2
Assembly and Operations Manual VIMAR - EASY 3D FUN SPORT MODEL
Model airplanes, model engines, model engine fuel,
propellers and products such as the EASY 3D semi scale
sport model can be hazardous if improperly used. Be
cautious and follow all safety recommendations when
using your Model . Keep hands, tools, clothing and all
foreign objects well clear of engines when they are
operating. Take particular care to safeguard and protect
your eyes and fingers and the eyes and fingers of other
persons who may be nearby. Use only a good quality
propeller that has no cracks or flaws . Stay clear of the
propeller and stay clear of the plane of rotation defined by
the propeller.
The Manufacturer, Distributor, Retailer and/or other
suppliers of this product expressly disclaim any
warranties or representations, either expressed or
implied, including but not limited to implied warranties of
fitness for the purposes of achieving and sustaining
remotely controlled flight.
In no event will the Manufacturer, Distributor, Retailer
and/or other suppliers of this product have any obligation
arising from contract or tort, or for loss of revenue or
profit, or for indirect, special, incidental, consequential or
other damages arising from the use of this product.
In purchasing and/or using this product, the user accepts
all responsibility for its use and accepts all liability
associated with such use.
Liability Disclaimer
It is important that the following liability disclaimer be
READ BEFORE ASSEMBLING OR USING THIS PRODUCT.
A Remote Control Model Aircraft is not a toy. It is a
flying model that functions much like a full size airplane.
If you do not assemble and operate this product
properly you can cause injury to yourself and others
and damage property. DO NOT FLY this model if you
are not qualified.
You are solely responsible for the mechanical, aeronauti-
cal and electrical integrity of this model and it’s structure,
control surfaces, hinges, linkages, covering, engine,
radio, wiring, battery and all other components check all
components before and after each flight. Do not fly until
it’s right!
Proceeding with assembly and use of this product Indicates
Agreement With and Acceptance of the Liability Disclaimer .
CAUTION.
- This model is designed and constructed to be very
light for 3D maneuvers at low to moderate speed
and light to moderate stress.
- This model is not designed or manufactured for
high speed flight.
- Do NOT fly at high speeds under full throttle. The
model may break up suddenly if flown at high
speeds under full throttle.
- Do NOT fly on horizontal straight line at full
throttle as sudden brake up during flight is
possible.
- Full throttle should only be used for climbing
vertically, loops and rolls or in the case of an
emergency where power is needed.
- When descending, reduce your power setting
immediately. Do not allow the model to accelerate
to high speeds in a dive.
- Do NOT overpower this model. Normal operation
requires only half throttle.
- Careful use of the throttle is required to prevent
breakup of this model in flight. Do not overpower
or overstress this model.
- This model is for intermediate and advanced RC
model pilots. It is NOT suitable for beginners.
- This model has been flight tested with snap-rolls
and other aerobatic maneuvers. Do NOT over-
stress the airframe with repetitive, violent, extreme
or high speed maneuvers.
- Inspect this model thoroughly before and after
each and every flight. Watch for stress cracks,
loose joints or other abnormalities. Repair any
defects before flying.
- Be alert for unexpected and/or irregular responses
during flight. Slow down, reduce stress on the
airframe and land immediately if flight response is
compromised in any way.
- Check all linkages, hinges, components and
control surfaces before and after each flight.
Although this model may be partially
pre-assembled you are solely responsible for the
integrity and flight worthiness.
- Do NOT overpower this model. This model is
designed for 2 stroke .46-.52 sized glow fueled
engines OR similar power four stroke engines or
similar output electric motors. Overpowering this
model will result in airframe failure.
W
W
A
A
R
R
N
N
I
I
N
N
G
G
Assembly and Operations Manual VIMAR - EASY 3D FUN SPORT MODEL
15
THRUST TO WEIGHT RATIO
The engine must be able to lift the plane vertically, which is a com-
bination of propeller selection and fuel. You need a power to weight
ratio of at least 1.5 to 1. We do not want to hover at full throttle, we
want to ideally hover at half throttle. We need the reserve power
because we are vectoring propwash off the ailerons to generate the
high degree of roll, and this robs lift and requires the increase in
throttle. A high speed torque roll requires the most power, in the
order of 2:1 just to maintain altitude! Suffice to say that this is a very
advanced hovering maneuver! You need a very reliable engine.
Hovering is great until the noise stops!
Do not use an engine that has a history of running hot or lean. On
the average .40 powered ship, look to configure your plane with a
“heli-like” setup. By this I mean, choose a prop with the biggest
diameter and lowest pitch which will function with the landing gear
and flight envelope of your plane. I have found that the 11x4 prop is
outstanding for hovering with most .40 powered planes. The engines
swing it easily, (you do not want to over heat), and the four inch pitch
generates gobs of thrust at lower flight speeds.
Fuel selection is important. Since we are trying to hover at half of
our available throttle, consider using a higher nitro fuel. The more
nitro, the cooler the engine runs. This is because the nitro brings
more oxygen into the engine and this is where the power boost and
substantial cooling takes place. High Nitro causes harm when you
are at high throttle settings and at rpm’s that overcome the cooling
effects of the nitromethane.
