After assembling your model, it is important to check that your control surfaces are in good working condition that is, they are going in the right direction. First and foremost, HobbyGulf will help you understand what these control surfaces are, and their function in the aircraft.
What are Flight Control Surfaces?
Aircraft flight control surfaces are the movable surfaces on an airplane’s wings and tail which gives the pilot full adjustable control of the aircraft’s flight orientation by creating a difference in air pressure when adjusted, to produce a force on the plane in the direction you wish. The main control surfaces are the ailerons, elevator, and the rudder.
- Ailerons are located on the outer section of each wing of an aircraft(left and right wing) and are responsible for steering. They deflect in opposite direction meaning that when the aileron on the left wing goes up, the aileron on the right wing will go down at the same time which causes the entire plane to tilt, resulting in a turn or an acrobatic roll in one direction or another.
- Elevators are hinged to the horizontal stabilizer located at the rear end of an aircraft and thus controls the pitch motion by decreasing or increasing the downward force created by the stabilizer. When the elevator goes up, an increased downward force is put on the tail which results in the nose going up. When the elevator goes down, a decreased downward force is put on the tail which results in the nose going down.
- The rudder of an aircraft is hinged to the vertical stabilizer located at the rear end of an aircraft. It allow the pilot to change the horizontal direction in which the nose is pointing by varying the amount of force generated by the tail surface resulting yawing the aircraft. Note that this is not the same thing as turning the plane (ailerons’ job). When the rudder is pushed to the right, it pulls the tail to the left resulting in the plane yawing to the right, and vice versa. Here we see that the aircraft yaws in the same direction as the rudder.
For an animated representation, click the images below
After you have understood these movable surfaces, it’s time to learn how to make sure that these control surfaces are moving in proper direction according to your radio transmitter. This final check is done when standing behind your airplane on the ground.
- For ailerons, when you hold the aileron stick to the left your aircraft’s aileron on the left side should move up and the aileron on the right should move down. When you hold your aileron stick to the right, your aircraft’s aileron on the right side should move up and aileron the left side should move down. Basically, each aileron should move up in the direction you are holding the stick.
- For the elevator, when you hold the elevator stick up, the elevator should go down, and when you hold the elevator stick down, the elevator should go up. It moves in opposite direction as the stick
- As for the rudder, when you hold the rudder stick to the left, the rudder should move to the left and when the rudder stick is held to the right, the rudder should move to the right. It moves in the same direction as the stick.
It is important that during this inspection, when you release the control stick of any of the above, the control surface part related to that stick should return to its original position.
Here is a video with the perfect representation of the information above.