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The Super Sliver SP400

Joel Maxwell reports on the Sliver, a top Speed 400 racer that doubles as a nice sport plane, plus Joel includes some tips on how to be competitive at pylon racing.

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Specifications:
  • Wingspan: 34 in.
  • Wing Area: 158 sq. in.
  • Length: 21.5 in.
  • Flying Weight:
  • Airfoil: semi-symmetrical
  • Power system: 6v Speed400 for class racing, Astroflight brushless 020 or Aveox brushless 1005/3Y for fast sport flying
  • Speed Control:  Castle Creations Pixie 14 for Speed 400, Astroflight controller with brushless 020, Castle Creations Dragon 35 with Aveox 1005/3Y
  • Cells: 7 500AR or 600AE cells (600AE only with Speed 400)
  • Radio: Hitec Focus 4, 2 HS-55 servos
  • Price : $
  • Manufacturer: Michigan Speed Solutions

 

Background

This review is for those of you who would like to try a high performance Speed 400 racing airplane, but with very little high performance airplane construction experience. Building the Super Sliver is straightforward and only requires some high performance airplane building techniques, which I will try to cover.

First of all, I am assuming that you have tried an easier type of pylon racer, such as a Ace Simple 400, or the larger Speed 400 Twister, or maybe a Bare Bones, or even a Pylon Buster if you can latch on to one, which in my opinion, is the best way to start racing. The easiest way to learn about Speed 400 racing is to talk with pilots in your area. All Speed 400 pilots will be glad to help you because they are always looking for new pilots to give them more competition. Racing is a great sport, and will give you as much enjoyment as any other facet of the hobby.

Now that I have that out of my system, I can get down off my soapbox and tell about this great little speed 400 racer. The designer, Archie Adamisin I I I , a member of the US FAI F5D team, first introduced me to the Super Sliver about two years ago when he gave my son one of the original airplanes he was racing. The Super Sliver is a purpose-built racing airplane, which by the way won the NATS 2000 Speed 400 racing event. It was originally designed and kitted by Archie Adamisin of Adamisin Racing Concepts, but due to conflicting priorities, the rights to the design and the kit were recently purchased by Dave Campbell of Michigan Speed Solutions. You can contact Dave by e-mail at: C. David Campbell [cdcampb(at)ismi.net] or call him at (248) 624-7914.

Of all of the competitive Speed 400 racers available today, the Super Sliver has one of the largest wing areas at 158 in2, and one of the easiest fuselage cross sections to install the radio gear and battery into. Here are a couple of pictures showing my son’s SP400 racers, the Adrenalin, Skat, Sliver and Dago Red. (The Sliver used in this review was omitted from the picture.) The Sliver is the orange, black and clear airplane. It is very obvious that the Sliver wing is much larger. The fuselage is a little larger under the wing, which makes installing the battery a breeze. I have found that the smallest wing does not make the best racer. Speed 400-pylon racing must begin with a solid hand launch, turning left very tightly around a pylon course 10 times, and then a controllable landing. Highly loaded, low lift wings have trouble with the whole concept.

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Kit Contents

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The kit contains a very well done colored or natural fiberglass fuselage, a set of wing cores, and a very complete set of instructions. Also on top I found a very attractive Super Sliver adhesive-back Mylar decal.

The kit contents may seem a little shy of parts if you are used to sport airplanes, but this is how most high performance kits are produced. There is a very good reason for this. One, this allows the builder to select the grade of wood he or she prefers, and second, this allows the kit manufacture to save cost of producing the kit. The remaining materials cost less than a couple of bucks.

 

Construction

The first step to building any kit is to review the manufactures assembly instructions and recommendations. What is unusual about this kit is the very detailed instructions that cover every aspect of building and trimming this airplane for racing. Typical high performance racing airplane instructions are straight to the point and most details are left up to the experience of the builder, but not this one. As with any high performance airplane, the instructions require the builder to make some decisions up front about which include tail design, type of motor, and final finish they prefer. Having been involved with racing airplanes for several years now, I had an idea where I was heading as far as construction techniques. I will talk about the options as we begin building.

