Beginners' Guide

First Model

Some people would consider a glider as the obvious choice for the first model.
Although a glider normally flies slower and is supposed to be more forgiving,
I think that is just a matter of taste.

Being a skilled glider pilot does not necessarily mean being also a skilled
powered aircraft pilot and vice-versa.

Assuming that a powered model was chosen, the beginner is advised to start
with a so-called trainer.

This type is usually a high wing aircraft model with nearly flat bottom airfoil
that produces high lift, permitting slow landing speeds without stalling.
It also has some dihedral angle to give a good lateral stability.

However, a flat bottom high wing with dihedral is more sensitive to crosswind gusts, so the
fist flights should be done during calm weather.

A beginner should avoid wings with too sharp leading edges, as it will worsen the stall characteristics

A well-rounded leading edge is therefore preferable, as it better conveys the
airflow onto the upper wing surface allowing higher angle of attack at low speed.

A trainer model should not be too small, as it would be difficult to assemble and
maintain and would be more sensitive to strong winds.

 It should not be too large either, as it would be difficult to transport, require a larger
 flying field and would be more expensive.

A reasonable size is about 150cm wingspan (60 in) with a high aspect ratio,
which means the wingspan being about 5.5 times the wing chord.

A square wing is advisable, as it distributes the weight of the aircraft evenly
over the entire surface of the wing.

In order to allow a reasonable low landing speed without stalling, the wing
loading should not be greater than about 60g/sq.dm (19-oz/sq. ft).

Wing loading is the aircraft's weight divided by the wing area.
Some degree of wing washout also improves the stall characteristics.


The basic parts of a trainer model:

Engine - provides the power to rotate the propeller.

Propeller - (also Prop) is attached to the engine's shaft to convert rotational motion into thrust
and speed, which depends on the Prop's diameter, pitch and the Engine's power.

Spinner - streamlined part that covers the end of the Prop shaft.

Fin - (also Vertical Stabilizer) provides directional stability (stability in yaw).

Rudder - moveable part fitted to the Fin's trailing edge is used to change the aircraft's direction.

Stabilizer - (also Horizontal Stabilizer or Stab) provides longitudinal stability (stability in pitch).

Elevator - moveable part fitted to the Horizontal Stabilizer’s trailing edge is used to make
the aircraft climb or dive.

Ailerons - movable parts on both sides of the wing, are used to make the aircraft roll about its
fore - aft axis. When one aileron moves up the other moves down.

Wing - provides the aircraft's main lifting force.

One may build a model aircraft based on drawings (plans). This requires some
building skills and time and effort to find out and gather the materials needed
for the construction.

An easier approach (albeit more expensive) is buying a kit of parts.
There are many kits on the market with different levels of prefabrication depending
on their price.

The cheaper kits have most of parts included, but some pieces come either pre -
cut or printed on sheets of wood, so the builder is expected to do some extensive
job, such as to cut out the fuselage formers and wing ribs, glue the parts together,
apply the covering material, etc.

For those who are not so keen on construction, there are almost ready to fly (ARF)
kits with an extensive prefabrication, requiring one or two evenings to assemble.

There are also ready to fly (RTF), which normally come complete with the power
plant and radio preinstalled.

First Flight

It is highly recommended to have an experienced instructor beside you during
your first flight; however, it is not impossible to be succeeding by doing it alone.
Max wind speed recommended is 5 - 8Km/h (3 - 5mph) including gusts.

Check the CG location with empty fuel tank by supporting the model with your
fingertips underneath the wings.

Find the position where the fuselage gets level or its nose is pointed slightly
downwards.

Transmitter range check should be performed on the ground before each flight.

This is usually done with the Transmitter aerial collapsed. The control surfaces
should respond without glitch at a distance of about 80 meters (263ft).

This distance is only an approximately guide line, as the actual range may vary
depending on the environment.

The effective range may only be half of this value if located at mountain bowl site
or close to a public radio transmitter, radar station or similar.

The range may suffer adverse effects if the receiver aerial is close to metal parts
or model components reinforced with carbon fiber.

Some transmitters allow the aerial to be totally collapsed inside a metal case,
which also may reduce the radiation.

In this case, the lower section of the aerial should be extended during the test.

The check should be repeated with the power system running, alternating the
throttle setting between idle and full-throttle.

The range will be much higher when the model is in the air, normally about 1Km
or as far as one can see the model.

Take-offs

If you hand launch your model, throw it against the wind horizontally and
straight ahead, not up.

If you take-off from the ground, taxi the model towards the wind and let the
model gain ground speed before applying elevator.

Once in the air try to climb at a very small angle, not abruptly upward, which
would cause loss of airspeed and stall.

The model is more sensitive to the motor torque effect during the relatively
low take-off speed and may begin to turn left (or right).

Use the rudder or ailerons to prevent the model from turning during the climb
stage, otherwise the model may initiate a spiral dive.

Do not try any turns until the model has gained speed and reached a "safe
altitude".

First time fliers should seek help from more experienced filers, getting the aircraft
trimmed for straight and level flight.

A great way to familiarize yourself with the controls and the function of the aircraft is to find an area at the flying field where you can practice doing a figure eight pattern going in both directions.

Be very gentle with the controls and practice gentle turns high in the
air before you try to land, it is a good practice to make several approaches before you actually try a landing.

To prevent losing altitude when turning the model, just give little up elevator
at same time you make a turn.

Try to keep the model in sight and do not fly too high or too far away.

You may reduce the throttle while high in the air so you may get an idea how
the model behaves at low speed.

To prevent getting confused about which way to turn when the model flies
towards you, turn your back to the model slightly while keeping watching it,
so you can imagine "right" and "left" from the model's point of view.

Some trimming may be needed in order to reduce or eliminate roll, bank and/or
pitch tendencies.

A flat bottom wing often tends to "balloon" up into the sky, keeping climbing
when full throttle is applied. This may be reduced during the flight by adjusting
the elevator trim or by reducing the throttle.

In worst cases, it may be needed to increase the motor's down-thrust angle
and/or decrease the main wings incidence angle.

Landings:
Reduce throttle to about half so you have to slightly pull up the elevator to keep
the altitude.

Turn the model towards the wind and let the model sink gradually towards the
landing area by easing the elevator.

During the last fifteen to twenty meters (45 to 60 feet) of descent, (which
depends on the model's characteristics) you should idle the throttle.

The model will start sinking at a higher rate now. Try to keep the model in a
shallow dive and do not use the elevator to gain altitude or to prolong the
flight at this stage, otherwise stall is likely to occur.

Just keep a downward attitude throughout the final approach in order
to maintain the airspeed.

The higher the wing loading, the steeper the approaching angle may be
however, it is not recommended approaching angles greater than 45 degrees.

If you notice that the model is sinking too fast or is too low to reach the landing
field - just increase the throttle first before applying elevator to maintain or gain
altitude to prolong the flight or to repeat the landing approach.

Pull up the elevator slightly about 30-60cm (1-2 ft) before the touchdown so
that the propeller or nose gear does not hit the ground.

Be prepared to repeat unsuccessful landings several times, since it is often a
matter of trial and error before one gets used with how the model behaves.

Do not try to land in a specific spot, avoid turns when the model is flying low
or at low speed. Just let your model glide into the ground straight-ahead.

Avoid the proximity of buildings, roads and electric power lines.
Do not fly close to or towards buildings, public highways, people or animals.

The bigger the field for your first flight, the greater will be your chances
for success.

It is advisable to join the nearest model aircraft club there you may meet
experienced flyers who can assist you with your first flight and landing.

Have fun!