Author: Mike Riggs
Edition: Model Aviation - 2013/07
Page Numbers: 109,110,111
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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 significantly 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 fine. 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 fly Sportsman Pattern. The purpose of Sportsman is to introduce pilots to Pattern.

Let’s take a look at the Sportsman sequence. Specifically, 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 flown 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 flying 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 (6½ 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 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 (keep the fuselage 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 a 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 bottom-to-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 one-third 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 a 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 (6½ 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 of your position. 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

Transcribed from original scans by AI. Minor OCR errors may remain.