GRAUPNER MX-16S Programming Manual page 99

trol surfaces. when the brakes are extended.
A modern sweptback fl ying wing can be operated in a si-
milar fashion. These models also feature inboard and
outboard control surfaces: the former forward of the
Centre of Gravity, the latter aft of it. Defl ecting the in-
board control surface(s) down increases lift and pro-
duces an up-elevator effect. Defl ecting them up crea-
tes the opposite effect. In contrast, the outboard ailerons
have the reverse effect: a down-defl ection produces a
down-elevator effect, and vice versa. In this case there
are really no limits to what you can achieve with careful
thought and the sophisticated mixers of the mx-16s.
However, please note that you should be extremely ca-
reful when setting differential travel with such a confi gu-
ration, regardless of the type of servo arrangement you
are using. This is because differential travels tend to pro-
duce an asymmetrical elevator effect on a tailless mo-
del, rather than the desired adverse yaw reduction. For
this reason it is advisable to start with a differential set-
ting of 0%, at least for the fi rst few fl ights. When you are
familiar with the model and feel the need to experiment,
it may then be feasible under certain circumstances to
try differential settings deviating from zero.
For larger models it may be advisable to install wing-
lets fi tted with rudders, i.e. small vertical surfaces at the
wingtips. If these are actuated by two separate servos,
they can be controlled as described in the example on
page 96 dealing with "Servos running in parallel".
You may also want both rudders to defl ect outwards
when a braking system is operated using the C1 stick,
and this can be achieved as follows: if you have selec-
ted the "normal" tail type, set up two further mixers "c1
4" and "c1 control channel of the second rud-
der" with suitable travel settings. The offset should be
+100%, as the C1 stick is usually at the front end-point
when the airbrakes are retracted, and the winglet rud-
ders are required to defl ect outwards proportionally
Programming examples: Delta and fl ying wing 99