RTFs are very popular because there's little to do but charge
the battery, strap the wing into place, and turn the radio on. These
very durable models are often made of formed plastic and rigid foam.
Some RTFs come with conventional controls (rudder and elevator), while
others have more rudimentary controls that simply turn the plane left or
right. Some feature throttle control, while others have an uncomplicated
arming switch that turns the motor on and runs it until the rechargeable
battery's power has been used up. Several newer designs even come with
spare props and wings so you don't have to go back to the hobby shop if
you break something.
Regardless of your modeling experience level, there are several
backyard flyers to choose from. Stop at a local hobby shop, and see what
best suits your fancy.
Basic equipment. To assemble most builder's kits and ARFs, you
will need some basic shop tools. These include: small flat-head and
Phillips screwdrivers, a hobby knife with several new blades, long-nose
pliers, an Allen-wrench set, a small adjustable wrench and sandpaper.
For some of the more involved models, where you'll need to install the
motor and electronic speed control (ESC), you should have a small, 30W
soldering tool, some soldering flux and 60/40 rosin-core solder. Most
models come with instructions that specify the supplies and tools
required to build the model. To save time and effort in the long run,
check the instructions and get all your equipment together before you
start building your model.
Flight Simulators
A very good learning tool for any RC pilot is an RC flight simulator
computer program. Advances in personal computers and microprocessors
have enabled simulators (sims) to evolve to a very high degree of
realism. Although not a total replacement for real-world flight
training, virtual training in the comfort of home does help teach the
student pilot's thumbs and eyes to work together. Because of his
practice at home, when the student goes to the flying field and has a
radio in his hands, he will react more quickly. Less “think time” means
more time to correct for piloting errors. Another advantage of flight
sims is that they extend the flying season for those who live in cooler
climates. You can “fly” all winter long and never leave the house.
Several flight sims are available, and they all work roughly in the
same way. The sim presents a model airplane image on the computer
screen, and the plane reacts to your control inputs. Some sims come with
a control box that looks very much like an RC transmitter; other systems
provide an interface that lets you connect and use your own radio. You
can choose from several models provided by the program, or you can
create new models or represent your own.
Most sims offer a choice of flying environments, so you can fly from
a typical flying field, the surface of Mars, or anywhere in between.
Also, you can adjust weather elements such as wind direction, crosswind
velocity and gusts. You can make the flight simulation as easy or as
difficult as you like. Most programs also include a few helicopter
simulations.
By training yourself with a flight sim, you can greatly reduce the
time it will take for you to learn how to fly your model. You can also
continue to fly even when the weather isn't cooperating. Bring the
excitement of RC flight indoors and have fun.
Before Flight Training
There are some basic things you'll need to know after you've built your
model and have made sure that everything is working properly. Let's call
it “Before flight training.” If you have just built your first backyard
flyer, the best way to learn how to fly is by asking an experienced
friend to teach you. If, however, you want to learn to fly by yourself,
here are some things to be aware of.
Radio frequency. The radio that controls
your model is on a specific frequency, and when you switch it on, it
transmits a continuous signal. If someone else is using the same
frequency as you are, the two radios will interfere with each other and
cause both of you to lose control. Before you go out and fly, you should
make sure you are at least three miles away from an established RC model
flying field. You can ask the people at the local hobby shop whether
there is a field nearby, or you can check with the Academy of Model
Aeronautics (AMA) at
www.modelaircraft.org for a list of RC clubs in your state.
Flight direction. Up and down are easy; no matter in which
direction your model is heading, up will always be up and down will be
down. Left and right are another matter. When you and your model are
both facing in the same direction (i.e., the model is flying away from
you), your left and right will be the model's left and right. If you
move the stick to the right, your model will turn right and so on. But
when the model is facing toward you, i.e., flying back toward you, its
directions, relative to your stick command, will feel as though they
have been reversed. When you push the stick to the right, the model will
turn to its right, but that will be to your left! This is known as
“returning control reversal,” and if you are not prepared for this
condition, it will claim your new model.
