flight battery). If this is not sufficient, the correct quantity of ballast (lead or modelling clay) should be fixed securely to the nose or
tail of the fuselage. If the model is tail-heavy, fit the ballast at the fuselage nose; if it is nose-heavy, attach the ballast at the tail end
of the fuselage.
Neutral point
The neutral point of an aircraft is the point at which the aerodynamic forces are in equilibrium. If an aeroplane flies in a stable
attitude, then its neutral point is always aft of the Centre of Gravity. Any aircraft whose Centre of Gravity is aft of the neutral point will
be inherently unstable in the air. Manual control of an aircraft trimmed in this way is impossible; it requires a computer system
for stabilization and control.
Longitudinal dihedral
This term refers to the difference in incidence between the wing and the tailplane. Provided that you fit and secure the EasyStar
II's wing and tailplane to the fuselage as stated in these instructions, then the longitudinal dihedral will automatically be exactly
correct. If these two settings (centre of gravity and longitudinal dihedral) are correct, you will encounter no problems when flying
your aeroplane, especially at the test-flying stage. Fig. C
Control surfaces and control surface travels
The model can only fly safely and precisely if the control surfaces are free-moving, operate in the correct "sense" (direction
relative to stick movement), and are set up to deflect by the appropriate amount. The control surface travels stated in the building
instructions have been established by a test-flying programme, and we recommend that you adopt these settings initially. You
may wish to adjust them subsequently to suit your personal preferences.
Transmitter control functions
The radio control system transmitter is fitted with two primary sticks which cause the servos - and therefore the model's control
surfaces - to deflect when moved. The stated function assignment is correct for stick mode A, but other stick modes are possible.
The following control surfaces are controlled from the transmitter:
The rudder (left / right) Fig. D
The elevator (up / down) Fig. E
The throttle (motor off / on) Fig. F
The ailerons (left / right) Fig. G
The stick which controls the throttle (motor speed) must not be of the self-centring type. It is usually fitted with a ratchet which
operates over the full stick travel. How this setting works you can read up in the operating instructions supplied with your radio
control
system.
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