FLYING
You might think that heli experience is helpful, but there are conflicts
with that logic. When you stand your plane on its tail, the yaw axis is
controlled by your ailerons, not the rudder. The rudder, (left stick) con-
trols the roll axis! Heli pilots need to teach their fingers some new
tricks or they will find themselves in trouble!
The throttle, of course, is no longer fast and slow, it is now for ris-
ing and decending. There is no “chopping the throttle” when you get
in trouble here! Try that, and you will find that tail first impacts break
things on your plane that you have never seen broken before.
Start with transitioning to hover by practicing holding higher and
higher angles of attack and learning how much throttle to add to
compensate for the lost lift, no longer generated by the wings. As
you pass through the 45 degree angle point, you will find that your
speed drops almost to zero very quickly. You’ll need the most right
rudder at around 45 degrees. As you approach vertical, you’ll find
that most planes still want some right rudder, even when hanging
vertically. I believe this has more to do with countering torque than
any other factor, whereas the rudder compensation at the 45 degree
angle is almost all due to “P” factor. (more on “P” factor in a future
column).
If your plane needs too much throttle to make the transition and
you constantly end up gaining altitude in order to get the plane into
the vertical position, this suggests that you are nose heavy, or lack-
ing in elevator authority needed to swing the tail under the plane.
Running the CG aft of the recommended area is tricky business, but
it can make all the difference in a stable transition. Practice is the
key, but keep a careful eye on the fuel tank and the air/fuel mixture
feeding the engine. You can’t afford for the engine to go lean now!
Flying into and out of a stable hover requires power. If your plane
does not have a low wing loading, you may find that it belly flops
when you go to exit the hover. This is due to the rapid transition back
to “wing-borne” flight—this transition may leave you at such a low
airspeed that the wings won’t to hold the plane up. Expect that the
plane will need a boost of power to get it back to “horizontal” flying
speed! Give it this boost just as it starts to pitch over.
Like your first landings, a quality performance takes practice. Start
a bit on the high side to see how your plane behaves and stick with
it. Soon you will be hanging in space. One thing that hovering teach-
es you is to be a master of your left hand!
Good Luck-Dave Baron
Editor’s note: we asked noted TOC pilot Jason Shulman whether
hovering smaller models was different from hovering large TOC-size
aircraft, and also for his views on the basics of hovering, from setup
to pilot focus.
Jason Shulman: I recently had a great opportunity to judge this first
hand at the Joe-Nall giant scale fly-in. I was hovering my Exhila (one
pound all up weight) on both calm days and windy days. I was also
hovering a few 30% and larger planes during these same conditions.
The first thing I noticed is that in calm conditions, there was really no
difference. Everything was smooth and predictable. But the windy
conditions posed a few differences. The small plane was very sen-
sitive to the wind in hover. Not so much in terms of drift, because
even the large planes drifted. But the slight variances in the wind
would throw the Exhila around, while not really bothering the larger
planes.
I also noticed that the smaller plane would hover, at times, at a 45-
degree angle (leaning into the wind), whereas the larger planes
would hover at about a 15-20 degree angle in the same winds. This
made the smaller plane much harder to hover. Once you start push-
ing to a 45-degree angle, you are entering a kind of forward flight
with the associated flight characteristics. So not only are you trying
to balance the plane on its tail, but you are also trying to keep it from
flying forward.
Although both large and small hovering planes will drift in the wind,
one of the most apparent differences is the speed of the drift. When
I hovered the large planes, drift was relatively slow, and smooth
looking. The Exhila was a different story: it scooted across the field
like it was flying level at 1/3 power.
SETUP
When setting up a plane to hover, regardless of size, you follow the
same principles.
Center of Gravity (CG).
The CG should be slightly aft so that
the plane is slightly tail heavy as compared to the normal, or recom-
mended, flying CG position. The larger the plane, the larger the CG
range is. On my Exhila, moving the CG back 1 inch can cause it to
be very unstable and almost impossible to fly. On my TOC planes, I
can move the CG back 3-4 inches and they will still be controllable.
Generally, I move the CG back 1/2 in. at a time on the larger planes,
and 1/8 in. on the smaller planes. There is also a point where you
can have the CG back too far and hovering becomes harder to per-
form.
Control Throws.
I have found it best to fly with dual-rates. I set
a low rate, which is good for general or pattern flying and then max
out all of the surfaces for a high rate of roughly 45-degrees of deflec-
tion for hovering. I fly thumbs, so I like a little bite of Exponential on
my low rates and a much higher setting on my high rates. My set-up
on Expo is for a “soft-center” feel on both rates. Pilots that fly with
HOVERING TIPS FROM
THE MASTER
by Jason Shulman
The closer you are to the
ground, the faster you
detect, and can react to,
which way you are drifting.
Note that the tail feathers
and the servo gears that
push them are a bit fragile
and not used to contacting
the ground before more
rugged parts of the plane
do!