The instructions start out with the fuselage, but I prefer to begin racing airplanes with the wing. Let me explain why. Racing airplanes require accurate alignment to track and fly well. As the speed increases, the airplane becomes more sensitive to misalignment of the flying surfaces. To retain the most accurate alignment and balance, the wings and tail assembly are aligned to each other and fuselage all at the same time. Before the fuselage can be completed the wing saddle must fit the wing, and tail must be aligned to it. The kit designer has taken great care in the design to assure the v-tail alignment, but additional care must still be taken. The second reason I like to start with the wing is that while the wing skins are curing, the fuselage can be worked on, saving time at the workbench.

Wings

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The wing design has what is called a lapped trailing edge, which means no tailing edge stock is used, only the wings skins, eliminating the step of fitting trailing edge stock. Before removing the wing cores from the husk, take a marker and put a couple of marks on the ends of the cores. This makes aligning the assembly very easy when the time comes. The instructions call for a 1/32" plywood spar, which I ran 6" into both wing halves. Place the spare at the high point in the wing; the wider the spare, the stronger it will be. Plus, when we are done we will have produced an "I" beam in effect, which is the strongest shape we can create easily.

The first step is to very lightly sand the cores using 220 grit sandpaper. The idea here is to only remove the fuzz. You will notice the trailing edge will get a little jagged on the edge. I usually remove about a 1/16" to make sure that the foam is smooth and flat. If a trailing edge would have been required, you would not cut the cores or you would be reducing the size of the wing.

The next step is to attach the skins to the cores. You can prepare your skins by spot gluing them together. Remember the skins are only 1/32" sheet balsa, so any sanding will weaken the wing. The strength of the wing comes from the spar with fiberglass tow and the wing skins. The core is used only to give the wing its shape. I have been building racing wings for several years now for Q500 and Q40 racing airplanes, and the technique I use for the sp400 wings is identical as for the Q500 racers, It will produce a wing as strong as by any other method, but lighter. First, you will need to cut eight pieces of .5 - .6 oz fiberglass cloth 1.0" wide, the length of the wing panel. One piece is placed on the wing at the high point directly over the spar top and bottom, and the second at the trailing edge. Remember that this wing uses a lapped trailing edge, so the core is not the trailing edge. The trailing edge continues about 3/8" past the end of the core.

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Here is the secret to very strong and light wing: the adhesive I use is Titebond. Titebond when cured adds very little weight, plus it is impossible to separate the wood from the core. The method I use is very simple. Using a 1.0" diameter yellow foam roller, spread the adhesive all over the wing cores and skins. Place the fiberglass cloth on the core over the spar and roll over it, pressing the adhesive through it. For the trailing edge cloth, locate it on the skins. I have also used this same method with carbon fiber tow, which works just as well. You should have a nice, even, thin coat just thick enough that you can see through it. Now place the skin on the core, aligning to the leading edge with about 1/16" – 1/8" overlap. Place this side in the husk and repeat the steps for the remaining four core sides. After everything has been assembled, place the cores between two pieces of flat plywood and weigh it down. I have 6 large beam clamps that I use. I tighten the clamps until I compress the assembly by about 1/16". Any more and you will flatten the wing, changing the airfoil shape. Note that the trailing edge is straight and flat. On larger wings I use two pieces of " aluminum angle (purchased at the local hardware store) clamped to the trailing edge using small spring clamps, which you can buy for about $.50 each. Allow the wing to cure for at least 24 hours. After the wing has cured, remove the cores from the husk and inspect them. Make sure that the core has been adhered 100%. Some of the adhesive may have wicked through the skins; just break it away and sand the foam off.

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Just to show you the bonding quality of the Titebond, here is a picture of a wing section 1/16" thick cut on the band saw. The bond between the wood and the foam is excellent with no signs of delaminating.

