Vertical take-off and landing-the top ten key future equipment of the U.S. military
Because it is not restricted by take-off and landing sites and can adapt to complex terrain environments such as navigation and mountains, the United States has listed vertical take-off and landing aircraft as the top ten U.S. military
Coming to the top of key equipment. There are two main technical routes for vertical take-off and landing fixed-wing UAVs. 1) Tilt-rotor UAV: ​​launch by rotating
The motivation direction provides the lift and thrust required for the two phases of vertical take-off and landing and forward flight. The representative model is the American V-22 Osprey.

The drone version “Eagle Eye” and my country’s Rainbow-10, etc. 2) Rotor fixed wing compound type: adopts two sets of power systems, the rotor provides vertical
Lift, powered by the propulsion engine in the fixed-wing mode, representative models include Zongheng shares “CW Dapeng” series, Rainbow CH804D and so on.
The electric propulsion system can replace complex mechanical transmission components and optimize the configuration of the tilting rotor. The tilt-rotor configuration can ensure good vertical take-off and landing
Under the premise of performance, the efficiency of level flight is improved, thus taking into account the vertical take-off and landing capability and cruising economy. Compared with the rotor configuration, it can be greatly improved
voyage. The research and development and application of tilting rotor technology have been in use for decades, and models such as V-22 have been obtained in special operations and other scenarios.

Widely used, but using traditional power system tilt rotor aircraft, its engine power output mechanism and rotor need to be extremely complicated
The mechanical transmission components significantly increase the complexity and weight of the platform, and have a certain impact on reliability. The application of electric propulsion system is effective
Avoiding the above risks, the motor can be directly placed at the tilting wing assembly, and the motor can be driven by the transmission of electrical energy through the cable, without the need for a power transmission unit
Parts, greatly reduce the complexity of the mechanical structure, and its maintenance characteristics can be guaranteed.
Compared with the tilting rotor configuration, the mixed configuration of the fixed rotor wing simplifies the structure and avoids the influence of the tilting components. Rotor fixed wing compound
The UAV is equipped with a fixed-pitch propeller at the front and rear of the middle of the wings on both sides to provide the lift required for vertical take-off and landing.
A propulsion propeller provides thrust during the cruise phase of level flight. In the horizontal cruise phase, the 4 propellers at the wing position will be stopped and fixed
In the position of least resistance, thereby reducing the resistance during level flight. The hybrid configuration takes into account the vertical take-off and landing performance of the multi-rotor aircraft and the solid
Compared with the tilt-rotor configuration, the fixed-wing aircraft has the characteristics of high-efficiency level flight. The hybrid configuration has a simple structure and no tilting parts. Secondly, fix
The coexistence of the wing and the rotor structure is actually a kind of compromise. The two will affect each other. On the one hand, the structure is large in mass, and on the other hand, the efficiency is limited.
During the vertical take-off and landing phase, a large area of ​​the wing will increase the take-off and landing resistance; in the level flight phase, the rotor will increase the resistance. In order to balance this influence,
The propeller can be stopped and the position can be fixed during the level flight phase.