- First Model
Some people 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's just a matter of taste.
Being a skilled glider pilot doesn't 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 first 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.
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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 Stabiliser) provides directional stability (stability in yaw).
Rudder - moveable part fitted to the Fin's trailing edge, is used to change the aircraft's direction.
Stabiliser - (also Horizontal Stabiliser or Stab) provides longitudinal stability (stability in pitch).
Elevator - moveable part fitted to the Horizontal Stabiliser'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 also 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 some of them even with the radio preinstalled.
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