I'm sure that most of you have already seen some of Adam Woodworth's Star Wars-inspired handiwork. Maybe it was the video of his RC Snowspeeder taking down an inflatable AT-AT. Or perhaps you caught Norm's interview with Adam about his drifting Landspeeder at Maker Faire. There are many other incredible examples as well.
I was able to tag up with Adam at the recent NEAT Fair in Downsville, NY. He brought several of the unique and wacky RC flying creations that he is known for (not all are Star Wars-related). The model that seemed to garner the most attention was his X-wing fighter.
Of course, the foam spaceship looks great. But Adam also logged several impressive demonstration flights that showcased his design's insane aerobatic chops.
From Space to Air
There are many examples of home-brew RC models that are based on various spaceships from the movies and television. Rarely are such projects easy. Let's face it, science fiction spaceships are seldom designed with Earth-based physics in mind. Significant concessions are frequently necessary for these movie-derived models to be airworthy. Even then, they are unlikely to fly as well as more-conventional aircraft designs.
With the X-wing, Adam set out to design a model that is true to the rebel ship's iconic profile, but also has impressive flight performance. I asked Adam how he accomplished this while adapting science fiction to real-life constraints. He replied, "X-wings are always a bit difficult to get in the air, because of the very long nose. This puts a lot of vertical and horizontal surface area in front of the center of gravity, which can make them unstable in yaw, and difficult to get crisp pitch control. On this build, I solved this by removing some material from the front half of the nose section, while maintaining the outline. This let me get the looks right, without the adverse handling qualities."
Adam's X-wing is built primarily of 9mm-thick Expanded Polypropylene (EPP) foam. EPP is very resilient and damage-resistant, but (because) it is also very flexible. Key areas of the X-wing's airframe are reinforced with thin plywood and/or carbon fiber rods.
The model is powered by two small brushless motors located between the angled wings. You would think that the motors and propellers would be a significant visual distraction. But they are hardly noticeable when the X-wing is in flight. And boy do those motors haul this ship around! Adam uses a single 4-cell LiPo battery. The resulting power output allows Adam to perform aggressive vertical takeoffs, whip out a slew of the aforementioned aerobatic stunts, and then end things with a vertical landing.
The control surfaces here are configured like a conventional flying wing model. The only difference is that the X-wing has twice as many wings! Each wing panel has a single elevon that controls both roll and pitch. A small 5-gram servo is dedicated to each elevon.
Yaw control is provided via differential thrust of the motors. For example, commanding the model to yaw to the right causes the right motor to slow down while the left motor speeds up. In Adam's setup, the yaw authority is so powerful that it is possible to make the X-wing pirouette on command from any flight attitude. Regular airplanes can't do that!
There are times when Adam prefers to tone things down a bit. So he installed a gyro unit to stabilize the yaw axis. The gyro is enabled when he wants smoother and less aggressive maneuvering. Adam turns the gyro off when he is ready to cut loose.
While the X-wing concept is fairly complex in any form, Adam made his model about as rudimentary as it could be. The simple profile wing and fuselage assure that the airframe is light and strong while still invoking the unmistakable image of an X-wing. A few simple cosmetic touches help to complete the illusion without sacrificing flight performance. The graphics were applied using laser-cut stencils and spray paint. And those laser cannons you see on the wingtips…they are actually plastic drinking straws!
If you're interested in building an aerobatic X-wing of your own, you are in luck. Adam reports that he is currently finalizing the design. When complete, he will post a build video on his YouTube channel that will also include a link to downloadable plans. So keep an eye out.
I am happy to report that Adam has more projects in the queue as well. He says that he is also planning a "REALLY big" X-wing. That will definitely be something to see. Adam also aspires to build RC versions of several G.I.-Joe vehicles. Based on Adam's history, I think we can expect some clever and innovative stuff to emerge from his workshop.
Under New Management
Thanks to a good bit of luck and Adam's generosity, I came home from the NEAT Fair with the X-wing airframe! I was really excited to get it set up with some of my gear and begin flying it. For the most part, I followed Adam's lead.
Adam's original 5-gram servos were still in place, so I added a 6-channel receiver and linked it to my Spektrum iX12 transmitter. For propulsion, I chose a pair of E-max 2204-2300 motors with 6x4.5 props. I decided to use a 3-cell 1300Ah LiPo battery for my first flights. Once I'm totally comfortable flying the X-wing, I'll switch to smaller props and a 4-cell battery for more power.
I did not see any reason to deviate from Adam's control configuration, so I stuck with elevons and differential thrust. It was all quite easy to set up. The only departure is that I omitted the gyro for yaw stabilization. As with any model that I am not yet familiar with, I wanted to keep things simple and remove any variables. I can always add a gyro later.
My first flight with the X-wing was much less dramatic than I predicted. I hand-launched the model with a light underhand toss and about half throttle. It flew away without so much as a hiccup. The X-wing profile not only looks really cool, but it also provides a lot of wing area. So this model is able to fly really slowly while still maintaining full control.
I was surprised by just how easy is it to fly the X-wing. It performs like so many of my other aerobatic park-flyers. You just tell it what to do and it responds without any unexpected side effects. All of the standard aerobatic moves such as loops and rolls are easy and look great. Maybe I'm overthinking things here, but I also think that my power system sounds a little like an X-wing streaking by on the big screen.
Most of my subsequent flights have begun with a vertical takeoff. Even my 3-cell setup has plenty of thrust for such shenanigans. The model sits on its tail with relative stability. All I have to do is jam the throttle forward and correct for any drift as the X-wing blasts into the sky.
The differential thrust yaw control is really fun to play with. My lower-power setup does not have quite the punch needed for on-demand pirouettes. It does, however, have plenty of authority for crazy flat spins and insane hammerheads. With a light touch on the yaw control, the X-wing also has super knife-edge performance…without a rudder!
My only challenge with the X-wing has been landing. I'm not nearly as talented a pilot as Adam and I haven't mastered how to lock the X-wing into a sustained hover. So vertical landings are not in my playbook at the moment.
The model has rather large vertical stabilizers positioned on the bottom side. This location helps to hide these non-scale features, but it also makes conventional landings difficult. The stabilizers at the rear are the first part of the model to contact the ground, causing the nose to smack down abruptly. I've caused a little damage this way. It is actually better to land inverted. While that sounds odd, the model lands so slowly, that the inverted approach and flare are no big deal. I think that most RC pilots who are comfortable with aerobatic park-flyers will have no trouble (and a ton of fun) with the X-wing.
My thanks to Adam Woodworth for sharing the details (and airframe!) of his X-wing design. This model goes to show that you do not always have to sacrifice flight performance when you create a flying rendition of your favorite sci-fi spaceship. Please share your own examples of RC spaceships on the comments section.
Terry is a freelance writer living in Buffalo, NY. Visit his website at TerryDunn.org and follow him on Twitter and Facebook. You can also hear Terry talk about RC hobbies as one of the hosts of the RC Roundtable podcast.