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will need to be throttle conscious; that is, never apply full
throttle on straight and level flying or in dives to prevent
flutter.
3D Control Throws
ELEVATOR:
3-1/4" [83mm] Up
3-1/4" [83mm] Down
RUDDER:
6-1/2" [165mm] Right
6-1/2" [165mm] Left
AILERONS:
1-3/4" [45mm] Up
1-3/4" [45mm] Down
3D Servo Arms
Larger than stock servo arms are highly recommended
for getting the 3D throws for the Extra 300S ARF. Do not
move the pushrods in on the control horns to get the
increased throw, as doing that intensifies any play in the
system. Dubro Super Strength Arms sets (DUBM6670)
were used on the test models.
The large control throws require servos with great centering.
The digital servos are second to none in this department.
Digital servos such as the Futaba S9250 (FUTM0220)
should be used on all control surfaces of this airplane for
optimum performance. The test models were also flown
successfully in 3D mode with analog Futaba S9304
(FUTM0095) servos.
COMPUTER RADIOS
As you prepare to fly the Extra 300S ARF for the first
time, there are a few features on computer radios we'd
like to mention. There are many others, of course, but
these are commonly used features on most computer
radios. If you are using a non-computerized radio, this
information may still be of interest to you for future
installations.
ATV or Travel Volume: ATV is a wonderful feature of
computer radios which allows you to make minor
adjustments to how far a servo travels at its extremes.
For example, you install the throttle pushrod, and it's
almost perfect, except you have some binding at wide
open. Instead of struggling with the clevises to try to
keep full throttle but not have the binding, you can turn
down the ATV slightly until the binding is gone.
Servos
Why only adjust ATV slightly? Control linkages are
really just a lesson in leverage. The less distance the
servo is moving for a given throw at the surface, the less
leverage you have given the servo to do the job. Thus
the lower you set the ATV the less power you are
leaving for the servo to apply to the surface. Additionally,
a servo has only so many points within its range of
motion. By cutting its range in half, you've also
diminished the precision of the servo by 50%. Because
of both of these issues, we strongly recommend setting
the high rates as close as possible to 100% on the ATV.
Dual Rates: Setting dual rates helps make your model
easier to fly in a variety of situations. For example, an
expert pilot who wants to do torque rolls will need a
large amount of control throw. However, he does not
want that same huge volume of throw when he is trying
to do smooth loops or slow rolls. Low rates give your
model a soft feel, with aggressive responsiveness just a
flip of a switch away.
Exponential, the best of both rates: Exponential is a
feature which modelers tend to either love or hate. The
benefits of exponential are that they make the elevator,
for example, feel like it is on low rates when you are
moving the stick near center; however, when you get
farther from center the model gets progressively more
responsive. The reason this is helpful is that it allows
you to make soft, minor adjustments when small
corrections are needed, but still allows you sufficient
throw to make major changes at full stick. For example,
you can smoothly level the wings while flying along
straight and level without over-controlling, yet still have
enough aileron throw at full stick to complete a one-
second roll.
Idle Down and Throttle Kill: Idle down allows you to
have a switch set for a high idle, ideal for most
aerobatics where you have little or no risk of dead
sticking, as well as a lower idle setting for, say, landings,
taxiing, and minimum throttle maneuvers such as spins.
The throttle kill setting on most computer radios will idle
your engine down whatever percent you set it so that
your engine will shut off when the switch is thrown and
the throttle stick is in the idle position. This is an
excellent safety feature to shut off your engine in
emergency situations.
Have a ball! But always stay in control and fly in a safe
manner.
GOOD LUCK AND GREAT FLYING!
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