Model menu
Auto-rotation
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19.4 AUTO-ROTATION SETTINGS
This option is used for entering the settings for auto-rotation,
so that the motor either stops or idles when the ‘Auto-rotation’
flight mode (TH-HOLD) is selected, regardless of the position
of the throttle stick. Two independent settings - motor off and
idle - can be entered. It is advisable to use the ‘Idle’ mode for
practising auto-rotation landings. Either of the auto-rotation
modes can be activated using switches which you can select
freely.
With the ‘Helicopter’ model type already selected, mark this
option in the Model menu. The screen now looks like this:
The screen displays two separate frames for the auto-rotation
settings, i.e. ‘motor stopped’ and ‘idle’. In the left frame you
can enter the settings for a cut (stopped) motor, while the right
frame contains those for the motor at idle. Both sets of values
are entered in exactly the same way. The only item which dif-
fers is the term ‘Off Pos.’ for motor cut, which changes to ‘Idle
Offs.’ for the idle option. In the first display the Offset point for
automatic mode is displayed in graphic bar form. The follo-
wing description therefore covers both frames, but we will
concentrate on the ‘Motor off’ mode in the following example.
The first step is to activate this option in the familiar fashion:
simply mark the Status line in the standard way, and the dis-
play changes from ‘INA’ to ‘ON’. After this you can select
‘Glob’ or ‘Sepa’ mode.
You can now enter the Auto-rotation mode in the second line.
Two different modes are available:
Manual:
Manual mode
Auto:
Automatic mode
In manual mode the auto-rotation flight mode is only triggered
when a (freely selectable) switch is operated. In automatic
mode, the auto-rotation flight mode is triggered by the position
of the throttle stick. In the latter case it is necessary to define
the trigger point: move the throttle stick to the desired posi-
tion, and mark the ‘Off Pos.’ field. The software stores the trig-
ger position, and displays it as a percentage value in the
appropriate field and in bar form on the right of the display
frame.
This screen shot shows a set-up with an automatic position
programmed for both ranges: ‘Motor off’ and ‘Idle’.
The next step is to set the carburettor position for auto-rota-
tion, in the form of a percentage figure in the ‘Off Pos.’ or ‘Idle
Offs.’ line. In ‘Off’ mode the motor is shut down completely, so
the servo travel should be set accordingly. In ‘Idle’ mode the
carburettor setting should be selected to move the motor to
idle at a reliable but not excessively high speed. In both cases
mark the field, and enter the required setting using the arrow
buttons. The adjustment range is 0% to 50% for ‘Off Pos.’ and
-30% to +30% for idle pre-set.
Now it is time to select the transit speed of the throttle servo
when the auto-rotation state is triggered; this is entered in the
‘Speed’ line: mark the appropriate field and use the arrow but-
tons to enter the setting as a numeric value. Please note: the
higher the number, the more slowly the servo moves to its
commanded position. The maximum value (27 increments)
corresponds to a duration of nine seconds.
The process is concluded by assigning an auto-rotation trigger
switch. Mark the field, and the switch select menu appears.
You can now set your preferred switch and its direction of ope-
ration.
In this menu you define the speed at which the throttle servo
moves to its auto-rotation position. This is usually required to
occur quickly, so the setting shown in the screen shot is cor-
rect.
The speed with which the throttle servo takes up the individual
positions in each flight mode is set under ‘Delay’ in the ‘Flight
mode’ menu.
This setting can apply either globally (all flight modes) or for
each flight mode separately.
It is also absolutely essential to activate the Auto-rotation flight
mode in the FLIGHT MODE menu, since that is where you
select the speed at which the system recovers from the auto-
rotation position, e.g. when you switch back to the ‘Aeroba-
tics’ flight mode.
The Download area of the robbe website includes a pre-pro-
grammed model helicopter complete with a description of the
settings.
Please ensure that the Auto-rotation function is switched off
before you attempt to start the motor.
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