Using a razor plane and sanding block, trim the leading edge back to the core. Look down it to make sure it is straight and flat. Now you can attach your leading edge and cut the wing to the final width. At this time you will need to cut the wing to length and sand a very accurate center joint. It is very important that the joint be as perfect a match as possible. When sanding the center section, don’t forget about the spar, as you are sanding. I do use 24-hour epoxy to join the wing halves together because of its high shear strength properties compared to Titebond. I use masking tape to pull the wing together and align the leading and trailing edges together. While the center is drying, glue on the wing tips using Titebond. After the wing has cured cut the wing to the correct width. Cutting and sanding the wing to it’s finished width and size at the final step eliminates the risk of any misalignment or differences in wing panel size.

Now we can start sanding the completed wing. The idea here is to sand as little of the skins as possible, except at the trailing edge, which can now be feathered almost sharp. Since we added the cloth under the skins, this makes for a very stiff and hard trailing edge. One of the big topics in racing circles is what should the leading and trailing edge look like. Well, here it is guys, from the top racers in the country: the leading edges should be rounded, not sharp, and the trailing edge should be as sharp as you can make it while retaining good stiffness. This applies to the wing only; the tail surfaces should be sharp on both leading and trailing edges.

Next, mounting bolt hard points must be put into the wing. For mounting the wing I used two 8-32 nylon screws placed about 3/8" from the leading and trailing edge. Using a sharp drill, drill a 3/8" diameter hole all the way through the wing. The next step is to fill the hole with an epoxy-micro balloons mixture. This is easy if you place tap on the top of the wing and fill the holes from the bottom of the wing. When the epoxy dries it will be very easy to sand, but use a very sharp file or you will remove wood also.

On the Sliver I do add a piece of .5oz fiberglass cloth about 4.0" wide at the center section top and bottom. If you have a very good center section joint, cloth on the bottom only will also work. The cloth has two functions: one is to reinforce the center section and the second is to give the wing a hard, non-compressible surface to mount to. I use 24-hour epoxy and a credit card to remove as much of the epoxy as possible, feathering it out at the edges. When cured, you should only need to do a very little sanding. The next step is to drill 1/16" diameter pilot holes through the screw mounting locations. This will allow them to become pilot holes for the threaded wing mounting holes. This will also allow you to drill a 1/16" diameter pilot hole into the fuselage and insert a 1/16"dia dowel which will act as pivot point for aligning the wing when it comes time.

The final construction step in building the wing is to cut the ailerons and add the torque rods. First, locate the ailerons on the wing and very carefully cut them out. On SP400 airplanes I use a live hinge produced from the Monokote wing covering, so only taper the leading edge of the aileron, like it was a flap. You will only need about 1/16" draft. No cap strips are required since this area of the trailing edge was glassed, and no fuel soaking can creep up under the covering (one of the nice aspects of using electron power).

The torque rods are bent to shape and exit holes are placed in the wing. Draw a straight line from the aileron cutout to the wing center section where the torque rods will exit. Using a sharp razor, remove only the bottom skin and just wide enough to slip in the torque rod. Save the piece of skin you removed; you will replace it after the rods have been installed. After trial fitting the rods, mount the wing to the fuselage, holding it in place with tape. Next, using epoxy, place a small amount of epoxy around the torque tube and replace the skin. When completed the wing will have retained its correct shape at the trailing edge, and very little if any finish work will be required. The wing is complete except for adding the final mounting hole diameters and covering. The ailerons will be added during covering.

