First, let's take a look at what is three channels?
The channel is actually the control function of the remote control on the airplane. The three channels mean that the remote control can control the three functions of the airplane! One channel is to control the rise and fall, the other channel is forward and backward, and the other channel is to turn left and turn right! There are three channels! Now some planes are marked as 3.5 channels, and another channel is actually the gyroscope circuit installed on the aircraft.
Let me talk about the dual-propeller structure of the remote control plane.
The two-tier propeller has a greater lift and is more suitable for aircraft with low motor speed. The motor speed is lower at a low cost, so the current small aircraft uses this structure.
In addition, the double-layer propeller has another very important function, that is, steering !!
First, I would like to introduce the principles of the flight before and after the plane. As we all know, when a helicopter is flying, its blades rotate and the rotating blades form a circular plane, when the plane is tilted forward, a backward thrust is generated, causing the plane to fly forward. Similarly, when it is tilted backward, the plane will fly backward. But how is this plane Tilted? This is the role of the steering gear. The aircraft manufacturer installs a mechanism on the root of the blades to enable the blades to move up and down. This mechanism is promoted by the steering gear. When the blades rotate, the steering gear pushes the blades to make the circular plane formed by the blades Tilt forward or backward, so that the aircraft can fly before and after.
Because the popular shared-shaft dual-propeller helicopters are cheaper, they do not use complicated steering gear drive structures to reduce costs. However, without the steering gear, it is difficult to implement the flight before and after the plane. In order to realize the flight before and after the plane, a clever engineer adds a horizontal blade to the tail of the plane. When the slurry leaves rotate in the reverse direction, the tail of the plane will jump up or down. When the tail of the plane is tilted up, the circular plane formed by the propeller will tilt forward, then the plane will fly forward, which is the same as the steering gear. With this structure, the aircraft can fly forward without steering gear !!
However, there is also a problem. That is, the tail of the helicopter was originally equipped with a vertical small leaf, which is used to push the aircraft to the left and right directions. The tail of the aircraft is pushed to the steering position when the blade rotates in the forward or backward direction to achieve the purpose of aircraft steering. However, now the tail motor of an airplane is used to achieve the goal of frontend and backend flight. How can the left and right steering functions of an airplane be realized?
We can see from our close observation that the two blades of the co-axis dual-propeller helicopter are in the opposite direction! When the rotation speed of a layer of blades slows down, the plane will rotate in the opposite direction. This type of aircraft relies on the remote control to control the rotation speed of a certain layer of the aircraft to achieve the purpose of aircraft steering.
From the introduction, we can see that the three-channel remote control helicopter's front and back flight relies on the tail motor tail propeller to bring the tail up or down. The left-right steering of an airplane depends on the speed difference between the double-layer blades. Of course, the rise and fall of an airplane is achieved by the joint changes of the speed of the double blades.
