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This item is discontinued. GREAT PLANES GIANT EXTRA 330L 
Type: Giant Scale Aerobatic COMPLETED MODEL CHEERS JEERS Full scale aircraft manufacturers, specifically the ones that offer small, highly aerobatic one and two place aircraft used in competition flying, are constantly trying new and different options in order to allow their planes to perform to their maximum capability. Changing wing location, tail surface position, and engine selections are just a few options that have been used to upgrade existing aircraft without having to design an entirely new airframe from the ground up. The popular and successful Extra series of planes, manufactured in Germany, have been making many of these modifications to keep up and surpass the competition. The addition of a 330 HP engine, along with lowering the wing, resulted in the Extra 330L, a two place enclosed cockpit monoplane that seems capable of keeping up with every plane it faces in aerobatic competition. Since the 330L follows in a long line of successful Extra designs, it seems only natural that the R/C world should also keep up with the times, and have a large scale model of the Extra 330L. That's exactly what Great Planes Model Mfg. thought, so they designed and produced a 1/3 scale version of the 330L. It differs from most similar size models since this one is an all wood kit. There is no type, powered by an 85 cc gas engine, and covered with MonoKote, weighed just a shade over 18 lbs. That's almost 9 lbs less than many of the other planes in this size range. We all know less weight equals better performance, and Great Planes did a fine job in reducing the weight, but more on that later. The Extra 330L kit arrived in two large boxes. The normal size box contained a tropical rain forest worth of balsa sheets, sticks, laser and die cut ribs and formers a formed aluminum landing gear, and a small bag of hardware. Also inside were asset of rolled plans that must be taped together (for obvious reasons), and Great Planes' typical, high quality, illustrated instructions. The second box, a mere 18x18x36" long, contained a huge formed clear plastic canopy, and get this! - a genuine one piece fiberglass cowl and wheel pants set! This is a first for Great Planes, and certainly a first in the industry of mass produced, large scale, all wood kits. The cowl, incidentally, is about as big as a medium size trash can! (If your engine won't fit in this, then put it back in your truck and get a model airplane engine!) There's a lot of material in the boxes, but not as much as one would think necessary to build a plane this large. Just about all the wood parts are contained in the larger of the two boxes, and I defy anyone to successfully replace all those pieces, and still get the box closed. Many of the laser-cut part sheets are shipped between balsa sheeting, just to keep the parts from falling out! Most of it was beautifully done, but one sheet of laser-cut ribs wasn't cut all the way through, so a little work with a hobby knife was needed to remove the parts. Some of the die-cutting wasn't absolutely perfect either, and the knife was needed again. All of the sticks and sheets (and there are plenty of them in this kit) seemed to be of good quality. According to the instructions, several balsa sheets must be bent around a rather sharp curvature, so very soft balsa is an absolute must in this case. I spent a full evening just inventorying all the parts, labeling them when not already marked, and punching them free of the sheets, or removing the cut-outs. I weighed the scrap wood, measuring a full 2 lbs. of just plywood. Some of the parts had very cryptic names, like "aft top stab spar" and "left forward center box side". I'm sure it'll all make sense as time goes by, though. Most of the construction will be done using yellow carpenter flue, with Zap used for quick assembly. Pacer epoxy will be used in high stress areas. As I have noted in the past, all adhesives should be used with adequate ventilation. Construction begins with the stabilizer halves, the elevators, fin, and rudder. Great Planes designed the Extra with plug in stab halves supported by an aluminum tube, with the elevator servos mounted on the bottom of each stab panel. The stab is more than 42" wide, so removable stabs will make transportation a little easier. The stab skins are assembled, and then the ribs, spars, and shear webbing are assembled dry for alignment, and glued only after everything fits in proper alignment. I found that the slots on many of the ribs and webs were die cut too wide, so I questioned their size to Great planes via email. See the wing comments below for their response. The elevators are built while the ribs are still joined to the stab halves. Everything is sheeted and sanded, hinge blocks installed, and sheeted on the other side. Once the elevators are cut free, the stab halves are just about complete except for final sanding. The fin and rudder are built almost the same way, but they use a leading edge jig to keep things straight. Balsa sheeting is applied to one side, hinge and horn blocks added inside, and sheeting applied to the other side. We then have a set of complete tail surfaces. Incidentally, the instructions