V-tail

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The v-tail is pretty straightforward. First step is to pick the desired shape. I have tried about every shape you can think of and found that the most import part of producing a v-tail is assembling it straight. I probably do this the hard way, but I can guarantee that when I am finished, it is straight and right. First I use medium balsa for the tail because I like it to be stiff. The tail is small enough that the weight penalty is almost negligible. Draw the finished outline on two pieces of balsa cut square. Don’t forget to add cross grain caps at the tips; it is very important for strength and to prevent warping. Next bevel the edge that will become the center so a good joint can be made. I found that 110 seems to be the best angle, so sand a 55 angle on each half. With the tail still square, I place the wood on the leading or trailing edges and glue the two halves together, making sure the pieces are vertical to the work bench and parallel to each other. This does two things: First, it aligns the stabs to each other so no twisting can take place.  Second, it creates a perfect square bottom edge to mount the tail with. If you wish, you could also sand the bottom of the joint on a disc sander while everything is still square to guarantee a perfectly square mounting surface. Now the tail can be cut to the final shape. Do not cut the elevators away from the stab until you have finished sanding the leading and trailing edges to a sharp edge. To be consistent with the sanding, take a marker and draw a line " back from the leading edge top and bottom. Sand the wood from this line to the leading edge until the leading edge is sharp. Do the same for the trailing edge. Leave the rest of the stab flat in the middle; only finish sanding is required. This makes for a stab that has a good, flat mounting surface. After the sanding has been completed, cut the elevators free. Sand a slight bevel to the leading edge, allowing the elevator to fit tight at top with clearance for down deflection. Remember, we are going to need very little deflection, so only a slight bevel is required. Drill a hole in the elevators to accept the control wire and you are done. We will attach the elevators with the covering material at the finishing stage.

The elevator control horns are rather unique in the fact that they are inside the fuselage to reduce drag. This has become the standard for almost all racing airplanes. The control horns are really very simple once you understand the concept. First, take a standard size Du-Bro plastic kwik-link and remove the pin from the one side and drill a hole the same size as the other side all the way through both sides so that you could pass a wire through it. Second, using music wire, bend two horns with about a 1/16" bend that will allow the two wires to be placed inside the kwik-link side by side with the 1/16" leg through each hole. Place a piece of fuel tubing over the link to hold it together. Ok, now about 3/8" away from the first bend, make a 55 bend on each wire matching the angle of the stab. About a 1" away from the last bend, make a 90 bend like a standard elevator horn and you are done. The most important part here is to make sure both horns are the same or the elevators will be off when you are done. The final assembly will take place when assembled to the fuselage.

Fuselage

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We can now finish up with the fuselage. The fuselage is quite simple, needing only a few steps to complete. Before assembling the fuselage, wash the fuselage with warm soap and water to remove any mold release and wax. Inspect the fuselage for any bad joints or thin areas where the epoxy did not flow during the fabrication. If every thing looks good, move on. If not, apply epoxy and cloth to the weak areas on the inside of the fuselage. All three Sliver fuselages that I've seen were well done.

Begin assembly by trimming the extra cloth from the wing saddle area. Be sure to leave about 3/8" of wing saddle on the sides, and at least " – 1" on the leading and trailing edge for wing mounting bolts. If you cannot get your battery in because the opening is to small, carefully remove material in small amounts until the battery can be placed inside the fuselage. Do the same for the tail mounting location by removing the glass from the tail mounting area, allowing the bottom V of the tail to sit properly. Be very careful not to remove material from the mount edge; remove material from only the inside perimeter, leaving about 1/32" of material to mount the stabilizer. When creating an opening in fiberglass fuselages, be careful not to make sharp or jagged edges, which will cause stress points and will eventually fail. I recommend that you sand all edges smooth, blend any sharp edges, and remove any notches after you have removed the excess glass.

Now that you can get to the inside of the fuselage, install the motor mounting plate. The fuselage comes with the correct thrust angle (0) already sanded into the front of the fuselage; do not try and square it up or you will lose it. Mount your motor to the plate and slide the assembly all the way through to the front of the fuselage. You will notice that it will not pass through the opening; if it does, you have a problem and you will need to contact the Dave Campbell at Michigan Speed Solutions. Next mount your spinner to the shaft as normal and square up the spinner back plate so that the spinner is parallel to the fuselage. Wick in some thick CA around the mount and then remove the spinner and motor. With the motor plate clear, apply a small bead of epoxy around the plate-to-fuselage interface. I try and place the nose plate about a 1/16" behind the front of the fuselage. This leaves a nice area to apply epoxy, creating a solid interface between the mounting plate and the fuselage.

