Abstract:
Operational analysis programs are a common tool used by operators to simulate the mission outcomes as a means to estimate mission requirements for both rotary wing and fixed wing aircraft. Operational analysis programs are more commonly referred to as "war games". Mission simulations take into account battlefield topography, atmospheric conditions, aircraft capabilities, and potential threats. The outcomes of these simulations aid operators in decisions such as the number of aircraft to be deployed on a particular mission, what type of aircraft to utilize, as well as the overall risk of the mission. Additionally, operational analysis programs have been used to evaluate developmental platforms against each other in a battlefield environment. A key component of the operational analysis program is the flight dynamics models for each of the aircraft involved in the simulation. Aircraft modeling for this type of simulation presents a unique challenge due to the fact that the models must be computationally compact because many aircraft are being simulated. While much research has gone into the creation of high fidelity rotary-wing and fixed-wing models, there are no established standards for computationally compact models to be used in war games simulations. Past attempts to achieve satisfactory model performance used interpolation of aircraft performance data table collected from flight test or a high fidelity simulation. Boeing has implemented a more rigorous method using 6 degree-of-freedom linear aerodynamic models of body-referenced vehicle response. Proportional navigation and control laws are used to drive the models to allow execution of flight plans. The model uses an explicit set of equations for the speed control, turning flight, and climbing/descending flight. The parameters required to populate this model are based on typical control response requirements derivable directly from handling qualities specifications. Different vehicle configurations can be parameterized by using either published data for specific aircraft or by referring to the appropriate handling qualities performance specification which provides guidelines for desired and adequate response. MIL-F-8785C is used to parameterize fixed wing configurations and ADS-33E-PRF is used for rotary wing. In addition to describing our approach to this type of simulation we seek to propose that a uniform set of standards for aircraft modeling be developed for these "war games" simulations.