also give the builder the option of adding additional balsa to the hinge lines of the stab and fin, to be beveled for more than 45 degree of control throw, as needed for 3-D aerobatics. The wing panel assembly is much like that of the stab and fin, but on a larger scale. Three die cut shear webs connect the die and laser cut ribs together, which are all held in alignment by a leading and trailing edge jig pinned to the board. The wing joiner tube is inserted into the holes in the first six laser cut ribs, and glued in place after the ribs are secured. The builder is warned not to use thin CA on the phenolic tube, because it might penetrate too far, preventing the aluminum joiner rod from inserting all the way. I used yellow carpenter glue to secure the tube to the top and bottom spars, and all ribs. Some of the slots in the ribs and webs are a bit too large size, just like those I found on the stab ribs. I contacted Michel Cross, designer of the Extra 330L, and asked about the oversize slots. His answer seemed fair enough, that the slots were made a little large to keep the ribs and webs from splitting or bending during assembly. He said as long as two sides of each joint was secured with glue, the structure would still be strong and light. So, that's how I built the wing. I put all the ribs, webs, spars, and jigs into place before applying any Zap, just like the instructions say. When it came time to apply the glue, I made sure each joint was touching on at least two edges, and then added a drop or two of thin Zap. Once all the joints were secure, I went back and added a drop of yellow carpenter glue to any open spaces in the joints. The Extra 330L wing panels are sheeted only on the leading edge and center section. The ailerons are assembled while their ribs are still a part of the wing panel. They're cut free after sheeting, at which time the leading edges are added and shaped. The builder is given the option of using either two or four aileron servos, and all parts are included for either option. I added the extra servo mounts and control horn plates, in case I later decide to go with the four aileron servo option. The completed and sanded wing panels, minus covering and servos, weighed a little more than 1.3 lbs, each, light enough, but not as light as the ones I saw on the prototype model at the Toledo Expo. Great Planes must use some really light balsa on their prototypes! Next come the fuselage, built from a framed box surrounded by formers, stringers, and sheeting. The full length box is built from several laminated plywood sides in front, and plywood tail supports connected by hardwood sticks that are made from two 36" long pieces Zap'd together end to end. It just barely fit on my 80" workbench! Cross braces are then added, and a second side is built over the first. The two sides are then positioned over the plans, and the plywood formers are Zap'd in place while making absolutely sure everything is perpendicular to the building surface. Then more cross braces are added. The instructions state that you should not be alarmed by any movement found in the structure at this time because the stringers and sheeting still to be added will make everything solid. I didn't notice any such movement, and I believe this fuselage to be strong enough to handle just about any power plant. (No, that doesn't include that truck engine you've been eyeballing!) I had to cut about 2" from the bottom of the supplied 1/2 " plywood firewall, at an angle to clear the Bisson Pitts style muffler on my Zenoah G-62. Those of you fortunate enough to be using a twin cylinder engine should not have this problem. The engine box on the Extra 330L kit is purposely made quite long, and the instructions tell the builder how to determine the length of the fuselage sides, depending on your choice of engines. Right thrust is built into the structure. The main gear is fitted into place, followed by aligning the wing panels to the fuselage. The aluminum tube joiner fits into a phenolic tube that attaches only to the center fuselage box. The rounded sheeting outside the fuselage will have openings cut for each wing panel to slide through. Once the wing tops are positioned to the tail post, the wing tube is epoxied to the plywood box, and everything is permanently in place. The two horizontal stab halves are joined to the fuselage in a similar fashion, making sure the stab is parallel to the wing, and perpendicular to the fuselage centerline. The recommended Ohio Superstar Haigh style tailwheel assembly installs easily and adds to the scale look of the Extra 330L. Now is the time for making square things look round. The side formers and stringers are Zap'd to the outside of the square fuselage inner box, and sheeting is applied to the front 2/3 part. With one side sheet in place, the wing tube is inserted and a clearance hole is cut into the side sheeting. The wing panel is then fitted over the tube, and a hole is cut into the side sheeting to allow the wing to fit through and touch the inner fuselage box side. Great Planes shows a neat trick using a single edge razor blade on a stick that is used to cut the hole in the sheeting exactly the size of the wing outline. There will still be a slight gap, however, since the root of the