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In order to comply with the existing standard requirements or specifications, a new computational method for aircraft take-off and landing performance, which deals with the characteristics of the high precision of parameters in the process of take-off and landing based on flight simulation technique. The simulation model for a twin-engine normal layout aircraft is constructed in detail, including nonlinear motion equation, aerodynamic, engine, landing gear and dynamical mass model. According to performance calculation standard and pilot control specification for different take-off modes and landing stages, the simulation process for one engine inoperative(OEI) take-off, angle of attack(AoA) hold take-off, standard take-off, reject take-off and landing are designed, and corresponding performance computer software is developed to achieve the goal of accuracy as well as full parameters calculation. Compared with the existing methods, the computational complexity of this method is increased, the process is detailed, the parameters are increased, and more influencing factors can be analyzed quantitatively. Results show that OEI take-off distance is the longest, standard take-off is suitable for light aircraft, angle of attack hold take-off is appropriate in plateau or limited thrust. Landing distance is related to glide angle. Therefore, light aircraft landing can reduce the approach speed and increase the glide angle.

To solve the taxiing control problem of the full-wing solar-powered unmanned aerial vehicle (UAV) without front wheel steering servo and rudder, a control approach using differential propeller thrust to control the taxiing is proposed in this paper. Firstly, the taxiing mathematical models of two kinds of full-wing solar-powered UAVs with the front wheels turning freely or fixed are established. Meanwhile, the taxiing characteristics of full-wing solar-powered UAV in different taxiing speeds are analyzed. Secondly, based on the linear active disturbance rejection control (LADRC) theory, a yaw angle controller is designed by using differential propeller thrust as the control output. Finally, a straight line trajectory tracking scheme which is suitable for take-off and landing taxiing is designed on the base of improved vector field theory. Simulation results show that the designed controller has a good control effect on full-wing solar-powered UAV's take-off and landing taxiing periods, and better robustness.

A solar-powered unmanned aerial vehicle generally encounters the problems that it has low Reynolds effects and is highly susceptible to gust response. Therefore, the grid velocity method was used to analyze the gust response characteristics of the airfoil FX63-137 under low Reynolds number. First, the reliability of the numerical simulation method at low Reynolds number and grid velocity method were verified with experimental data. Second, the gust response characteristics of FX63-137 airfoil under different Reynolds numbers and different angles of attack were numerically simulated. The results show that the magnitude of incremental lift coefficient in gust response decreases because laminar separation bubbles are complete as the Reynolds number decreases at a small angle of attack. They also show that laminar separation bubbles have an unloaded effect on gust response. At a high angle of attack, as the airfoil enters into stalling stage, the incremental lift coefficient begins to decline before reaching maximum gust disturbance. Because of the stalling of the airfoil, when the gust disappears, the incremental lift coefficient has a negative value. What's more, although the effective angle of attack is equal, the flow structure of the airfoil is somewhat different in upstream and downstream moments. Compared with the downstream moment, the incremental lift coefficient at the upstream moment is generally larger, and the incremental lift coefficient curve of the airfoil forms a non-closed hysteresis loop.

The air flow field of ship was simulated by using computational fluid dynamics technology to analyze its prime characteristics with reasonable accuracy. The different results of Reynolds-Averaged Navier-Stokes (RANS) method and Detached Eddy Simulation (DES) were compared, and the calculation traits of these methods were discussed. The results show that the air flow field of ship is unsteady. The accuracy of RANS simulation is insufficient for capturing this unsteady phenomenon. However, DES can catch this with better accuracy and expresses a comparatively great conformity with experimental data. Then, the aircraft carrier's flow field was calculated by DES. The characteristics of vortexes and velocity fluctuation on the ideal landing track were discussed in different wind directions. Those simulations indicate that there are complicated vortexes produced by blunt edges of the island and deck in the flow field. Those vortexes interact and mainly exist in the rear of flight deck and its adjacent air wake. Moreover, they cause a conspicuous and periodical velocity fluctuation on the ideal landing track as time goes on.