Reely SKY YAK54 Notice D'emploi page 51

Important information!
If you align the model horizontally and then look at it from the side, you will quickly notice that the rotor is
not exactly vertical to the longitudinal fuselage axle (see figure 13, interrupted line), but slightly slanted.
This is intentional and not a defect of the model or the motor attachment.
To avoid too strong lift at full motor output, the motor of model
plains is usually installed so that the rotor has a slight
„inclination" downwards.
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Figure 13
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