tapered wing is a bit larger than the wing is where it stops in the fuselage cutout. All in all, though, it fits pretty well. The front turtle deck is then added, along with the engine box bottom, and top access hatch. All that remains now is the rear turtle deck, consisting of several die cut formers, some balsa stringers, and a very large section of edge glued balsa sheets. This large sheet is assembled and allowed to dry overnight. Then it's moistened...no, it's soaked with hot water and ammonia, and placed over the formers. Wet towels are then draped over the sheeting which pulls the balsa down over the rounded structure with the help of gravity. This is left to soak, form, and dry, for at least 24 hours, after which the formed deck is just about ready to be trimmed and glued to the formers. I considered the use of 1/32" plywood here, rather than balsa, just to hasten the process, but the supplied material worked well. Just make sure that the joints are all attached securely, since the turtle deck provides a lot of strength to the fuselage. The fin is then fitted to the top of the rear turtle deck after cutting a suitable slot in the balsa. Make sure the fin is perpendicular to the stab, of course. The cockpit base is then fabricated from balsa sheet and a front and rear former. The clear plastic canopy is supposed to be permanently attached to the edges of this base, but I just can't bring myself to apply flue to such a beautiful canopy. Great Planes also recommends against using traditional canopy adhesives, as it may not be strong enough. To solve this conflict of interests, I put some scrap hard balsa sticks on either edge of the canopy base, beveled them to match the contour of the fuselage sides, and attached the clear canopy to these sticks with a handful of servo screws from Micro Fasteners. These screws have a 2-56 Allen socket head with a built-in washer, and threads down their entire length. They're designed for mounting servos, but I've found literally dozens of other handy uses for them. Micro Fasteners is a regular advertiser in the magazine, and they have good prices on some very good products. If you don't have their catalog, order one today! My canopy assembly was then secured to the top of the fuselage with two dowels in front and two small bolts through the sides at the rear. The canopy should be masked and painted to match the fuselage color. I applied a coat or two of UltraPaint from Goldberg, which matched beautifully. The cockpit floor was painted using a product called Trunk Paint, used to paint the inside of automobile trunks. It has some texture to it, and actually sprays out of the can in two colors. I used gray with white spots. The huge cowl is fitted to the front of the fuselage, and cutouts are made for the cylinder head and exhaust pipes. If using a twin cylinder engine, you won't have to make so many cutouts, but all installations require the bottom of the cowl to be opened up for proper air flow for cooling. The cowl is attached using 17 small wood screws, which I replaced with more of those great little Micro Fasteners servo screws. (See, I told you they were handy to have around!) After a hole for the fuel filler was drilled in one side, the cowl was ready for primer and paint. It was now time for sanding and preparation for covering. All the low spots were filled using Model Magic Balsa Filler from Dave Patrick Models. This has been a long-time favorite of mine, and now it's available only from Dave Patrick Models and local hobby retailers. There are other products that look the same, but I don't think they work as well for models. With all the little builder induced dings and dents filled, I smoothed out the entire plane with some 400 grit sanding pads, and then removed the dust with a shop vacuum and tack rags. I used Goldberg UltraCote to cover the Extra 330L, using two rolls for the wings, two more for the fuselage, and almost two rolls of their new checkerboard film on the control surfaces. Covering a model this large requires a bit more space to move things about, but the actual covering operation is actually easier, since the larger pieces are easier to cut out and handle. The firewall area and fuel tank mount were coated with thinned epoxy, and Goldberg UltraPaint was used on the cowl and wheel pants. There's a long story behind the graphics package I used on the Extra 330L. Let's just say the #90 NASCAR Winston Cup race car, its owner (Junie Donlavey), our esteemed editor (Gordon Banks), and my family (the Pettit clan) all have a lot in common concerning this particular finishing scheme. So, I ordered a set of graphics from Dennis Kirby, from Kirby's Kustom Vinyl Graphics, using paint and color references taken from several of the popular NASCAR oriented websites. Dennis made up the graphics for the wing, fuselage, and cowl, and I got a set of "fender sponsor" decals from New Era Models, who specializes in 1/4 scale race cars. Now, as with all the models I build, since it's 95% complete, there's only 90% of the work left to do. The G-62 engine and kill switch were mounted, the throttle servo and linkage installed, receiver and battery mounted, rudder and tailwheel linkages built and installed, canopy and cowl mounted, and... Whew! The list goes on and