The wing is mounted to the fuselage using two 8-32 nylon mounting screws. Make two 1/8" thick plywood-mounting plates and epoxy them inside the fuselage. Make the plate at least " wide and the full width of the fuselage. You may have to sand a taper to the ends to fit it inside the wing saddle. Place your wing on the fuselage and center it up. I use a good Mylar tape to hold it place. Using the front 1/16" diameter pilot hole in the wing, drill a 1/16" diameter hole into the fuselage. Now, place a 1/16" diameter dowel into the hole. Pivot the wing as needed until the wing has been squared up perfectly with the fuselage and tape it in place. Using an 8-32 tap drill and the 1/16" pilot hole at the rear mounting location, drill through the wing and the mounting plate.

While the wing is still taped on, do the same with the front mounting location. Remove the wing and tap the fuselage, and drill a clearance hole for the 8-32 nylon bolts. Since the two mounting holes were matched drilled, use a clearance drill the same diameter as the 8-32 screw to produce a very repeatable wing-mounting configuration. I also use a flat head mounting screw for the leading edge screw, which can be countersunk into the wing. Be careful to only countersink the screw head below the wing surface. This method for mounting wings is very import for racers that require the wing to be removed every flight. This assures that no trim change will be required from flight to flight. Trial fit the wing to make sure everything is ok. While the wing is mounted to the fuselage, mark the outside of the fuselage onto the wing so we can locate the wing servo.

Mounting the V-Tail

At this point we are ready to mount the v-tail. The v-tail is mounted as an assembly, which includes the v-tail, the control linkage, and the elevator servo. Using a control rod diameter that matches the kwik-link, make a control rod that will locate the elevator servo about 1" behind the trailing edge of the wing. For the review model I used Hitec HS-60 servos, which seem to be high quality servos. Mount the servo on a 1/8" thick piece of balsa about the same size of the servo, using a small amount of epoxy. Remember that when this assembly is completed, it is impossible to work on the servo with out cutting loose the v-tail or cutting holes in to the fuselage. I know some guys who have used double sided tape, but after a year or so they end up wicking CA into the servo because the tape gave out. I also round the bottom of the servo mounting plate to improve the joint between the fuselage and the plate.

Now comes the fun part. Making sure the servo arm is centered, attach the control wire to the servo and slide the assembly into the fuselage until the control rod is sticking out of the v-tail mounting location. Attach the kwik-link to the elevator control arms and place the kwik-link into the fuselage, only exposing the control arms. Tape the v-tail to the fuselage in about the correct location and add the elevators. Make sure the elevators are straight and aligned to each other. Make any final adjustments at this point, because once everything is assembled it is very difficult to bend the control wires without breaking something. Mount the wing to fuselage and place it on a bench so that the wings can be aligned to the bench. I use a set of square steel plates and then place blocks under the rear of the fuselage until the wing incidence measures zero on my incidence meter. With everything in place, mount the elevator to the fuselage using 30-minute epoxy. I check to make sure the tips of the v-tail are aligned to the bench and equi-distant from the wing. I measure from the tip of the wings to the tip of the v-tail. At the same time I also use a 6" bubble level, like those you can buy at the hardware store for a couple of bucks,and measure the incidence of the v-tail. I place the level on the tail parallel to the thrust centerline and put the bubble in the middle. If everything is straight, the bubble should go to the middle on both sides of the v-tail.

Once everything has cured, glue on the elevators using epoxy and tape them so that they are centered. Remove the wing and glue in the elevator servo mounting plate to the bottom of the fuselage, using epoxy.

Final Assembly

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The final step is to mount the wing servo to the wing.  From an earlier step we marked the outline of the fuselage onto the wing so that we know where the constraints will be. Next mount your motor and place your receiver and battery at their approximate locations in the fuselage. Again using a marker, mark the wing where the battery and receiver will be located. On my Sliver I use the Hitec 555 receiver and place it behind the wing in the space between the elevator servo and the trailing edge. At this point I go ahead and Velcro it into place so I know everything is going to stay. I do the same with the battery pack. This should leave a space about 1 " long to mount the wing servo. Some guys like to embed the servo into the wing, but I prefer to mount it on the surface so as not to reduce the structural properties of the wing. I use the small ball links with short control linkages and double-sided mounting tape to secure the servo in place. If you desire you can mount the servo now and finish around it or mount it after you have finished the wing (the method I use).

