We have reached a peak in our pursuit of the perfect combat plane.
The perfect candidate can float slowly in the air, then zip forward, up or down for a lightning strike or getaway. It can loop in a heartbeat and speed straight to a target. It laughs at wind and spins in a tight victory roll after bashing an opponent.
The Great Meadow is our laboratory and we’ve had altogether too much fun conducting this research.
Speed Doesn’t Kill. One of our earliest combat discoveries was that speed is not your friend. A fast plane overshoots its target.
You want to confine your flying to a small volume of air in front of you. As you reduce the volume of the combat arena, you increase the chance of contact. For more excitement, increase the number of combatants in that small arena.
So you want to fly slow. You want a light plane because
- Light planes fly slow
- Light planes crash light
- Light planes fly long
We Want It All. In addition, our dream combat vehicle is
- Easy to Build
- Easy to Repair
The winner? A hacked Wild Wing, not the first hack or the second, but maybe the third or fourth.
The Wild Wing is a $20 35-inch wing kit sold by Hobby People. [Update: as of November, 2008, Hobby People is out of Wild Wings. As of March, 2009, Mike Bowns has developed a replacement that flies even better.]
Butch’s Boomer. We were pointed to the Wild Wing by the Boomer, an agile slow-flyer which has proven excellent for combat. It’s based on a cut-down Wild Wing, with numerous added parts, including a boom, nose and elevator.
The Boomer has inspired regular combat sessions in Livermore and is the focus of a lively discussion on RC Groups led by Butch, who conceived and designed the twin-boom wing with aelerons and elevator.
Dave North pioneered our Wild Wing variations. He started by mounting the motor in the middle, then moved it aft and experimented with horizontal stabilizers, various size elevons and different vertical stabilizers. He cut the wing down, tinkered with various motor and prop combinations and one day walked out of his lab with a perfect little warrior.
Close Combat. Since that fine day, several of us have copied his ideas. The result is intense close-quarters combat with lots of contact but very little damage.
If you’d like to join the fun, this is what you need:
- Wild Wing kit
- 9 or 10 amp speed control
- 2800 kV outrunner motor turning a GWS 5×4.3 propeller
- 2S 730mah battery, or smaller
- 2 micro servos
- 9mm EPP sheet
- 6mm Depron sheet
- Control horns & control rods
- Goop and/or Canopy Glue
- Hinging Tape (Blenderm or 3M)
Rare Bird. First, a few words about the motor. Unfortunately, efficient 2800 Kv outrunners are nonexistent.
Dave will make you a motor in exchange for two hexTronik 16-gram Brushless Outrunners from Hobby City. If you want to buy a motor online, here are Dave’s recommendations: “Only two that I know of might be suitable, and both are inferior. The Little Screamer Park Jet is 2800 Kv and will more or less turn a 5043 about right. The 24-gram Hextronic 3000Kv is okay for 5030 props and marginal for 5043 (might stress the ESC depending). Neither is quite right. Efficiency is unsatisfactory in both motors. Other than those two ‘efforts,’ it’s a completely unaddressed market.”
Flying time with a 730mah 2S LiPo and an efficient motor is about 12 minutes, though I generally limit my flights to 10 minutes so I don’t bash the battery. (And I fly some batteries that are 2+ years old.)
Bigger Prop. Alternatively, you can use a different motor turning a larger prop. If so, you’ll need to adjust the following measurements, which assume a 5-inch propeller.
First, slice the wood strips off the trailing edge of the Wild Wing. You don’t need them.
Mark the center line of the Wild Wing.
Cut the wing on both sides 2.125 inches from the center line, leaving approximately 6 inches of foam between the two vertical stab slots.
Kitchen Knife. To cut the foam, mark the lines with a pencil, then score the cut with a couple of passes using a fresh sharp razor and a straight edge. To finish the cut and keep it straight, sneak into the kitchen and insert a carving knife or chef’s knife into the razor cut, then slice. It’s surprisingly easy.
Mate the two halves and check the fit. Sand as necessary to achieve a smooth join.
Battery Compartment. At this point, Dave carves out a neat pocket for the battery. I didn’t think ahead, so later I used a soldering gun with some heavy gauge copper wire to burn a slightly messier pocket for the battery.
Glue the wing halves together using Goop, Uhu Creativ or Canopy Glue, set them on wax paper on a flat surface with weights and let dry overnight.
The rest is straightforward. Refer to the photos and captions and feel free to ask for details if you need additional information.
Inset the motor mount about 0.5 inch so you don’t have to add nose weight. Update: Inset the motor mount at least 1 inch to avoid a tail-heavy plane. If it turns out nose-heavy, you can add spacers to the firewall to extend the motor rearward.
Replace the stock elevons with larger elevons cut from 6mm Depron (mine are 2.5 x 12 inches, a rectangle with one short side angled in a few degrees to clear the elevon, plus rounded corners) and replace the vertical stabilizers with lighter ones cut from 6mm EPP. Here’s a printable PDF pattern for the vertical stabilizer. Don’t try to glue the vertical stabs into the slots: glue them on top of the slots.
We hinged the elevons using Blenderm, a wonderfully sticky tape which seems immune to UV radiation. Use Blenderm on both sides of the elevons. You’ll find Blenderm at some local R/C dealers, or look for it online. Set the elevons for big throws.
Update: Initially, I installed very lightweight servos, but after stripping gears multiple times I’ve replaced them with heavier models. I seal the servos with clear tape, then Goop them into the servo cutouts.
Dash of Color. I painted the elevons and vertical stabs with orange acrylic paint using an air brush. A bit of color will help you identify your warship in the heat of combat.
Protect the nose and the leading edge with filament tape — the front takes a lot of abuse in combat.
Aim for AUW (including battery, of course) of less than 7 ounces. My wing is 6.5 ounces. Dave’s is a bit lighter.
Gaining Momentum. So far, Dave, Frank D and I are flying these small WWs. Mike Nadler’s working on his and I expect to see many more quite soon.
They mix perfectly with other small wings — Mini SpeedWings, HyperFleas and, of course, Boomers — but they’re the most agile combatants in the air: Monkeys vs. Cats.
If you’re building a plane for combat, keep it light and don’t add hard reinforcements such as carbon fiber rods on the leading edge of the wing. These add weight and create an unnecessary hazard for your opponents. All you need is a bit of tape on the leading edge.
If you want to get a suitable Wild Wing motor from Dave North, send me an email and I’ll put you in touch with him.
Here’s an article by Mike Bowns on how to build a Wild Wing, with lots of pictures.