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GREAT PLANES SPIRIT ELITE 
Aircraft Type Sailplane, 2 Meter Class Basic Materials Used In Construction RCM PROTOTYPE SUMMARY  Great Planes originally introduced the Spirit as an entry-level sailplane. Trouble is the designer then went out and promptly won the Nationals with it! Fact was that while it was rugged, easy building, and had the docile handling characteristics of a glider trainer, it also offered great thermaling capability. Over time, Great Planes evolved the original Spirit to include the electric powered "Spectra" and the enlarged "Spirit 100" to help newcomers to the sport of soaring. While still a great bird, the original 2M Spirit was ready for an updating, and that's where the new Spirit Elite comes in. The Elite takes everything about the original Spirit and makes it thinner, slimmer, and faster. The original's S3010 wing section is replaced with a state of the art transitional SA7035-7036. The fuselage is a little lower and narrower; the tail feathers a bit more rakish. While it can still be built with simple Rudder/Elevator controls, the Spirit Elite is really intended to be a modern full-house bird with flaps and ailerons. Think of the Spirit Elite as a Spirit raised on health food. There were nine bundles and packages of material plus a few odd pieces of material lying snugly in the brightly decorated 2.5" x 6.5" x 46" box. The 36" x 50" printed plan sheet was rolled. The 32-page instruction book is profusely illustrated and contains several other useful features. For example, there is a complete set of die-cut patterns that can be used to identify parts, a list of material needed to complete the kit, a tip sheet on hi-start launching, both thermal and slope soaring, and a flight log. A personal favorite feature was that the "centerfold" of the manual is a reduced size plan sheet. Prior to building I went through and read the instructions and crosschecked the installation diagrams with the reduced size plan and the die-cut sheet all from an easy chair. Certainly it contributed to the quick building of the review kit.  Construction: The builder will need the usual assortment of modeling tools, the structure is "CA-friendly" and Great Planes thin and medium CA's were used for most construction. I also used Great Planes 6-Minute Epoxy and wood glue. As a veteran of several Great Planes kits it came as no surprise to me that the die-cutting was absolutely flawless. Part of their secret is that they do not die-cut anything thicker than 1/8", so the cuts are always clean. Construction begins with the tail. Except for a few die-cut pieces in the middle of the stab and elevator, the tail is constructed of various 3/16" thick strips cut to fit. Nothing terribly mysterious here. The key thing is to make sure you sand out the finished structure, especially the glue spots where all the joints come together. Make sure to get nice thin trailing edges. I've found this job is easier when I first hinge the surfaces together. It makes it easier to hold everything still while I sand it out. I made one small change the design calls for a MonoKote hinge on the elevator; I used small CA type hinges, then MonoKoted over them to seal the hinge gap.  The fuselage sides are two-piece with balsa doublers and a plywood tripler in the wing saddle area. Bulkheads are tabbed and grooved to interlock with the fuselage sides. The fuselage bottom from the nose block to roughly the back of the wing saddle is plywood, then sheeted with balsa toward the tail. Top and bottom sheeting is also tabbed and slotted with the fuselage sides and bulkheads. Great Planes supplies a set of its plastic pushrods and the holes for the sheaths are pre-cut in the fuselage sides and the bulkheads. Unlike the earlier kit, the Spirit Elite is designed for a bolt-on wing as standard, and a nice robust hold-down block is provided. I pre-weighted the nose block with 1.5 oz. of shot, and that was nearly too much. I used my router table to get a nice uniform 3/8" radius on the fuselage corners, then finished-sanded it. Unlike earlier Spirits, the canopy is opaque white styrene. It is again fitted to a balsa and plywood frame and held down in front with a dowel and in back with a rubber band. First step in building the wing is to construct the center wing joiner bar. This consists of a 1/16" thick aluminum core with two layers of 1/16" plywood on each facing. Finally, the 5-layer lamination is capped top and bottom with another piece of 1/16" plywood. I did the laminations using Great Planes 6-Minute Epoxy then trued up the top and bottom surfaces and capped them using epoxy. Finally, the joiner must be sanded smooth and de-burred on the outside. The joiner is used early in the construction sequence to set up the spar boxes. The wing construction is a traditional D-box with a couple little twists. Before getting too deep into the wing construction, the builder must decide between a modern aileron/flap equipped wing or a polyhedral wing with the ailerons glued stationary. The wing is built in four panels, then the outer panels are joined to the inner panels using either a straight or polyhedral plywood joiner. The review kit was built "full house" with ailerons and flaps. The airfoil is not flat bottomed but Great Planes has engineered some nice features into the Spirit Elite to make it easy to build on a flat board. The wing ribs are equipped with tabs on both the top and bottom and is designed to be built starting upside down on one set of tabs, then flipped over. A second set of tabs aligns the wing and sets the washout while the wing is sheeted on the top. This is a slick way to create a modern bird using built-up structures. I also liked the spar web which is die-cut and which is used to space the wing ribs. The wood grain runs spanwise which contributes to its bending strength. This structure should tolerate aggressive launching but I would not say that it is winch-proof. Flaps and ailerons are made from tapered solid balsa. The ailerons are top-hinged and have to be beveled a little on the bottom in order to allow full throw. The flaps are bottom