Model menu
Rudder -> elevator
Snap roll
F X - 4 0
18.19 SNAP ROLL FUNCTION
The snap roll function enables you to define transmitter control
positions which cause the aeroplane to carry out a particular
flight manoeuvre. The model then flies this manoeuvre when
you operate a switch. The servo settings cannot be overridden
while the switch is in the ‘ON’ position.
For each flight manoeuvre it is possible to define four settings
(right / up; right / down; left / up; left / down) for each of the
three primary control surfaces (aileron, elevator and rudder). A
mode (Central or Separate) can also be defined, which deter-
mines whether a Master switch or any other switch is to be
used to initiate and conclude the manoeuvre. If you select
Central mode, the trigger switch (Central SW) must also be
defined. It is important to assign a safety switch (Safe SW).
The Master switch is then only active when the ‘safety switch’
is in the ‘ON’ position. The purpose of this precaution is to
ensure that you never trigger the snap roll manoeuvre acciden-
tally.
It is also possible to determine whether the settings are to
apply to all flight modes (Glob) or only to the currently activa-
ted flight mode (Sepa); the familiar procedure is required for
this. A trigger switch can be defined for all four directions of
movement individually. The servo travel can be entered as a
percentage value for all three control surfaces (aileron, elevator
and rudder), separately for each direction of movement.
With the ‘Power model’ type already set, mark the ‘Snap roll’
function in the Model menu. The screen display now looks like
this:
The first step is to define the mode in the first line. If you wish
to use ‘Central’ mode, you must then assign the ‘Central SW’
for activating the function. All the usual transmitter controls
and switches are available for this in the switch select menu.
You should then use the same method to define a safety
switch (Safe SW). Setting global or separate mode concludes
the first part of the programming procedure.
Next you have to define the switches for the individual direc-
tions of movement; the procedure has been described several
times, and must be familiar by now. A separate frame is provi-
ded for programming the control surface travels (i.e. the servo
travels) as percentage values. Mark the appropriate field in the
usual way, and enter the value using the arrow buttons. The
adjustment range is -150% to +150%. The default setting is
100%; pressing the ‘Reset’ button restores this setting.
Please be particularly careful when programming this function,
and take care not to enter any settings which could lead to
uncontrollable flight situations. The following screen shot
shows a typical example of programming for a simple snap roll
manoeuvre.
81
18.18 RUDDER -> ELEVATOR MIXER
(flying wing models only)
Many flying wings exhibit a tendency to dive slightly when a
rudder command is given, and the purpose of this mixer is to
cause the elevator to deflect up when a rudder command is
given. This function may also be of interest to pilots who enjoy
extreme 3-D aerobatics.
The mixer rate can be set up accurately using a curve. The
function can be activated by a switch which you can select,
and can be connected to other mixers by setting up a link. As
with many functions, it is also possible to determine whether
the settings are to apply to all flight modes (Glob) or only to the
currently activated flight mode (Sepa). An auxiliary transmitter
control can be assigned for fine-tuning the settings.
With the model type ‘Power model’ already defined, mark the
‘Rudder -> elevator’ option in the Model menu. The screen
display now looks like this:
This function is programmed in exactly the same way as the
Rudder -> aileron mixer. For this reason the description here
only covers the essentials; for full details you can refer to Sec-
tion 18.7 on page 70.
The first step, as with all other mixers, is to activate it in the
‘INA’ field in the first line, after which you can define a switch
and its direction of operation in the usual way. You can now set
the ‘Glob’ or ‘Sepa’ mode in the customary manner.
If you wish to link this mixer to another mixer, the appropriate
settings should be entered in the ‘Link’ line. You must first acti-
vate this option, then define the mixer to which a link is to be
created. You can set your preferred display mode in the ‘Dis-
play’ field: (All modes), (Separate) or (Fine).
A separate frame is provided, in which you can enter the set-
tings for the optional fine-tuning facility using the familiar
method.
As previously described, it is possible to set up and program a
mixer curve in the right part of this display level. The mixer
curve you set up at this point defines the effect of the mixer;
i.e. it determines the amount by which the elevator deflects
when a rudder command is given.
The curve values are adjusted exactly as described for pro-
gramming the Dual Rate curves. Please refer to Section 17.2
on page 58.
