle Using a First Principles-Derived Model

Steady, level flight for an air-breathing hypersonic vehicles requires balancing intricate couplings among the engine, lifting surfaces, and control effectors. A newly developed fundamental model is used to determine the range of flight Mach numbers and altitudes at which this balance can be obtained. The hypersonic vehicle was developed specifically for flight dynamics evaluations, and the model can calculate the net forces and moments on a three-dimensional vehicle in less than ten seconds using a single 2.6 GHz processor. The propulsive model includes complex physics such as wave interactions, fuel mixing, and finite-rate chemistry. This type of model requires less computational resources than a model based on computational fluid dynamics and provides a more accurate characterization of the flight envelope than simplified models could.