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190 Detail program description - Helicopter mixer / Auto-rotation settings

 Auto-rotation setting

Auto-rotation permits both full-size and model 
helicopters to land safely in a crisis, e. g. if the motor 
should fail. Moreover, if the tail rotor should fail, 
cutting the motor and landing using auto-rotation is 
also the only possible way to avoid a high-speed, 
uncontrollable rotation around the vertical axis 
and a resulting catastrophic crash – which is why a 
switchover TO the auto-rotation phase takes place 
immediately.
When the switchover to the auto-rotation phase is 
made, the Helicopter mixer menu screen changes as 
follows:

Pitch

–90%

Tail rot. offset AR

0%

Thr. position AR

Gyro suppression

Swashplate rotation

Swashplate limiter

0%

0°

AUS

Œ

Gyro offset

0%

Autorot

During auto-rotation fl ight, the main rotor is no longer 
driven by the motor but only by its own momentum and 
the the airfl ow through the rotor plane during descent. 
Since the energy stored by a rotor kept spinning in this 
way is rapidly consumed if the helicopter fl ares, pilots 
must not only have experience in handling helicopter 
models but must also consider carefully how the 
relevant functions should be confi gured.
The advanced pilot should therefore practice auto-
rotation landings at regular intervals. Not only to be 
able to demonstrate mastery of the maneuver at 
competitions, but also to ensure the pilot can can 
land the helicopter undamaged from a great height if 
the motor should fail. For this purpose, the program 
provides a range of adjustment options designed to 
help the pilot fl y a motorized model in its unpowered 

state. Note that the auto-rotation settings comprise a 
complete seventh fl ight phase, which provides access 
to all the fl ight phase- specifi c confi guration options, 
and to trims, collective pitch curve settings, etc., 
in particular. The following functions have special 
features not present in the powered fl ight phases:

(Collective pitch curve (C1 

¼ Pitch))

In powered fl ight, the maximum blade pitch angle is 
limited by available motor power. In auto-rotation, 
however, it is limited only by the point at which airfl ow 
ceases over the main rotor blades. Greater maximum 
collective pitch must therefore be set to ensure 
suffi cient thrust when fl aring the helicopter even as 
rotational speed is falling off. To do so, briefl y tap 
the center 

 key of the right touch pad to switch 

to the "Pitch" graph page and then use the joystick 
to move the vertical line to point "H". Start by setting 
a value that is about 10 to 20 % greater than your 
"normal" maximum value for collective pitch. Initially, 
however, do NOT set a value that is considerably 
greater than for normal fl ight, since, if this is done, 
the behavior of the collective pitch controls may then 
be very unfamiliar following the switchover. Indeed, 
there is a danger that the pilot will oversteer during 
the fl are and the model will balloon: this will case the 
rotor speed to collapse at a considerable altitude and 
the model will then crash to the ground. The value 
can always be readjusted later after fl ying some test 
auto-rotations.
The minimum value for collective pitch can differ 
from that set for normal fl ight. This depends on the 
pilot's usual style for normal fl ight. For auto-rotation, 
however, always set a suffi ciently generous minimum 
value for collective pitch at point "L" to ensure 
the model can be brought out of forward fl ight at 
moderate speed into a descent at an angle of around 
60 … 70 degrees when collective pitch is reduced to 
a minimum. If, like most helicopter pilots, you have 
used this kind of setting for normal fl ight anyway, then 

this value can simply be transferred.
If, however, you normally let your model "fall" at a 
shallower angle, then you should increase the value 
at point "L", and vice versa.

Approach angle for 
various wind conditions

Approach angle

in moderate 

wind

no wind

45°

60°

75°

in strong 

wind

As a rule, the collective pitch stick itself is not 
positioned right at the bottom of its travel for auto-
rotation. Instead, it is typically between the hover 
position and the bottom end-point. This offers the 
pilot an option for further adjustment, e. g. via pitch 
inclination through pitch-axis controls.
The approach can be shortened by pulling back 
slightly on the pitch-axis joystick and gently reducing 
pitch or by extending the approach by pushing 
forward on the pitch-axis joystick and carefully 
increasing pitch.

Although pilots will be expected to cut the glow 
motor completely during competitions, This is rather 
inconvenient during training sessions because the 
motor must be restarted after every practice auto-
rotation landing.
Therefore, for training sessions, set this line's value 
such that a combustion motor is held at a safe idle 
without the clutch engaging during the auto-rotation 
phase; electric drive systems should be set safely to 
"Off".