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Learning Advanced Aerobatics with
the Hangar 9 FuntanaS
 Several
folks have asked me to provide hints for pilots that
are interested in trying their hand at the latest
thrill-3D Aerobatics. This is a three-step
progressive flying guide for your Funtana. It's
designed for those who have moved up from trainers
or sport planes and want to try 3D with this
aircraft. The Funtana is an excellent airplane for
3D and you should find these techniques helpful for
building the most complicated freestyle sequences.
Step One - Airplane Setup and Configuration
To begin, one must start with a solid flying
platform before moving to the complex and exciting
3D maneuvers. I highly recommend that you utilize a
radio that has dual rates (low and high). The
airplane flies best on either of these two rates,
but not in-between. Flying in-between these two
rates, particularly on the elevator, will not be
enough for effective 3D, yet will be a handful to
try and fly conventionally. Using two rates (low
rate and 3D rate) allows you to safely and quickly
switch between the conventional rate and 3D.
Low Rate Setup
I recommend starting on low rate for Elevator
control throw, as shown in Figure 1. The rate that I
recommend is 5/8 inch up, and 3/4 inch down. This
differential provides the same loop radius for
inside and outside loops. Next is Aileron low rate
setup. Note the differential in the ailerons. By
having slightly more up (3/4 inch as shown in Figure
2) than down (5/8 inch as shown in Figure 3) it
allows more axial rolling.
High Rate (3D) Setup
Elevator high rates setup is shown in Figure 4.
Elevators are set on 3D rates at approximately 40
degrees up and down. Ailerons are set for 2 1/8 inch
up and 1 7/8 inch down. Again, the differential
helps during 3D.
Exponential
I suggest exponential in order to provide a softer
feel around neutral. For my setup, I use 15% expo on
all the surfaces on low rate to start. For 3D rates,
increase the expo in proportion to the percentage of
high rate. For example, 45% expo on high rate (that
has about 3 times more throw) will give a similar
feel as low rate around neutral, making it easier to
transition to and from 3D rates. My elevator dual
rates are 21% control throw on low rate with 15%
expo; 100% throw on high rate with 45% expo.
Flying Trim
Low rate should be used on the first flight, plus
takeoffs, landings and all conventional flying. I
suggest if you have "trim rate" adjustment on your
computer radio, set it to 1% for all the control
surfaces. This allows the fine trim resolution for a
perfect setup. After taking off, trim the Funtana
"hands-off" for 3/4 throttle straight-and-level. I
suggest trimming at 3/4 throttle because the plane
is designed for 3D speed. Reserve full throttle to
aid during aerobatic maneuvers.
Next, when you are comfortable with the
straight-and-level trim, pull a few loops. With the
throttle at half to 3/4 throttle, pull back all the
way on the elevator and add power over the top. Cut
the throttle to about 1/4 when nearing the bottom of
the loop. If you feel any tendency of the plane to
"roll off," reduce the low rate on the elevator
some, and add a couple of clicks of rudder. For
example, if the Funtana rolls off to the left as
it's coming around the last part of the loop, add
several "beeps" of right rudder. Figure 5 shows how
much right rudder trim I put in for nice stable
loops. I have about 1/16 inch of right rudder trim.
Also note that the elevator should be parallel with
the wing to provide smooth and precise loops. The
plane should now loop conventionally with no
tendency to snap, or roll off to one side.
Knife-Edge
Again, with throttle at trim-speed (3/4 throttle)
roll the plane into knife-edge and hold. It helps to
have someone next to you with a pad and paper. You
can verbally tell your helper "needs a little up
elevator with right rudder" for example, which you
can enter in the computer radio after you land. I
set up mine with 10 percent mix up elevator for
right rudder and 10 percent mix up elevator for left
rudder.
Conventional Aerobatics
Your Funtana is now set up for conventional
aerobatics. The plane should fly very stable in all
attitudes. It should roll and knife-edge well and
generally have the same feel as a standard (but
lightly wing loaded) sport plane. Fly it some to get
familiar with the plane in this configuration.
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3D Rate Elevator |
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Low Rate Elevator |
Step Two - Learning Basic 3D Aerobatic
Maneuvers
Now that the plane is set up, trimmed well and
you are familiar with its conventional aerobatic
flight characteristics-it's time for 3D. While
learning basic 3D maneuvers, I recommend takeoffs
and landings on low rate, while flying the 3D on
high rate, at a safe altitude, until you are very
familiar with the flight characteristics and
recovery.
The first basic 3D maneuver I suggest that you
start with is the 3D loop, or "Waterfall."
Basically, with the plane flying straight and level
(and a few mistakes high) switch to 3D rate, let the
plane slow down, and then simultaneously increase
the throttle and up elevator to complete a "3D"
loop. Normally, you reduce the throttle at the top
of the loop and the plane will come right around to
where you started. You can try this upright and
inverted. When inverted, you will find that the
torque and right thrust start to work against each
other during the outside loop. It's something that
is very similar in all 3D planes, whether TOC-size
or .40-size. More on this later…
The next maneuver is the 3D inverted spin. The
Funtana, like most 3D aircraft, prefers to spin to
the left. Enter the 3D spin as you do a conventional
spin, but as it begins to flat spin, add power and
adjust the elevator input to give you the desired
spin decent rate. So, by the numbers- enter from
inverted (high) stall and push the rudder right,
aileron left and down elevator (about half throw).