If we don't turn the model, it will soon be out of sight. To keep
your model in the flying area, you have to think constantly about which
way you want to turn your model. Holding the turn too long or turning in
the wrong direction will cause it to spiral into the ground. When the
model is coming toward you, pushing the stick toward the side with the
lower wingtip will level the wings and prevent the turn from becoming so
tight that you get confused.
Wind. The direction and strength of the wind have a great
effect on your model. It's best to fly early in the morning and late in
the afternoon when the sun is low and the wind is generally at its
calmest, and this gentle air is good for beginners. Look at the trees
around your flying area and note how much the wind causes the leaves and
branches to sway. Is there a flagpole nearby? How much is the flag
waving in the breeze? In a heavy wind, you may find you have no control
at all over the model and it may be carried away by the wind. For your
first few flights, the less wind, the better.
Launch. Always launch the model into the wind. Face into the
wind and hold the model above and slightly in front of you. Launch it by
taking a few quick steps and lightly tossing it into the wind with its
wings level. Release it with its nose pointing at the horizon or
slightly below it. Don't throw it upward at a high angle; it will stall
and lose lift.
Landing. When flying, try to keep the model upwind from you.
If you allow it to get too far downwind, at the end of its flight, it
may not have enough power for you to bring it back to land. When it is
time to land, keep the wings level and land straight into the wind.
Throttle back and allow the model to descend gradually; don't dive
toward the ground, or you'll increase the model's speed and make it
difficult to land gently. Just as the model is about to touch down,
gently apply up-elevator to keep its nose up slightly. Downwind and
crosswind landings are difficult and may cause you to damage the model
when it touches the ground. Whenever possible, land into the wind, not
going with it. Landing upwind allows the model to settle onto the ground
gently.
Your flying area. It may seem obvious, but you really need to
evaluate the size and condition of the area in which you want to fly
your model. Do you want to fly it in your backyard or at a local park?
Is there a school nearby with a wide-open soccer field that's calling
your name? The size of your flying area will dictate the size of the
model airplane that can be safely flown there. Here's why:
The size of your model and how much it weighs will affect how quickly
or slowly it can fly. Its speed then affects how quickly you can turn
it, and the turning radius determines the size of the airspace you need.
Yes, I said airspace—not the size of the field. Models can fly great
distances away from you, and you could fly it so far away that it would
be difficult to see and to control. Look for a flying site that allows
you to keep the model close without your running it into trees or
buildings. And for safety reasons, don't fly it over a road with
traffic.
Most backyard flyers have small landing gear and wheels, so they
can't taxi and take off from the ground. For this reason, you'll have to
hand-launch the model (or have a friend hand-launch it for you). After
the model has used up its battery charge, it's time to land. Small
models can take off from hard, paved surfaces such as large parking
lots, but remember that if you crash your model into a hard surface,
it's more likely to be damaged. The safest areas to fly from are grass
fields; tall grass is also great, especially if you're teaching yourself
how to fly. Tall grass will cushion the model when it lands and could
prevent it from being damaged in a hard return to earth.
Establish a “flightline.” When flying in an open field, it's
good practice to define an imaginary safety line that helps separate
your model from the people who are watching you fly. Don't fly the model
in a circle around you; keep the model's flight path in front of you,
and have observers stay behind you. This gives an added margin of safety
for everyone.
Small, slow, lightweight models. These can easily be flown in
an area that's roughly the size of a baseball diamond. This is the
minimum area in which to fly a model safely. Compare your backyard or a
nearby vacant lot to a Little League diamond, and ask yourself whether
you can safely fly there. You should be able to hand-launch the model
and fly a circular course or a figure-8 pattern. If your model is very
light and agile, you will, in time, be able to fly it between trees and
over fences, but in the beginning, make sure your flying area is clear
of obstructions.