on. You know what I mean. I used a complete set of servos from Servos Direct, consisting of four coreless 104 oz./in. on the ailerons, two on the rudder, two more mounted on the bottom of the stab halves for the elevators, and a single standard size on the throttle. Instead of trying to reverse one of the elevator servos, I got an EDR-106 Servo Reverser from ElectroDynamics. This neat little device will reverse a servo without the bother of any screwdriver adjustments caused by heat, aging, or servo type, and I've used them before with good success. I also used the ElectroDynamics EDR-111 Pow'r Bus Pro Servo Isolator, which allows the use of separate batteries on the receiver and the servos. I'll use a 600 mAh battery for the receiver and a 5-cell 2000 mAh battery on the servos. All control linkages were 4-40 rods and clevises, made as short as possible for direct control. A plane like the Extra 330 just begs for some sort of smoke system, and there are a number of choices I could have made. I already had the Bisson Smoke Muffler, but lacked a pump system to get the oil from the tank to the muffler. After some research, I chose the B&B Specialties Super Smoke Pumper. The system consists of a pump that's powered by crankcase pressure from the engine, a control valve, and a crankcase fitting, along with the required lines. I sent my G-62 to B&B Specialties for the drilled and tapped hole in the crankcase to provide pressure for the Super Smoke Pumper system. Then there's no extra battery or wiring to carry, no maintenance or battery charging, and best of all, the pump output varies proportionally with engine speed. The smoke control valve mounts through the firewall, and requires only a standard size servo for operation. I added a second fuel tank for the smoke fluid, installed all the necessary plumbing, and was ready to run again in less then an hour. The final weight of my Extra 330L is just over 23 lbs., and I can't even imagine this model, in flying condition, weighing only 19 lbs., as indicated as the lower weight range in the ads for this kit. On the other hand, I can see where one of these kits could be built with a full paint, job, a large twin cylinder engine with a on board ignition system, smoke system, pilot figure, scale details, and some of that 'beefing- up' that so many builders like to do, resulting in a plane that approaches 30 lbs in total weight. After running the engine and checking all the systems in the backyard, it was time to haul the Extra 330L out to the flying field. I took an afternoon off from work, packed up the Extra and all the support equipment, picked up my photographer, and off we went. It was a beautiful day, but there were only two other pilots at the field, giving us almost unlimited flight time. After taking plenty of ground photos, we completed a very through pre flight inspection, filled the gas and smoke tanks, and range checked the radio with the engine off and when running. When we could find no further excuse to delay the first flight (and believe me, we tried!), it was time to put this giant into the air. After some taxi testing to make sure the ground handling was good, I pointed the nose toward the far end of the runway, advanced the throttle to half, and watched as the model accelerated, lifting the tail almost immediately. Once the model began dancing lightly on its main wheels, I applied full power, and the Extra 330L took to the air. I'd used less than half of our 300' grass runway. A climbing right turn took the Extra back across the filed, and only one click of left aileron trim and one click of down elevator trim was needed to allow the Extra to fly straight and level, hands-off. I began to relax a little. I reduced the power a bit, and rolled the plane right and left, finding the low rate aileron setting to be a bit too low for my tastes. I switched to high rates, which increased the roll rate dramatically. Rolls were still axial, however, and without any noticeable pitching or diving. Despite the model's large size, I could get almost two complete rolls per second. I increased the power and entered a moderate size loop, finding that the G-62 was doing all it could do on the up-line, but didn't phase the Extra. The loop was big and round, despite the speed being a little slow. When timed correctly, a stall turn allows the Extra to pivot on its center point. Several more maneuvers were done with equally excellent results. I began to relax a lot more now. I then climbed to a safe altitude, reduced power, and gradually applied full up-elevator. The model never did stall, but it did start to come down with its nose up at an almost 45 degree angle, quite like the "Harrier" maneuver performed by top aerobatic pilots. Back at altitude, I tried a spin. The Extra spiraled slowly downward, approaching a flat spin attitude. As soon as I neutralized the controls, it straightened out and started to fly again. Before beginning the landing sequence, I performed a couple of pretty nice knife edge passes, with only about half of the available rudder needed! The G-62 didn't have enough power to pull the nose up into a knife-edge loop, so we'll have to leave those maneuvers for flyers with more powerful engines. Then I made a couple of low passes for the camera, and