Wing section
The wing features a cambered airfoil section over which the air fl ows when the model is fl ying. In a given period of time the air
fl owing over the top surface of the wing has to cover a greater distance than the air fl owing under it. This causes a reduction in
pressure on the top surface, which in turn creates a lifting force which keeps the aircraft in the air. Fig. A
Centre of Gravity (CG)
To achieve stable fl ying characteristics your model aircraft must balance at a particular point, just like any other aircraft. It is abso-
lutely essential to check and set the correct CG position before fl ying the model for the fi rst time.
The CG position is stated as a distance which is measured aft from the wing root leading edge, i.e. close to the fuselage. Support
the model at this point on two fi ngertips (or - better - use the MPX CG gauge, # 69 3054); the model should now hang level. Fig. B
If the model does not balance level, the installed components (e.g. fl ight battery) can be re-positioned inside the fuselage. If this
is still not suffi cient, attach the appropriate quantity of trim ballast (lead or plasticene) to the fuselage nose or tail and secure it
carefully. If the model is tail-heavy, fi x the ballast at the fuselage nose; if the model is tail-heavy, attach the ballast at the tail end
of the fuselage.
The longitudinal dihedral is the difference in degrees between the angle of incidence of the wing and of the tail. Provided that you
work carefully and attach the wing and tailplane to the fuselage without gaps, the longitudinal dihedral will be correct automatically.
If you are sure that both these settings (CG and longitudinal dihedral) are correct, you can be confi dent that there will be no major
problems when you test-fl y the model. Fig. C
Control surfaces, control surface travels
The model will only fl y safely, reliably and accurately if the control surfaces move freely and smoothly, follow the stick movements
in the correct "sense", and move to the stated maximum travels. The travels stated in these instructions have been established
during the test-fl ying programme, and we strongly recommend that you keep to them initially. You can always adjust them to meet
your personal preferences later on.
Transmitter controls
The transmitter features two main sticks which the pilot moves to control the servos in the model, which in turn operate the control
surfaces.
The functions are assigned according to Mode A, although other stick modes are possible.
The transmitter controls the control surfaces as follows:
Rudder (left / right)
Elevator (up / down)
Throttle (motor off / on)
Unlike the other controls, the throttle stick must not return to the neutral position automatically. Instead it features a ratchet so that
it stays wherever you put it. Please read the instructions supplied with your radio control system for the method of setting up and
adjusting the transmitter and receiving system.
A
Lifting force
C
E
Fig. D
Fig. E
Fig. F
α
B
D
F
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