Slightly heavier models. Because they fly a little faster,
these planes will need an area that's roughly the size of the baseball
diamond and the outfield. Sporting complexes often have two diamonds in
one field, and this is ideal. Of course, you'll have to wait for a time
when the home team is not practicing or striking out the visitors. If
you're lucky enough to have a backyard this big or you live near a
vacant lot, you're all set. Please, don't fly your model over other
people; it can be distracting and is definitely unsafe.
Bigger and faster models. These models should be flown in a
football field or a soccer field. Typically, you should stand on the
50-yard line so you have a lot of space all around you. Large local
parks may have this much open area, but regardless of where you fly,
before you throw your model into the air, ask someone whether or not you
can do so. It's the polite thing to do. People who are walking dogs and
kids who are playing nearby are all attracted to model airplanes, so be
aware of what's going on around you. Let people know you're out there;
be seen and have fun.
Before you fly
Well, you're almost there; you've built and prepared your model and
you've found a great place to fly it close to home. Is there anything
left to do before that first flight? Yes; you should be aware of a few
details that can make the difference between your having a great flight
and a bad one. Let's see what's left.
Balance. Did you balance your model? Did you
check to see whether the model's center of gravity (CG) is in the proper
location? Every airplane kit instruction booklet should explain where
the balance point should be. For a straight wing, this point will
usually fall somewhere between 1/4 and 1/3 of the chord back from the
leading edge (LE). With a sweptback wing, the CG will be farther
rearward; again, check the instructions.
To check the model's balance point, install the receiver (RX) and the
battery pack and attach the wing to the fuselage. Support the wing with
your fingertips—near the fuselage sides—and test the model's balance;
move the receiver and battery until it balances level or slightly nose
down. This is the balance point, and it should match that specified on
the instructions. If it doesn't, try moving the RX and battery again; if
that doesn't work, add a little weight to the nose or the tail until the
model balances where it should. This is vital. A nose-heavy model will
probably fly satisfactorily, but a tail-heavy one might not be
controllable.
Control direction. One of the most common causes of a
first-flight crash is that a model has its controls hooked up backward.
Test your controls to make sure that they don't bind and that they move
the control surfaces (rudder, ailerons, etc.) in the proper directions.
Turn the transmitter (TX) on first and then turn on your model's RX.
Make sure the TX's trim levers are centered, and check the control
surfaces to make sure that they are straight and in their neutral
positions. While facing in the same direction as your model, move the
control stick to the right; the rudder should also move to the right. If
your plane has ailerons, when you move the stick to the right, the right
aileron should move up and the left aileron should move down. When you
pull the elevator stick back toward you, the elevator should move
upward; it should move downward when you push the stick away from you.
This is also a good time to check the throttle and to make sure that
the motor is turning in the correct direction. When the throttle is
pulled all the way back, the prop should not move. As you push the
throttle stick forward, the prop should respond proportionally and
should blow air back over the model. If your airplane has only an arming
switch (no throttle), make sure the prop spins in the right direction
(counterclockwise when looked at from the nose of the plane).
Warping. Having assembled the model, make sure that the wing
panels are straight—no twisting or warping. Look at each wing panel from
the tip to the root (toward the fuselage), and make sure their angles
match. If one tip has more positive or negative angle than the other
does, your model will try to turn in one direction or the other.
To fix a warped wing panel, gently twist it into the opposite
position, and then have a helper use a heat gun or a high-wattage hair
dryer to remove the wrinkles in the covering. When the covering has
cooled and the wrinkles have disappeared, release the panel, and it
should be straight.
Check to make sure that the tail surfaces are also free of warps and
that the wing and horizontal stabilizer are properly aligned.
That's about it. Make sure your RX and drive batteries are fully
charged and that the TX batteries are also in peak condition. Check the
little light indicator or the meter on the TX face and make sure your
radio system is working properly. Have fun.