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If you have just joined us at this blog site, you will want to be sure to start reading with the first post.  The order of posts in the blog is the most recent is at the top — scroll down to see previous posts. This series of daily posts is about how to get started in radio controlled model airplanes.  You won’t want to miss any of the preliminary information.

The following photos will help explain how the R/C model airplane is controlled remotely with the radio equipment.  The first picture shows the model and the 6 channel radio transmitter that is used to fly this model.  This is not a trainer and really not the best suited to learn how to fly with.  Notice that this is a low wing pattern plane.  It is best suited to high speed and intricate aerobatics.  The controls work the same for a high wing trainer, but we didn’t have one available at the time for demonstrating how the plane is controlled.  This R/C airplane has a .46 OS engine installed and it has been flown many times without accident.

The next picture shows the inside of the model plane’s fuselage with three servos installed.  On the right, crosswise to the length of the fuselage is the throttle servo.  Note the control arm and the connection to the push rod.  Typically, most servos move a total range of 90 degrees, however, with the computerized radio system, you can limit the range of the servo’s movement to match the full range needed for the engine’s throttle mechanism.  By doing this you will prevent overloading of the servo motor.  The other servos in this model are used to control the elevator, rudder and ailerons.  The elevator controls how the R/C model airplane climbs or descends when in flight.  The rudder is used to control the model when maneuvering on the ground and in conjunction with the ailerons to steer the aircraft in flight.

Below, are two photos showing the rudder in both the left and right position.  Moving the rudder towards the right causes the model to turn to the right and moving the rudder to the left turns it to the left.  Note, the rudder is controlled with the left joystick or gimbal.  It is set up so that to steer to the left, you move the lever to the left and vice versa to steer to the right.

Next are two pictures of the engine showing the carburetor and needle valve.  The throttle control is also on the left joystick and full forward is full speed and all the way back is idle speed.  The gimbal for the throttle is set up without springs to return it to center position.  The other gimbals or joysticks return to center when the pilot releases the levers.   You have to look close, but the left photo shows the joystick all the way back and the throttle almost closed (idle speed).  On the right the joystick is all the way forward and the throttle is wide open (max speed)

Now, we’ll move on to the elevator movement.  Notice that the right joystick is moved all the way  back for up (ascent) and all the way forward for down (descent),  The elevators are the hinged portions of the horizontal stabilizer and the rudder is the hinged portion of the vertical stabilizer.

The next two pictures show how the ailerons are moved to bank the R/C model airplane to the left and to the right.  On the transmitter, the right hand joystick moved in a right and left direction, control steering by banking the model.  When you want to bank to the right, you move the joystick to the right and the right aileron  moves upward.  Move the joystick to the left to bank the plane to the left and the left aileron moves upward.  It is difficult to see in the picture, but the ailerons move in opposite directions of each other.   To bank to the right, the right wing tip must move down and the left wing tip must move up.   We must always do a pre flight check of all control surfaces and the way I remember which way the ailerons move is for the wing  to tip down in the direction that we move the joystick.

That covers the basics of how the R/C radio controls the model.  We will go into more detail as we get to the point where we are ready to begin flying.  Next time we will take a little break and give ourselves a little time for all the information to “soak” in.  Hopefully, this will help provoke a few questions.

I want to thank my son, Jeremy and his friend, Kristin, for the use of his radio controlled model airplane and for helping with the pictures.  That is his “ever-so-steady” hands that are demonstrating the movement of the joysticks.  Just watch his hands, he is so steady his fingers never leave his hands while flying.

Once you have your model and engine picked out and assembled, you need to start thinking about the radio control system.  One thing I haven’t discussed yet is how the control surfaces( elevator, rudder, and ailerons) control the actions of you radio controlled model aircraft.   Also, we will need to be able to control the engine speed with the throttle.

First, without getting into the complex details of aircraft design, let’s talk about how the control surfaces change the direction of the R/C model airplane in flight.  The upper surface of the wing is actually longer than the bottom surface.  When the air passes over the wing, the shape of the wing ( airfoil ) causes the air to move faster across the top surface than it does across the bottom surface.  This causes greater upward pressure on the bottom of the wing creating lift which supports the weight of the airplane on the bottom surface of the wing.

The ailerons are the two long narrow control surfaces made into the trailing edge of the wing out near the the ends of the wing.  On the smaller models, such as a trainer, they are connected together on one servo so that  they move in opposite directions at the same time.  As one aileron moves up the other one moves down.  It is this action that causes the R/C model airplane to “bank” or turn by  tipping one end of the wing downward while lifting the other end upward.  When the ailerons are returned to the neutral position, the airplane returns to straight and level flight.

