Roll Tail rot. and Pitch axis Tail rot.
Tail rot.
Throttle
Roll
Throttle
Roll
Tail rot.
Nick
Throttle
Nick
Tail rot.
Normal
Increasing pitch is not the only change that requires a
corresponding torque compensation via the tail ro-
tor: major cyclic control movements also require this,
e. g. if the swashplate is tilted in any direction. Here,
too, the
mc-32
HoTT program lets you configure
settings for both types of tilt movement (roll and pitch-
axis) separately.
For advanced aerobatics in particular, which involve
very large control deflections in the pitch-axis con-
trols, e. g. the "Bo-turn" (vertical pull-up followed by
tipping over around the pitch-axis) and tight loops,
the uncompensated torque present in these flights
causes the model to turn to a greater or lesser de-
gree around the yaw axis. This spoils the appearance
of the maneuver.
These two mixers permit static torque compensation
to be activated by the swashplate tilting in any direc-
tion. The mixers work by always increasing tail rotor
thrust, starting from the centre point of the roll and
pitch-axis sticks, i. e. they always generate a tail ro-
tor deflection in the same direction regardless of the
direction of the command.
The mixer value can be varied within the range 0 to
+100 %.
198 Program description - Helicopter mixer
The mixer direction is determined automatically by
your definition of the direction of main rotor rotation
on the »Helicopter type« menu, page 108.
0%
0%
In the auto-rotation flight phase this mixer
0%
is automatically switched off.
0%
Gyro suppression
0%
SEL
Roll
Roll
Nick
Nick
Gyro suppression
Important: in normal situations, this
function should not be used if your
model is fitted with a modern gyro
system. In this context, ensure that you
comply with the instructions on adjusting
your gyro: if not, you risk making adjust-
ments that render your helicopter impossi-
ble to fly. This menu has nonetheless been re-
tained in order to cater to a full range of requirements
and flying habits.
With this option, the effect of the gyro sensor ("gyro")
can be varied according to the tail rotor stick position;
this assumes the use of a gyro system whose gyro
gain can be controlled from the transmitter via an
auxiliary channel. This channel will be channel 7 for
Graupner remote control systems. The gyro suppres-
sion function reduces gyro gain in a linear progres-
sion as the pilot increases the tail rotor deflection.
Without gyro suppression – i. e. when set to 0 % – the
gyro effect is constant, regardless of the stick posi-
tion.
Throttle
0%
Tail rot.
0%
Throttle
0%
Tail rot.
0%
0%
Normal
SEL
With a transmitter control assigned on the "Gyr7" line
on the »Control adjust« menu (page 126), e. g. one
of the proportional sliders mounted in the middle con-
sole; as applicable, also made flight-phase depend-
ent and/or with infinitely variable gyro effect between
minimum and maximum. In this case, gyro gain is
maximum at full deflection of the slider, and zero at
the opposite end-point.
Of course, the software lets you limit the gyro gain
range on both sides by altering the transmitter con-
trol travel.
Depending on the transmitter control's position, the
gyro gain at full travel on the tail rotor stick is:
"current control position
minus
gyro suppression value".
Accordingly, if the transmitter control is at the neutral
point, and gyro suppression is set to 100 %, the gyro
gain is reduced to zero as the tail rotor deflection in-
creases. For values between 100 % and the maximum
value of 199 %, the gyro can be fully suppressed – de-
pending on the transmitter control position – well
before full deflection of the tail rotor; see the diagram
on the next page.
For the Graupner/JR gyro NEJ-120 BB, No. 3277,
both the upper and the lower values are set via rotary
controls: control 1 sets the minimum gyro gain at the
bottom position of the slider; control 2 sets the maxi-
mum gain at the top end-point of the slider; the transi-
tion between these two values occurs roughly in the
middle of the slider travel.
In contrast, the PIEZO 900, PIEZO 2000 and PIE-
ZO 3000 gyro systems feature proportional, infinitely
variable adjustment of gyro gain; see below for typical
diagrams.