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This item is discontinued. GREAT PLANES SPIRIT ARF 
SPECIFICATIONS Hits
Misses
There's a silent beauty in all things that soar. I've often watched with awe the hawks that lazily circle our flying field. Even the seagulls that thermal off the parking lot at the mall have a grace all their own. Naturally, thoughts of an RC model rising on that same prime updraft came to mind, but unfortunately, a sailplane just wasn't possible for me–at least, I thought so at the time. If you believe that there's no glider in your future, I'm glad I caught your attention! Great Planes offers two gliders that dispelled all of my preconceptions about owning a glider: I didn't have time to build one, and it wouldn't fit into the car or workshop when completed. Those reasons didn't matter when I had to decline an invitation for slope soaring and seafood on Cape Cod just because I didn't have a suitable plane. Timing is everything: Great Planes luckily had just released an ARF version of its Spirit Elite that has detatchable wings and a bolt-on tail. My first call was to Great Planes and the second to the gang in Massachusetts. By the time I had the Spirit ARF unpacked and on my workshop table, I was already chuckling as its design immediately dispelled my concern that I wouldn't have time enough to build it. It has about two dozen pieces, including the individual hardware components. It's as though Great Planes began with an assembled plane and told somebody to just break it down enough to fit it into the box. The glider has a two-piece polyhedral wing, and its main structure is of balsa and ply. Other than that the MonoKote needed some attention with a heat gun to remove a few wrinkles, the plane's overall workmanship is very good. The combination dihedral brace and wing joiner is a sandwich of two aluminum angle braces that I glued to a wooden spacer. Dry-fit the joiner into a main spar sleeve in the root of the wing panels and the wing assembly is complete! When the wing is rubber banded to the fuselage, the panels are compressed with sufficient pressure to prevent them from parting company. The vertical and horizontal stabilizers are both embedded with two threaded rods. The rods are pushed through predrilled mounting holes in the fuselage and are simply bolted into place. This arrangement ensures proper alignment and is also quick to break down for transportation. The control surfaces on the stabilizers have already been hinged and glued. After I had added the control horns, the radio gear and some final cosmetic details were all that remained to be done. The wooden servo rails slide into side grooves in the fuselage interior. I like this arrangement because it allows the approximate placement of radio gear and any balance fine-tuning is a matter of positioning the servos. I installed a pair of Hobbico CS-15 servos and the receiver for Tower's inexpensive 4-channel radio. After I had connected the pushrods, I painted the included pilot figure with Parma's FasKolor, glued on the canopy and attached the high-start launch. If you have a third channel on your radio, the Spirit ARF has spoilers already built into the wing panels! They're activated by a string that's attached to the spoiler's leading edge and run to an extra fuselage-mounted servo. This is handy when your approach is a bit hot and when you need to exit safely from a strong thermal. I really applaud this extra touch. If you decide to go with this option, cut the covering around the spoiler's sides and trailing edge. Start to finish, the whole assembly took only about two hours. My desire for trunk capacity hasn't yet overcome my yearning to keep my turbo- charged sportscar. Despite my shortage of space, the Spirit ARF is easy to transport. It takes only about three minutes to remove the rubber bands, disconnect the control horns and undo the four tail bolts. I've actually found it easier just to remove the vertical fin; the fuselage comfortably slips into my hatchback without being crowded by the high-start or the field box. The Spirit is a good value and a great change of pace. Whether you hand-launch, slope soar, high-start or have it towed up with another RC plane, it's an exciting new challenge. Now that nothing prevents you from owning a sailplane, what are you waiting for? FLIGHT PERFORMANCE Did I mention that I've never flown a glider, much less owned one. Before you scoff at my ability to accurately evaluate the Spirit ARF, remember that this is an entry-level 2-meter ship, and that makes the Spirit and me an ideal match. Takeoff and Landing I did a few trim hand-launches in the back of our local hobby shop. There's something almost disconcerting about flying a glider: your mind says, "Here's a big plane at low speed; it shouldn't be flying." The Spirit ARF, courtesy of its light wing loading, will do another two circuits of the field from the time you think it's ready to drop. For its size, the plane hand-launches easily, and the polyhedral wing is self-leveling. My heart rate elevated considerably with the ARF hooked on the high-start line. With a hefty batch of acceleration and wind noise, the Spirit ARF shot up as though it it had booster rockets attached. I had to hold in right rudder until its acceleration slowed, but all went well. Before I could do anything about it, it was soaring–no tuned pipe, no exhaust trail, no noise–it's exhilarating. Of course, I was obligated to yell "dead-stick" when I felt comfortable. Landing requires that you rethink your usual timetable. The downwind, base and final approach are done slower and farther away. I found it easiest to try to set up for a short "weedeater" landing; I was long every time! Low-speed Performance The inherent stability of a polyhedral-wing glider is amazing. If you have the radio, I recommend that you use the optional spoilers. The light wing loading is great until you run out of field. If you attempt to force a landing, the additional speed when the glider reaches ground effect usually leads to a wingtip pirouette. I never damaged it when this happened, but be aware that your entire landing approach to touchdown needs to be set up differently. High-speed Performance The only portion of flight I would consider "high speed" is during the bungee or winch launch. The wing has withstood these stresses without a hitch. Remember that converting altitude into airspeed is the only throttle available; this makes you less likely to waste "gas." Aerobatics Any type of stunt flying requires that you be well studied in lessons of power management. It's sort of like playing chess: you have to envision the outcome of your actions prior to executing a maneuver. With sufficient airspeed and altitude, the Spirit performs lazy loops and rolls. The Spirit ARF is a far cry from the more extra-caffeine planes that I've chosen over the years. It combines the excitement of the launch, the thrill of the thermal hunt and the challenge of precision landing all in one vehicle. I've become very fond of the techniques and artistry involved in unpowered flight. If you've done nothing but glow until now, I encourage you to catch the Spirit! Reprinted with permission.June, 2000 Model Airplane News Editor: Gerry Yarrish
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