RC AEROBATICS 2013/07 There is a very thin line between “hobby” and “mental illness.”

The author’s new charge box is made from an XHeli EXI 250 aluminum carrying case.
There is a very thin line between
“hobby” and “mental illness.” —Dave Barry
by Mike Riggs
[email protected]
Since last year’s National
Society of Radio Controlled
Aerobatics (NSRCA) District 8
championships, I have sold one used
tent and bought three. My pursuit of
the ultimate “contest tent” continues.
Typical nighttime temperatures in
the inland Northwest are signifi cantly
lower than afternoon highs, making
for comfortable sleeping, even on the
hottest days of summer. Even expensive
tents generally cost less than a weekend
hotel stay.
Charge Boxes
Charge boxes are part of my hobby.
The bug killer box I presented in my
July 2012 column still works fi ne.
Why I needed another is truly a sign of
mental illness.
With many 24-plus-volt chargers
on the market, I purchased a 12/24-
volt, 47-amp Feather Power supply.
Feathermerchantrc.com power supplies
are reasonably priced, computer power
supplies converted for hobby use. Mine
works great.
In addition to standard features,
the new charge box sports a 12-volt
automotive power plug—aka cigarette
lighter. A car adapter will be used for
charging USB devices during the day.
This is a great feature for tent camping
at contests.
Let’s Fly Sportsman
With the 2013 contest season in full
swing and the RC Aerobatics Nats (July
21-25) and F3A World Championship
(August 15-25) around the corner, this
is a great time to give Pattern a try.
An expensive Pattern airplane is not
needed to fl y Sportsman Pattern. The
purpose of Sportsman is to introduce
pilots to Pattern.
Let’s take a look at the Sportsmen
sequence. Specifi cally, let’s look at how
the maneuvers are performed, and leave
“how to get good scores” for another
time. (I’m still learning how to get good
scores!)
Maneuvers are fl own in “the box.”
Imagine half of an ice cream cone at
60° laid on its side projecting up and
away from the pilot. All box entries and
exits must be declared to the judges.
Think of calling box entries and exits as
turning the judges “on” and “off.”
I’ll share a few universal fl ying
fundamentals:
• Have fun!
• Keep your wings level.
• Fly parallel to the runway.
Mastering these fundamentals
ensures good scores and rapid
matriculation through the class
schedules.
Takeoff
Start downwind of your position and
smoothly lift off directly in front of
yourself. Call “complete,” turning the
judges “off” 2 meters (61/2 feet) above
the ground.
Fly out and collect yourself, doing
whatever you need to do upwind,
staying upwind of the centerline, then
make one downwind trim pass. Get it
together again downwind before heading
upwind. Call “entering the box” at the
downwind box marker, and the judges
are “on.”
Straight Flight Out
Keeping the wings level, maintain
altitude and track parallel to the runway
100 meters (328 feet) out from the
runway centerline. If you can see the top
of your wings, they are not level.
Look for the bottom of the outside
wingtip. Not seeing the top of the wing
makes many inexperienced Pattern pilots
Visit www.ModelAviation.com
and click on Library to read the author’s
previous columns.
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Don Ramsey
spoke about
the basics of
Pattern, wind
corrections,
geometry of
maneuvers, and
expectations
during the GAMA
Pattern Clinic.
A pilot on
the flightline
concentrates
intensely during
the April 2013
Georgetown
Aero Modelers
Association
(GAMA) Pattern
Clinic in
Georgetown TX.
feel uncomfortable. It unnerved me.
Half-Reverse Cuban 8
Roughly two-thirds to three-quarters
of the way across the box, pull 45° up.
Count one-two-three and roll upside
down, maintaining the 45° upline
parallel to the runway.
On the three count, stay smooth with
wings level. With a constant radius, pull
to level. Breathe!
Straight Flight Back
This is the same as straight flight
out. Use rudder to control the crab
angle (parallel to the runway) in windy
conditions.
Stall Turn Without Rolls
Pull vertical slightly before the
downwind box end, correcting yaw
and roll in the vertical line. Pull back to
roughly one-quarter power and wait.