turned on the smoke system. The passes were fine, but there wasn't much smoke coming from the muffler. Instead, most of the smoke seemed to be coming out the bottom of the cowl! I suspected that the neoprene hose to the muffler had slipped off the fitting, which meant that the smoke fluid was spraying all over the engine. My first landing was uneventful, resulting in a fast but smooth three point touch down. Back in the pit area, we discovered that the smoke tubing had indeed split and come off the muffler fitting. We were unable to repair the line at the field, so smoke testing had to be postponed. But no other problems were noted, and the 12 minute flight had used only about 10 oz. of fuel. I drained the smoke tank, and filled the fuel tank for another flight. I had also noted that the engine seemed to be running a little on the lean side, so I adjusted the carburetor a bit richer. The second and third flights were even better than the first, with pilot confidence increasing after every maneuver. I tried a full power vertical climb, and it went well enough until the G-62 just ran out of steam at about 500'. I tried to hold a hover and perform a torque roll, but more power will be necessary to complete that maneuver. Inverted flight is easy, with practically no down-elevator needed. Snap rolls, both positive and negative, were smooth and crisp, and stopped immediately once the controls were neutralized. More low passes and knife edge flight were done, and all was proceeding quite well until the third landing. I somehow misjudged the runway center line (this is a big airplane!), setting the Extra down in tall grass. Only minor cosmetic damage was done, but the propeller became a paint mixing stick. The B&B Specialties smoke system worked perfectly once a small problem was addressed. The Bisson smoke muffler uses a rather large diameter fitting on which to attach the smoke fluid delivery line, and the neoprene hose provided in the B&B system was just too small to survive all that stretching and heat. I replaced the line with automotive vacuum hose, and so far it seems to be working just fine. The smoke certainly adds to the visual presence of the big Extra. After several more flights were completed, I noticed that the wing and tail bolts seemed to be loosening. As it turned out, the threads in the aluminum tubes were actually stripping out, leaving only the bolt and the wooded block in the wing holding the airplane together! To effect a cure, I used a short section of hardwood dowel inserted into the stab tube, after drilling and tapping the mounting holes. I hardened the threads in the wood with a drop or two of thin Zap, and retapped the threads after the glue cured. I also used a section of dowel in the wing tube, also Zap'd in place, drilled and tapped for a larger 8-32 bolt. I now believe the wing and tail are secure for a long time to come! As more and more flight testing continued (what a hard life I lead!), the big Extra 200 continued to impress everyone involved. More power would have been nice, but the G-62 was enough for sport aerobatics and everyday sport flying. It only lacked authority in true vertical maneuvers, so those were simply avoided in subsequent flights. The smoke system was now working perfectly, producing billowing clouds of dense white smoke, and even the pilot because accustomed to the general performance and impressive capabilities of the big Extra. I'm really looking forward to flying this model at some of the events in my area. CONCLUSION: I think the Great Planes 1/3 Scale Extra 330L kit is well worth the price and construction effort, with excellent materials, plans, and instructions. It doesn't take a lot of time to assemble, and the builder can be ready to cover the model in surprisingly short order. The Extra 330L is a light model, but not quite as light as described in the literature. I think it could be build with a final weight in the 21 lb. range, but not with a smoke system and tank, extra graphics, and larger, heavier servos. My 23+ lb. Extra performed well with the G-62 engine, but more horsepower would certainly improve its vertical performance, and maybe reduce the noise level as well. The plug in wing panels and stabilizer allow easy transportation, but be prepared for hauling a very long fuselage (mine is nearly 7 1/2 feet long!). My trailer turned out to be just perfect for the Extra. Flight characteristics of the Extra 330L are surprisingly crisp and clean for such a big model, and several spectators commented that the plane flies at a remarkably low speed. This, I feel, is mostly an optical illusion due to the model's large size. The Extra is obviously flying at a speed perfect for aerobatic demonstrations. It can, however, be slowed to what seems hardly more than a walking speed, with no apparent loss of control authority. Its aerobatic potential is limited only by pilot ability. Frankly, the Great Planes 1/3 scale Extra 330L seems to be able to do it all, and in fine fashion. It certainly suits my flying style well, and unless presented an obscenely generous check in trade, I expect to be flying it for a long time to come. Reprinted with permission.February, 2001 R/C Report Editor: Gordon Banks
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