Determination of main performance data of an aircraft threedimensional maneuver split-S with a permissible flight envelope limiter

Abstract

Due to a steady extension of the flight envelope of modern agile combat aircraft, with the growing requirements for state tests, it is increasingly necessary to study the entire flight envelope and specifically, to determine the main performance data of individual maneuvers. Currently, state tests are based on a flight full-scale experiment, which is cost-ineffective in terms of cost, duration, and limit lines of the flight envelope. The accelerating trends to update state tests are semirealistic simulation and complex simulation modeling. The article presents the various techniques to determine main performance data of a three-dimensional maneuver split-S, which include the calculation method, semirealistic simulation, and simulation modeling. The calculation method is understood as calculation formulas expressed from the system of equations for motion of the aircraft mass center. Semirealistic simulation was carried out using a flight-simulation stand by operator pilots. Simulation modeling was conducted using a complex simulation model of an aircraft, consisting of a pilot’s control actions model based on fuzzy logic. The article provides the description, advantages and disadvantages, comparison of the results of each of the techniques. The calculation method, despite its efficiency, is the most inaccurate due to the complexity and inability to define the average flight parameters. Additionally, this method does not take into consideration such factors as the aircraft flight configuration, atmospheric disturbances, the pilot’s command profile, the logic of the permissible flight envelope limiter operation. The results of semirealistic simulation showed that this method is more accurate than the calculation one, but complex and time consuming in terms of the organization and execution of experiments. The analysis of the study illustrated that the most appropriate way to determine main performance data of split-S is simulation modeling on a complex simulation model of the aircraft, because the given method considerably saves financial and time resources used on state flight tests.