The tail section of the plane (often called the tail feathers) stabilizes the plane and controls the up and down movement as well as the left and right movement of the rear end.  The movable part of the horizontal stabilizer is called the elevator and the moveable part of the vertical stabilizer is the rudder.   Both the elevator and the rudder have one servo each in the smaller R/C model airplanes.  If the plane has a nose wheel, it is controlled with the same servo that controls the rudder.  Similar to the way the ailerons work, the rudder and nose wheel move at the same time to enable you to effective control the model when it is moving on the ground.

Before I explain how to install all the radio components, I will see if I can find some pictures that will help you understand how these things work to control the R/C model airplane both on the ground and in flight.  Hopefully, I will have the pictures for the next post.   See you next time and think about this:  In R/C model flying, take-offs are optional, landing is mandatory!

Radio-controlled hobbies for me means R/C airplanes, because that is where I got started and at that time R/C airplanes were mainly what was available.  I was fortunate enough to live in a community that had a well established radio controlled airplane modelers club.

    I joined the club after purchasing a kit and started building it.  I soon realized that the kit I had purchased was not only  very difficult to assemble, it was not designed to be a trainer.  I got acquainted with one of the members of the club and he suggested a different model and was willing to work with me all through the building and setup process.  Consequently, I was successful in getting my first model up and flying without any accidents.   This is why I emphasize the advantage of finding an experienced modeler to help you get started.

    I will cover some of the things you need to consider when selecting the engine for your radio controlled model airplane.  First, the manufacturer of the kit or model will have suggestions as to the size and sometimes even the brand and model of the engine that the R/C airplane was designed around.  If you wish to experiment with something different than what is specified by the manufacturer, proceed with caution and get help from your local expert.

The weight of the engine, the physical size, the power rating, and the required propeller size and pitch can greatly affect the balance and thus, the overall performance of the model.  This is not to say that you shouldn’t do your own experimenting, because modelers have been able to improve engine performance and therefore achieve greater overall performance of the aircraft.  But, it is probably advisable for beginners to stick to the basics.

Two-cycle versus four-cycle engines is a controversial subject and it has been since they started making the 4-cycles somewhere in the late 1970′s to the early 1980′s.  The 2 cycle engines have been around for a lot longer and they have been proven very reliable and many models were designed around them.    The 2 cycle or as some folks say “2 stroke” engines run at a higher rpm than the 4 strokes.  Some R/C fliers believe the 2 cycle engines respond quicker to throttle changes.  They also are noisier and in some areas it is a requirement to have them be muffled to reduce noise pollution.  The performance of the time proven 2 cycle engine is very predictable and reliable when the engine is properly  “broken in”  and tuned.  We will investigate how to break in and tune the engine as we get closer to flight time.

    Generally speaking, at least for R/C model planes, the 4 strokes are usually sized bigger than the 2 stroke.  For, example, if the model maker specified a .45 sized 2 stroke for a certain model, you would probably use a .60 size 4 stroke.  However, the 4 stroke will move the plane the same as the smaller 2 stroke by swinging a bigger propellor at a lower rpm.  This gives you the advantage of having a quieter and more realistic sounding model.  They do require a little more technical ability to tune up and maintain.  You will have to decide on which seems to best fit your particular situation.    

Always keep safety in mind.  One of the things I strongly reccomend to consider when selecting the engine is to get one with a remotely adjustable needle valve.  Originally, they all had the needle valve adjusting screw at the front of the engine.  That required your fingers and thumb to be very close (within 1/2 inch) to the spinning prop.  These engines need to be adjusted when running at full throttle and many times people have had their knuckles nipped by the prop.  Nowadays, a lot of manufacturers are mounting the needle valve at the back end of the engine making it much safer to tune.  Another thing you may need to consider is whether the engine has a built-in fuel pump or if it is gravity fed.  Usually for a trainer, a gravity fed fuel system is adequate, but for a high-performance aerobatic or 3D model you may benefit by having a positive pressure fuel system. 

    One last thing on getting the correct size engine for your model.  Radio controlled model aircraft are usually built according to the size of the motor or engine and it is advisable to follow the model manfacturers instructions for sizing and installion.

    Till next time think about what has been covered so far and and check the earlier blog posts just for review.  I have covered a lot of information and I don’t want you to get overwhelmed.   I encourage all readers to comment on the posts and make suggestions, ie, am I missing anything, are the posts to detailed, not detailed enough, etc.  I want to make your experience with this blog as friendly and informative as possible.