Table of Contents
Advertisement
Computer Radio Enhancements
A computer radio will allow you to do quite a bit of fine-tuning of
the feel of the Sukhoi, which will make aerobatics even easier.
Below are the programming enhancements I normally use to trim
out an aerobatic model.
• Rudder-to-Elevator and Rudder-to-Aileron Mixing
This mix is used to dial out unwanted pitch or roll caused
by the rudder. The Sukhoi has very little coupling, but
dialing it out will make knife-edge maneuvers easier. Use
a preprogrammed mix if your radio has this feature, or if
not, use a P-mix feature. Assign rudder as the master
channel and elevator as the slave. Set the mixing values
so when the rudder is deflected all the way in either direc-
tion on high rate, the elevator moves up 1/4". Fine-tune
this as part of your flight trimming process.
• Spoileron Mixing
This can be achieved by using either a preprogrammed
elevator to flap mix or a P-mix. Assign elevator as the
master channel and flap as the slave. Set the mix values
so that when full up, 3-D elevator is given, both ailerons
also go up 35-degrees. This mix helps stabilize the
model in some 3-D maneuvers, such as the Elevator
and Harrier.
• Throttle Curve
This is normally a preprogrammed function. It can also be
achieved in radios that do not have this premix but do have
curve type P-mixing by mixing throttle as the master and
slave channels. Then adjust the curve to get the desired
throttle servo response. This is particularly useful to get an
engine to "act" linear throughout the entire throttle stick
movement. I also use this at times to make the throttle
response less sensitive in the rpm ranges used for hovering
the model. This makes altitude control easier and smoother
when doing torque rolls.
Rates and Expos: When andWhere to
Use Them
I always use expo to soften the feel of the model. On high 3-D
rates, I use quite a bit. The goal on 3-D rates is to get the model
to feel the same around neutral as it does on low rates. I use
low-rate settings for all flying except for 3-D aerobatics. For
precision flying or general sport hot-dogging, the low rate
throws are perfect, even for snap rolls. The only exception is
rudder rates. I go to 3-D rate when doing stall turns and rolling
circles, since the more rudder the better for these. When doing
3-D aerobatics, I normally flip to 3-D rates just before the
maneuver. As soon as the maneuver is done, I flip back down to
low rate to avoid over-controlling the model.
Let's Get Down To It
When flying aerobatics with a larger model, you will find that it
will do everything just like a smaller model....only better and
easier. There are just a few exceptions to how things are done.
Throttle management is a must. You have to throttle back to idle
when the nose is pointed down.
Snap Rolls
Just like the need to be throttle managed like a full-scale airplane,
larger aerobatic airplanes need to be snapped like a full scale.
Let's back up to how we all learned to do a snap roll. If it's an
inside (positive) snap, we pull the sticks into the corner, i.e. full
up, full aileron, and full rudder in the same direction as aileron.
When we want to stop snapping, we release the controls. For
smaller models, this technique not only works but also is normally
the only way to get the model to snap. In a full-scale aerobatic
plane, as well as with large models, snaps are different,
particularly on the new breed of aerobatic birds like the Sukhoi,
which have large control surfaces.
Unloading Snaps
To start a snap roll, the same method as with a smaller model is
used. Pull full up, full rudder, and aileron in the same direction.
But soon as the sticks reach the corners, neutralize the elevator
while keeping the rudder and ailerons at full deflection. When
you do this correctly, the Sukhoi will not get "deep" into snaps.
This allows it to keep more airspeed as it exits the snap, so it
stops snapping where you what it to and flies out with more air
speed. You'll also find that it will be easier to exit a snap heading
the same direction you were when you entered the snap. It'll take
a little practice to get the hang of "flying" the snaps, but I'll bet
you'll see a big improvement in the quality of your flying.
37
Advertisement
Table of Contents
