The computer model of aerodynamic stand for the training of free flight in the vertical air jet of large diameter is developed. Submerged air jet is created by the rotating aviation screw propeller, which is fixed on the vertical shaft of stationary engine. Propeller with the stator is located in the profiled ring. Method makes it possible to calculate the aerodynamic parameters of jet depending on the velocity of rotation of propeller, to optimize the geometry of propeller, ring and the form of the blades of stator, to analyze the ground effect and limiting walls. Mathematical model is described by nonstationary Navier-Stokes equations and numerically is solved by means of an adaptive movable mesh taking into account and with visualization of the process of rotation the propeller, and also taking in acount the compressibility of medium, flow turbulence, appearance of separation zones and reverse flows. Method is proved by the development of the design of aerodynamic stand “Aerodium”, prepared and installed in the town Sigulda (Latvia) in 2007.