Multiplex FunJet 2 Notice De Montage page 16

Assembly instructions
19. Determining the center of gravity
In order to achieve stable flight characteristics, your FunJet ULTRA,
just like any other aircraft, must be in equilibrium at a certain position.
Assemble your model, making sure it is ready to fly, and insert the drive
battery.
There are half-spherical markings on the underside of the wing.
EN
Using your fingers as support, pivot the model horizontally. Corrections
can be carried out by moving the drive battery. If the right position has
been found, mark the battery box accordingly to ensure the battery is
always in the same position. Fig. 18
20. Fine tuning
The excellent flight characteristics of the model can be optimized by fine
tuning the center of gravity and down thrust. The motor mount is also
useful here, as the down thrust can be adjusted and the adjustment result
can be read off a scale.
First fly "full throttle" and trim the model exactly. If you then turn off the
motor, a steady descent must take place. If the model becomes slow, the
down thrust is too strong - reduce the down thrust. If the model continues
to "shoot", the down thrust is too low - add a little down thrust and trim
"up" before the next start. Repeat this procedure until the model makes
a perfect descent after reducing the throttle and goes straight ahead
spontaneously, if necessary climbing slightly, when "accelerating again".
When adjusting the center of gravity, fly straight ahead at full throttle, flip
the model over. If the center of gravity is correct, you have to press about
15-20%. If you need to press less, the center of gravity is too far back - if
you need to press more, too far forward. In almost all cases, the center of
gravity has to be corrected by shifting the battery. If it is not enough, some
trim weight may also be necessary. After fine tuning the center of gravity,
you may have to repeat the down thrust adjustment.
21. Something for the visual appeal
The kit includes multi-colored decal sheets 2 A, B, C, D.
Position the individual elements according to our template.
22. Initial flight
Carry out a range test and make sure all the rudders are running in the
correct direction and are in the neutral position.
The model is started at 'half speed' from your hand - always against the
wind.
If necessary, have an experienced launcher start the model.
The model is started at 1/2 or 3/4 speed diagonally upwards (20-30°).
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