As the plane is spinning, increase elevator and
throttle settings to eventually flatten out the spin
until it is barely descending. To recover just ease
off the throttle some, neutralize the rudder and fly
out inverted. An interesting variant of the flat
spin entry is through a blender. Basically entering
high, upright, reduce the throttle and slow the
plane down. Next push the nose straight down and put
in left aileron. Finally push in the right rudder
then down elevator while increasing the throttle.
The resulting blender will transition into a flat
spin that you can continue working with and then fly
out as described above.
The final basic 3D maneuver is called the
Harrier/Elevator. Basically, enter this maneuver
medium altitude (several mistakes high) and slow the
plane down. Pop in the up elevator and the nose will
come up with the wings partially stalled- with the
plane settling in a vertical decent and the nose
level with the horizon (low throttle) demonstrates
an Elevator. A Harrier is a variant of the Elevator-
the plane begins to fly at the same altitude with
the nose pointed up about 30 degrees (medium
throttle). Here is the trick. The wings may begin to
rock- at which time you adjust the elevator, rudder
and aileron to reduce the oscillation. Wing rock is
a normal occurrence and takes place when the
horizontal stab partially blocks the vertical stab.
You can reduce the elevator input momentarily as the
wings cross level, which will damp out the wing
rock. There are two other techniques to use in order
to reduce the oscillation. First is through control
surface trim- turn out each aileron clevis to move
the ailerons "up" by about 1/8 inch. The second is
to adjust the 3D elevator rate to "tune" in the best
alpha angle, which reduces vertical stab turbulence.
For example, one may need slightly less than full up
elevator to settle in to nice harrier flight. From
there you steer with the rudder, and if needed a
little aileron.
Step Three- Advanced 3D Maneuvers
Finally, we are ready for the pinnacle of 3D
flight. Inverted Harriers, Torque Rolls, and Rolling
high alpha flight are the building blocks of all the
exotic freestyle sequences. I recommend that you
combine a practice regiment of flight simulator work
coupled with actual flight with the Funtana to
perfect these maneuvers.
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Inverted Harrier |
Inverted Harrier/Elevators. The inverted
version of the Harrier/Elevator maneuvers are very
stable and that is why many freestyle pilots prefer
them to upright harriers. The vertical stab is
pointed down and clear of any turbulence created by
the horizontal stab. Now, you'll notice that the
right thrust works as left thrust when you're
inverted. You may ask, "Why put right thrust in at
all?" Right thrust provides very stable upright
harrier flight as well as easier, more predictable
torque rolls. You also have that ultra-stable feel
during conventional (low rate) flight. How do you
get around the right thrust- inverted issue? You
have to add left rudder. This is particularly
important when you add throttle during inverted
harrier "cruising". Figure 6 shows what left rudder
input looks like when compensating for thrust/torque
during an inverted harrier.
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Low rate aileron
down |
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Low rate aileron up |
Torque Roll. The torque roll is just a
natural extension of upright and inverted harrier
flight. When pulling vertically out of a positive
Harrier for example, the plane will remain
stationary while you increase the throttle, then
begin to "torque" around to the left and begin
rolling "on the prop". Like all the 3D maneuvers, I
recommend starting at medium altitude until you
learn how to sustain (and recover from) torque
rolls. Recovery is normally no more difficult than a
half Waterfall back to level upright or inverted
flight. What's the secret to keeping things
"balanced" in a torque roll? Picture the airplane in
a conventional slow roll. As the plane starts to
roll, you have to add rudder, then down elevator,
then opposite rudder, then up elevator in order to
keep rolling axially. The same holds true for a
torque roll. If there is any wind, the airplane
(with respect to the ground) will try to
weather-vane into the wind and fall over. Just as
one puts control inputs to keep a conventional
slow-roll axial, the exact same inputs are used
during a torque roll to keep the plane vertical
(with respect to the ground). By the numbers- you
pull up vertically and reduce power until the plane
begins to torque roll. Lets take the case where you
enter downwind from the left (with the wind blowing
from the left). As the plane begins to rotate to the
left, first put left rudder in, then as the plane
rotates another 90 degrees, put in up elevator, then
right rudder, an finally as it comes around 360
degrees, put in down elevator. The whole time this
is occurring, the plane is drifting with the wind,
with the fuselage vertical with respect to the
ground. I attempted torque rolls unsuccessfully for
years until I learned this technique. After that,
the maneuver became easy.
The final step in learning advanced torque rolls
is refining the inputs to a point where you can tilt
the nose slightly into the wind without falling off.
This takes a lot of concentration but enables you to
torque roll with the plane in a stationary point,
without drifting in the wind.
Rolling Harriers. This is the final 3D
building block maneuver. I suggest increasing the
low rate ailerons at this time by about 10% to
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Right rudder trim |
15%, which puts them at about 40% throw. The
elevator has more than enough throw on low rate to
practice this maneuver, and there is enough rudder
to keep up with the plane. This maneuver is
basically executed similar to a regular roll, but
inputs are coordinated to keep the nose upward while
rolling.
This guide should give you the basic and advanced
maneuvers that can be combined, modified, and
tailored to build your exotic freestyle routine. For
additional references, check the Horizon website for
some additional details and descriptions on 3D
maneuvers. |
