GRAUPNER mx-16 ifs, Programming Manual

Page: 84 / 132

84 Program description: helicopter mixers – model helicopter
The climb setting
The combination of throttle hover setting, collective pitch
setting for the hover and the maximum collective pitch
setting (Point 5) now provides you with a simple method
of achieving constant system rotational speed from the
hover right to maximum climb.
Start by placing the model in an extended vertical climb,
holding the collective pitch stick at its end-point: motor
speed should not alter compared with the hover setting.
If motor speed falls off in the climb, when the throttle is
already fully open and no further power increase is pos-
sible (this assumes that the motor is correctly adjusted),
then you should reduce maximum blade pitch angle at
full defl ection of the collective pitch stick, i. e. the value
at Point 5. Conversely, if motor speed rises during the
vertical climb, you should increase the pitch angle. This
is done on the “Collective pitch” graphic page by mov-
ing the vertical line to Point 5 using the collective pitch
stick, and changing its value accordingly using the rotary
cylinder.
This diagram only shows the
changes to the collective pitch
maximum value.
+100%
-100%
OUTPUT
2 3 4 5 1
Control travel
Hover
point
Now bring the model back to the hover, which again
should coincide with the mid-point of the Ch 1 stick.
If you fi nd that the collective pitch stick now has to be
moved from the mid-point in the direction of “higher”,
then you should correct this deviation by slightly increas-
ing the collective pitch angle at the hover – i. e. Point 3 –
until the model again hovers at the stick centre point.
With the basic set-up completed, it should be possible to
start the motor in accordance with the operating instruc-
tions supplied with it, and adjust the idle setting using
the trim lever of the throttle / collective pitch stick. The
idle position which you set is indicated in the transmit-
ter’s basic screen display by a horizontal bar in the
display of the Ch 1 trim lever’s position. Refer to page 34
of this manual for a full explanation of the digital trims.
Around the mid-point of the collective pitch stick the
model should lift off the ground and hover at approxi-
mately the rotational speed you wish to use. If this is not
the case, correct the settings as follows:
1. The model does not lift off until the collective
pitch stick is above the centre point.
a) Rotational speed too low
Remedy: increase the
value for the throttle servo
parameter at Point 3 of the
stick travel in the
“Ch1
¼
throttle ” mixer, as shown in
the graph.
+100%
-100%
OUTPUT
2 3 4 5 1
Control travel
Hover
point
b) Rotational speed too high
Remedy: increase the
blade pitch angle for col-
lective pitch at Point 3 of
the stick travel in the
“Ch1
¼
collective pitch curve”
menu, as shown in the
graph.
+100%
-100%
OUTPUT
2 3 4 5 1
Control travel
Hover
point
2. The model lifts off below the centre point.
a) Rotational speed too high
Remedy: reduce the throt-
tle opening in the
“Ch1
¼
throttle” mixer at Point 3 of
the stick travel, as shown in
the graph.
+100%
-100%
OUTPUT
2 3 4 5 1
Control travel
Hover
point
b) Rotational speed too low
Remedy: reduce the blade
pitch angle for collective
pitch at Point 3 of the
stick travel in the
“Ch1
¼
collective pitch curve” , as
shown in the graph.
+100%
-100%
OUTPUT
2 3 4 5 1
Control travel
Hover
point
Important:
It is important to persevere with this adjustment pro-
cedure until the model hovers at the correct rotational
speed at the centre point of the throttle / collective pitch
stick. All the other model settings depend upon the cor-
rect setting of these parameters!
The standard set-up
The remainder of the standard adjustment procedure
is completed on the basis of the fundamental set-up
which you have just carried out, i. e. we now assume that
the model hovers in normal fl ight at the centre point of
the throttle / collective pitch stick, with the correct rotor
speed. This means that your model helicopter is capable
of hovering and also fl ying circuits in all phases whilst
maintaining a
constant system rotational speed.