When the airplane stops moving
upward (stalls), toss the rudder
over while pivoting. Keep the wings
perpendicular to the flightline. Pull
power all the way back and gradually
release the rudder during the downline.
Pull smooth radius to level flight. Entry
and exit altitude should be the same.
Check level wings!
Two Inside Loops
On center, with wings level, pull nice
and round, keeping the wings level and
correcting the track with the rudder all
the way around. Superimpose the second
loop on the first. Call “exiting the box”
upwind. Breathe! Reposition the airplane
and call “entering the box” downwind.
Two-Point (2/2) Roll
A 2/2 roll means two of two points. A
2/4 roll means the first two points of a
four-point roll. Doing 2/4 from upright
would be pausing at knife-edge and
ending inverted. For Sportsman (2/2),
begin and end with wings level, centering
the inverted point in front of your
position.
Half Cuban 8
Smoothly pull 5/8 of a loop, ending
inverted on a 45° downline with a three
count: roll upright, three count, and pull
level.
Double Immelmann Without Rolls
A Double Immelmann without
rolls is a loop with top and bottom
straight segments. Imagine two circles
touching side-to-side. Draw a straight
line touching top-to-top and bottomto-
bottom and you have a Double
Immelmann without rolls.
Immelmann Turn
Pull a half loop at the upwind box
end. As the airplane becomes level
(inverted on top), roll upright. Check
the heading and that the wings are level.
45° Downline
Headed downwind roughly onethird
of the way across the box, push
downward to 45°. The runway center
bisects the downline. Pull to level and
call the box exit. Breathe! Get the
airplane lined up and call the box entry
flying upwind.
Vertical Upline (on Center)
Pull to a centered vertical line
pushing a constant (matching) radius
over the top to straight-and-level flight.
The top and bottom radius should
match.
Split S
A Split S is the opposite of the
Immelmann turn. Roll inverted, pulling
a half loop to level, checking that the
wings are level throughout.
One Horizontal Roll
Have a smooth, constant roll rate
with the inverted portion centered in
front of you. This is followed by another
Half-Reverse Cuban 8 (see second
maneuver).
Cobra Roll Without Rolls
Pull to a 45° upline, wings level,
then at center push over the top to
45° downline. Pull to level at the same
entry altitude. All radii—inside and
outside—should be equal. Call “exiting
the box” and breathe and relax. You are
done. Come around downwind for a
traditional landing approach.
Landing
On final approach, at 2 meters (61/2
feet) above the ground, call “landing,”
turning the judges “on.” In a nice,
gradual descent, track down the runway
centerline, keeping the wings level,
rotate and touch down directly in front
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of yourself. After rolling out, call “landing
complete” and turn the judges “off.”
At an actual contest, turn around
and thank the judges. It’s also a good
opportunity to ask for feedback about
your flight.
Wasn’t That Fun?
The next time you’re out horsing
around at the flying field, give the
Sportsman sequence a try. Fly it with
what you brought.
Email me if you would like an
electronic (printable) copy of the above
maneuver descriptions. I’d also like to
hear how you did. Maybe you could
email me some pictures.
Regarding pictures, I need Sportsman
of the Month pictures. On your next trip
to the field, take your camera and snap a
couple of photos.
I’d like to wish fair winds and safe
travels to those attending this year’s RC
Aerobatics Nats, and a special farewell
to Team USA F3A, which is headed to
South Africa. Go get ’em!
Flight complete.
SOURCES:
NSRCA
http://nsrca.us
2013 Sportsman Sequence
http://nsrca.us/images/stories/
currentsequences/2013_Sportsman_Sequence.
pdf
FeatherMerchantRC.com
[email protected].
www.feathermerchantrc.com
Team USA F3A
www.teamusaf3a.com
F3A World Championship
www.f3a2013.co.za
Georgetown Aero Modelers Association (GAMA)
www.gamarc.org
Xheli.com
(626) 968-9860
www.xheli.com/exi250alcaca.html
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