hinged; depending on the hinge gap you can achieve, you might have to bevel these very slightly in order to allow for reflexing the flaps. Again, I opted to permanently hinge these surfaces to the wing (using CA hinges) then MonoKoted over the gap. The biggest things to watch out for here is to sand the flaps and ailerons to fit the trailing edge of the wing, and to sand the trailing edges of the flaps and ailerons as thin as you dare. Cut and shape the wingtips from solid blocks aligned with the tip rib. Note: Because the wing is built with washout, when the ailerons are aligned in neutral with the flaps, they hang below the tip at the trailing edge. Conversely, when they are aligned with the tip, they show an "up" setting versus the flap. The only way I know to correct this would be to carve ailerons with "twist" in them to make up for the presence of the wash-out. I anticipate some experimentation with different settings in flight. Covering: For my sailplanes I am really fond of using bright colors on the top and dark colors on the bottom for maximum visibility. Thus, the Spirit was covered with MonoKote Neon Yellow on top with Black leading edges and the entire underside is Black. A narrow Neon Orange stripe sets off the color break on top. The pressure-sensitive decals that came with the kit were then applied all over. I held off final assembly of the components until all were covered, this simplifies the task. The canopy was left in its plain white styrene. It looks a little stark, so I might paint it some time in the future. Radio: As a full-house bird it needed a full-house computer radio. Out came the trusty old Ace MicroPro 8000 that I use with my other sailplanes. There was ample space for the standard sized receiver and the 600 mAh battery pack. One subtle change I had made in the radio installation I prefer to have the servos located ahead of the receiver, so I modified the kit's standard radio installation to suit by moving the servo rails forward. The kit plans show Futaba S3101 micro servos in all locations. I opted for somewhat larger Hobbico CS-35's in the fuselage and for the flaps, and Hobbico CS-12's for the ailerons. The CS-35's are a mid-size servo with tremendous torque, but they are too thick for the aileron location. In fact, they were a tight squeeze for the flaps too. The CS-12's are the same power as the recommended Futaba's and are available with metal gears so they could have been used all over for about a .5 oz. per servo savings over the CS-35's. If I had it to do over I would opt for those servos in the wing at least. All loaded up, the Spirit Elite required only 1/2 oz. of additional nose weight to hit the target C.G. That is why I was a little sorry that I had pre-installed the 1.5 oz. of weight in the nose block that is now inaccessible should I decide to use a larger battery pack or try a more aft C.G. location. Final ready-to fly-weight was 40 oz. versus a kit target of 32-36 oz. Again, using micro instead of the mid-size servos would have narrowed this gap about 2 oz.  Landing using The "Crow" Position for Flaps & Ailerons. Great for spot landings. Flying: All control throws were programmed to the recommendations given in the instruction manual. The Spirit Elite was ready to fly in January, but Mother Nature decided to cover everything with snow for a couple months, postponing test-flying until mid March at the season opening club contest no less! I had time for a couple test flights before the start of the meet; I at least wanted to get a launch before it mattered and to get it leveled on all four corners. Not to worry; the Spirit Elite went up nice and straight, and responded well to some nudges from the rudder to correct its path. For the first release I simply flew it off the top of the line. Control response felt pretty good on all axes; applying flaps resulted in a slight nose-down tendency indicating to me that the elevator compensation was right on target. Speed retention through thermal circles was satisfactory. All systems were go for a little more aggressive flights. Starting with the second launch I set the flaps to their launch mode (about 1/4" of flap and half of that in the ailerons) and started working on maximizing the launch. I started riding both the winch and the elevator to get a little more altitude. I quickly became so confident in the Spirit Elite that I even shared it with another flier who had damaged his bird on his first round flight. All in all a good first day out. Just one week later we had the second meet of the season and I again flew it in the 2M event in the morning. The Spirit Elite was doing its job - better than the pilot was! This time, with a challenging downwind set-up of the winches, the good launch behavior continued to manifest itself, and the fast 7035/7036 airfoils really show their stuff coming off the winch zoom. The Elite penetrates well yet does a pretty good job of marking lift. I started messing around with some reflex and camber settings. Varying these has a very powerful impact on the characteristics of the Spirit Elite, a touch of flap lets it float like a butterfly, a touch of reflex lets it sting like a bee! This lets the flier take control of the situation and maximize whatever the air is willing to give up. The good handling manners continue to show up when it is time to land. It's easy to fly it home with partial flaps to keep the speed under control. With full flaps it virtually stops, making it real easy to set it on the landing spot rather than having to dork it in. Looking ahead, I plan on moving the C.G. around a little just for cause/effect, and I'm going to continue to explore the camber and reflex settings.  Conclusion: With the Spirit Elite, Great Planes has updated a great bird to be truly competitive again. The built-up structure takes more time to build than some of its pre-fabbed competitors, but the cost is much lower too. The builder will be rewarded with a great flying, fully contemporary sailplane. Photos by Dennis Adamisin. Reprinted with permission.May, 2001 R/C Modeler Magazine Editor: Dick Kidd
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