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e) Trimming the model aircraft
Use the trimming function if the model fails to fly straight ahead with reduced motor power or tends to automatically roll
around its longitudinal axis or fly curves. Since the EPP moulded foam is tough and malleable, you can easily deform
the tail units and wings with little effort.
If you look at your model from behind from some distance, you will immediately notice if the wings or tail units are
crooked or warped. Once carefully deformed in the opposite direction, the material no longer readily goes back all the
way to its original position. There is a certain desirable residual deformation. If necessary, carry out several deforma-
tion manipulations until the model flies straight ahead.
Elevator trim
If the model tends constantly to ascend, you can bend the trailing edges of the two tailplanes downwards and the
leading edges upwards to trigger an elevation rudder effect on the tailplane.
Figure 15
If the model tends constantly to lower the tip of the fuselage, move the flight battery to the rearmost position in the slot.
As a second step, you can bend the trailing edges of the two tailplanes upwards and the leading edges downwards to
trigger an elevator effect on the tailplane.
Figure 16