HITEC Sky Scout (KIT) - Manual (Page 21)

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Fly high with Hitec
Appendix A: The Basics of Model Flying
The basics of model flying
Any aircraft - whether model or “man-carrying” - can be controlled around three primary axes: the vertical axis, lateral axis and longitudinal axis.
Operating the elevator produces a change in the aeroplane’s flight attitude around the lateral axis (pitch).
Giving a rudder command turns the model around the vertical axis (yaw).
If you move the aileron stick, the model rotates around the longitudinal axis (roll).
All three axes can be controlled regardless of the aeroplane’s flight attitude.
All aircraft are subject to external influences, such as turbulence, which tend to disturb the aircraft, causing it to deviate from its intended flight path; the
pilot’s task is then to apply control commands so that the model continues to fly in the desired direction.
The power system (motor and propeller) provides control over rate of climb and speed. The rotational speed of the motor is infinitely variable using the
speed controller, which follows your control commands from the transmitter.
The important point to note is that pulling up elevator by itself causes the model to climb, but only until it reaches its
minimum airspeed. The aero-
plane’s ability to climb at different angles depends on the power of the motor. If the model’s speed falls below its minimum airspeed, it tips forward and
dives: this is known as stalling. This occurs when the airflow which generates the lift required to keep the aircraft in the air is no longer attached to the
wing, and the lift collapses.
The Sky Scout is designed in such a way that it exhibits very docile stalling characteristics, and loses very little height when it does stall. In this situation
it drops its nose, immediately picks up speed, and is very soon under the pilot’s control once more.
If you are a beginner to model flying, we recommend that you initially control the Sky Scout using rudder and elevator only.
To turn the model (initial turns and circles), use the rudder to set up a slight angle of bank, then apply gentle up-elevator to avoid the nose dropping dur-
ing the turn. Always try to turn away from you at first.
Once you have mastered basic control of the Sky Scout, it is time to try the ailerons. However, this does not mean that you can afford to forget the rud-
der. A smooth turn, i.e. one which makes efficient use of the airflow, is always flown best by co-ordinating rudder and aileron commands. This is a basic
skill required to fly any model aeroplane smoothly and accurately.
Without this level of co-ordination the Sky Scout will not fly so efficiently, although it is very tolerant of such abuse. However, if you concentrate on learn-
ing the art of flying smoothly right from the outset, you will find it much easier to control more demanding models at a later date, and will be able to avoid
many a critical situation.
Concentrate constantly on moving the sticks slowly and gradually.
Abrupt, jerky movement of the transmitter controls often places the model in flight situations from which the beginner is unable to escape.
If this should happen, it is generally better simply to let go of the sticks and switch the motor off.
Wait a few moments until the model has “calmed down”, and you will then find it easier to regain full control. If you cannot avoid a crash, at least the
motor is stopped, minimizing the energy which has to be dissipated through the impact, and thereby limiting damage to the airframe.
As a beginner you are bound to find it difficult to
steer in the correct direction when the model is flying towards you. Learn this rule by heart: the
stick must be moved to the side where the “danger” lurks, i.e. move the stick towards the low wing, and “prop it up”.
We suggest that you learn these suggestions in the period before the first flight, so that you are not surprised by the model’s behaviour
when you are actually flying!
Wing section (airfoil)
The wing has a curved (cambered) cross-section, known as an airfoil, over which the air flows when the model is flying. In a given time the air above
the wing covers a greater distance than the air below the wing. This results in a reduction in pressure over the top surface of the wing, generating an
upward force (lift) which keeps the aircraft in the air.