The continuing growth in both computing power and commercial space activities has resulted in a number of start-up organizations that are designing new aerospace vehicles using a variety of commercial off-the-shelf and in-house-developed simulation and analysis tools, including six-degree-of-freedom flight simulation tools. Verification of the tools' equations of motion and environment models (atmosphere, gravitation, and geodesy) is necessary to assure credibility of results. However, aside from limited examples in textbooks, very little verification data exists for six-degree-of-freedom flight simulation problems. This paper describes a set of verification check-cases that cover both atmospheric and exo-atmospheric orbital flight. Each scenario consists of well-defined flight vehicles, initial conditions, and maneuvers. These scenarios were implemented and executed in a variety of NASA analytical and real-time simulation tools. The tool set included flat-earth, round-earth, and rotating oblate spheroidal earth geodesy models as well as independently derived equations of motion and propagation techniques. The resulting parameter trajectories were over-plotted to yield a family of solutions. The models are published in the AIAA/ANSI S-119-2011 Flight Dynamics Model Exchange Standard, making them realizable in a variety of proprietary and non-proprietary implementations. This set of models and the resulting NASA-generated trajectory plots may serve as a preliminary verification aide for organizations and individuals that are developing their own simulation tools and frameworks.
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