In this paper, wind tunnel experiments are conducted to study the control law and mechanism of oscillating jet flow control to improve the aerodynamic characteristics of the vertical tail when a civil aircraft encounters left side gust or significant crosswind during takeoff and landing. We measured the vertical tail scaling model’s aerodynamics, spatial flow field, and surface pressure when the Reynolds number was 2.12 × 10⁵. The maximum momentum coefficient of the oscillating jet actuator reaches 0.332%. In addition, we studied the flow control effect of the three-dimensional vertical tail scaled model in different spanwise positions. The experimental results show that the oscillating jet at the rear edge of the stabilizer can significantly increase the lateral force of the vertical tail, and the increment of the lateral force can reach 36.5% under the worst condition of the negative side slip angle of the vertical tail. We can improve the lateral force coefficient of the vertical tail model by applying flow control alone at different spanwise locations. The wing root’s control effect and the vertical tail’s middle section are better than the wing tip’s. The oscillating jet can effectively restrain the flow separation on the rudder. In addition, the input of a high-energy jet “ejects” the mainstream, which increases the flow velocity at the side of the vertical tail actuator. It increases the circulation of the vertical tail. The oscillating jet flow control technology can effectively improve the vertical tail’s steering efficiency and increase the vertical tail’s lateral force, which is of great significance in improving the safety and economy of civil aircraft.

Plasma synthetic jet (PSJ) is widely employed in flow control due to its advantages of zero-mass and fast-response. A novel measurement method for high-frequency dynamic drag variation was adopted in a Mach 8 wind tunnel experiment, demonstrating that the opposing PSJ can achieve a maximum drag reduction of 40.27% and an average drag reduction of 13.25% within one discharge cycle. Subsequently, the numerical method was verified in detail and the effects of different discharge energies and nozzle diameters on the drag reduction characteristics of the opposing PSJ were studied. The results show that an increase in discharge energy is beneficial for the drag reduction characteristics of the opposing PSJ, although the efficiency remains relatively low. In contrast, increasing the nozzle diameter enhances the average drag reduction but significantly reduces the duration of effective control. The drag reduction mechanism of the opposing PSJ can be attributed to the combined effects of pushing the strong bow shock away to form a weaker oblique shock, followed by the reattachment of the shock downstream.

To address the complex aerodynamic disturbances encountered by the first stage of reusable launch vehicles (RLVs) during Supersonic Retropropulsion (SRP) in the re-entry phase, this study conducts a systematical wind tunnel investigation of a typical slender cylindrical rocket model equipped with thrust vector control (TVC). Aerodynamic forces, surface pressures, and spatial flow field characteristics were measured across varying thrust vector angles (0°, 5°, and 10°) and angles of attack (0°, 5°, and 10°). Experimental results demonstrate that the activation of retropropulsion induces a typical short penetration mode (SPM), which significantly reduces the axial force on the vehicle and alters the surface pressure distribution. The introduction of thrust vectoring disrupts the global symmetry of the flow field, leading to a highly non-linear variation in the pitching moment. A small thrust vector deflection (δ=5°) shifts the center of pressure forward, weakening the restoring pitching moment and potentially inducing local instability. Conversely, a large deflection (δ=10°) shifts the center of pressure rearward, partially restoring static stability, but induces severe interactions between the bow shock and the oblique shock on the windward side. Furthermore, Proper orthogonal decomposition (POD) analysis of high-speed schlieren images reveals that as the angle of attack increases, the dominant flow mechanisms transition from high-frequency, globally coherent shock oscillations (with a characteristic frequency of approximately 4263.1 Hz for the first mode 1) to low-frequency, highly chaotic unsteady structures, significantly increasing flow complexity. These findings quantitatively elucidate the non-linear coupling among thrust vectoring, angle of attack, and aerodynamic loads, providing crucial experimental data and theoretical guidance for aerodynamic shape optimization and control law design during the powered descent and landing phase of reusable rockets.