User Manual

Balancing: The recommended starting balance (CG) point of the 47” Extra is 3.5 inches behind the
leading edge of the wing measured at the root of the wing, where the wing meets the fuselage.This is a
conservative CG location, excellent for sport flying or precision flight. For 3D flying, you may wish to
move your CG back. If you do so, move it in small increments, a small change can have a large
effect.
An easy way to verify your CG settings during tuning is to do the “roll inverted” test. Trim your plane
for perfect upright hands-off flight. Then, with sufficient altitude, at ¾ throttle, roll inverted and
release the controls. Your airplane should very gently descend. If instead, it climbs, it is far too
tail-heavy. If it dives sharply, it is too nose heavy.
Scott’s Tip:
Control Throws and Exponential
Setting appropriate control throws is a critical step in matching your model to your
flying style. Personally, I use two different flight “modes”– precision and 3D. Depending
upon your radio, you may be able to combine all three dual rate functions onto a single
switch, which is the technique I use. Regardless, be sure to use a common assignment
scheme to prevent being in the wrong rate at the wrong time. I prefer my switches to be
higher for high rates and lower for low rates, but virtually any combination will work –
just be comfortable with your setup.
Low/Precision Rates (in degrees and inches) and Corresponding Exponential
Aileron 15 degrees .75” 30% Expo
Elevator 13 degrees 1.25” 30% Expo
Rudder 45 degrees 3.5” 75% Expo
High/3D Rates (in degrees and inches) and Corresponding Exponential
Aileron 28 degrees 1.25” 75% Expo
Elevator 45 degrees 3” 85% Expo
Rudder 45 degrees 3.5” 75% Expo
The above throw measurements were taken at the aft edge of the ailerons and
elevator, and from the bottom aft edge of the rudder. Keep in mind that even the low
throws mentioned here are relatively aggressive, so be sure to also program the matching
exponential listed to help soften the model’s feel around center stick.
One of the things you may notice is that my low rates are dramatically lower than
you might expect. I find that I have such great control authority that I need to minimize the
elevator in particular or the snap rolls will be far too deep into the stall for clean
recoveries. You should also note that even the high aileron rates are also relatively sedate
compared to the extreme 45 degree throws common to 3D models. I set my 3D rate aileron
throw for a comfortable roll rate during the slowest rolling maneuver I fly – the rolling
harrier. I prefer to hold full aileron throw during the rolling harrier, so excess throw results
in excess roller rate, which is detrimental to not only the maneuver’s appearance, but also
the maneuver’s timing.