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Use of low fidelity tools in designing subscale generic wind tunnel models is usually required to get first-hand knowledge about general trends of aerodynamic and stability parameters. Most of such tools are limited to well-defined conventional aircraft configurations. In the present work, aerodynamic and stability characteristics of a winged hybrid airship is explored at low subsonic speed by using Aircraft Digital DATCOM, which is based on semi-empirical methods for preliminary aircraft geometries. Spheroidal ellipsoidal shaped hull of the airship is modeled in DATCOM along with the geometrical details of wing and empennages. The prediction of zero lift drag coefficient, coefficient of lift and pitching moment is the focus of this paper. Except the drag coefficients, trends of analytical results compare well with experimental data.

Aerodynamic analysis and calculation are very important parts in the aircraft design, and aerodynamic engineering prediction is widely used in the aircraft preliminary design stage. However, traditional aerodynamic engineering prediction causes heavy computation and is time-consuming. The developed software such as DATCOM has the disadvantages of complicated operation and black box structure. To overcome the disadvantages above, we develop the software for aerodynamic engineering prediction based on the aerodynamic characteristics and prediction for aircrafts. There are three parts in this software which are database, calculation module and user interface. The software is verified by a numerical example of one aircraft, and compares with the data of Computational Fluid Dynamics (CFD) and the wind tunnel test. The results show that the calculated results of the aerodynamic engineering prediction and CFD are basically consistent, and the software is able to meet the accuracy demand in the preliminary design phase of the aircraft.

In this paper, preliminary effort of pre-flight test lateral control method study is presented. Parameters and coefficients of candidate UAV (Unmanned Aviation Vehicle) are calculated for modeling and linearization. For controller design, dynamic inversion is used to cancel the dynamic coupling between attitudes. Stability of inversion loop controller which applied on non-ideal inversion is studied. Finally, simulation is present to compare the PI and nonlinear PI controller based on dynamic inversion.

This work aims to simulate and study the flow field around SAFAT-01 aircraft using numerical solution based on solving Reynolds Averaged Navier-Stokes equations coupled with K-ω SST turbulent model. The aerodynamics behavior of SAFAT-01 aircraft developed at SAFAT aviation complex were calculated at different angles of attack and side slip angles. The x,y and z forces and moments were calculated at flight speed 50m/s and at sea level condition. Lift and drag curves for different angles of attack were plotted. The maximum lift coefficient for SAFAT-01 was 1.67 which occurred at angle of attack 16° and Maximum lift to drag ratio (L/D) was 14 which occurred at α=3°, and the zero lift drag coefficient was 0.0342. Also the yawing moment coefficient was plotted for different side slip angles as well as rolling moment. The longitudinal stability derivatives with respect to angle of attack, speed variation (u), rate of pitch (q) and time rate of change of angle of attack were calculated using obtained CFD results. Concerning lateral stability only side slips derivatives were calculated. To validate this numerical simulation USAF Digital DATCOM is used to analyze this aircraft; a comparison between predicted results for this aircraft and Digital DATCOM indicated that this numerical simulation has high ability for predicting the aerodynamics characteristics.

The flight Performance of missile can be improved by adaptive morphing wing serving as main lift surface. A novel compounded morphing missile, a complicated nonlinear and non-analytical multivariable constrained optimization problem, is modeled to design adaptive program of the wing geometry versus flight states. Based on reformed optimal algorithms such as Monte Carlo and Particle Swarm Optimization (PSO), a set of integrated approach is developed to optimize the shape change program of wings by interactively reading and writing data files from missile DATCOM. The simulation results show that the proposed algorithms can be used to obtain an optimal missile configuration over large flight envelope, characterized by maximal lift-to-drag ratio and a required normal overload.