Finishing

Now is the time to apply your finish of choice. I used Monokote to finish the wings. Everything is pretty much standard except for mounting the ailerons. Before starting, mount the ailerons to the wing using epoxy. The covering will become the hinge, forming a very clean, gapless hinge that will have almost unlimited life with very little drag. Using an X-acto knife, cut the bottom covering very carefully to allow the aileron to deflect. Don’t worry about trying to cover the bottom hinge gap; it is not necessary. Some guys will use hinge gap tape here, but I did not on the Sliver. The v-tail is covered the same way. The review model was painted orange using r/c model car paints so that I could get a fluorescent orange to match the florescent orange Monokote. I then trimmed the model with black trim. It is possible to order the Sliver fuselage in different colors, which I recommend. I have an orange and yellow version, both which are very well done, eliminating the painting and saving some additional weight.

Power System

I have flown the Sliver with the Graupner Speed 400 6volt motor with excellent results using a CAM 4.75 x 4.75. With its very small fuselage cross-section, the Sliver can use the smaller diameter props and take advantage of the higher rpm’s for more speed.

(Patrick Horney):  The model used in this review has been flown with an Aveox 1005/3y and also with an Astroflight brushless 020 sport motor. When I first got the Sliver I was intending to power it with the Aveox 1005/3Y and Castle Creations Dragon controller, but I had just ordered the motor/controller combination and it wasn't available yet. The alternative was to use my trusty Astro brushless 020 that wasn't being used at the moment. With both of the motors I use the same props, either an APC 4.75x4.75 or a CAM 4.7x4.7. I like to use the APC when I  run over 20,000 RPMs; as I think the CAM props tend to depitch when you run them that high. I like to use the CAM props when using the 020 because they seem to be more efficient at the lower rpm's. The 1005 motor with either the CAM or the APC props spins about 23000 rpm on 7 cells. The Astro 020 will spin either prop about 16000 rpm on 7 cells.  I prefer to run the Astro motor on 8 cells (19,000 rpm), but I can't fit 8 cells in my Sliver.  To provide power to the motors I use a couple of 7-cell 500AR battery packs. the 500AR's are able to handle the relatively high currents, unlike some of the other cells in this size range.  Unfortunately, they seem nearly impossible to find at this point in time.

Final Preflight

At this time I installed the motor and speed controller and receiver and checked for the final CG at 2 " back from the leading edge. The recommended controls are between 3/32" – 1/8" for the elevator, and 1/8" – 3/16" for the ailerons. I leave the receiver in the case, and it fits just fine just behind the wing. As mentioned earlier, I use Velcro to hold the receiver and Battery in Place. With a 6 " wing cord at the fuselage, it is one of the most forgiving airplanes when it comes to mounting the battery pack.  Seven cell 500 AR and 600AE battery packs fit up front with about 3" of battery located under the wing for the proper CG.

Flight Performance

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The Sliver has what I think is the best flight performance of any of the SP400 racing airplanes I have flown to date. The pictures above show my current four SP400 racers, an Adrenaline, a Skat, a Sliver and a Dago Red. (The Sliver used in this review was omitted from the picture.) The Sliver has the greatest wing area allowing for the best launch and landing.

The Sliver in this review was given to Patrick Horney, who is interested in pylon racing. Below is his report on flying the Sliver.

(Patrick Horney): When I first got the Sliver, I had been flying a Skat for a couple of months, giving me some experience with Speed 400 racers. I was excited to try out the Sliver and see how it compared to some of the other Speed 400 pylon racers. I found that it flies very nicely and has very friendly flight characteristics. It flies like a sport plane when flown slowly, stalling straight ahead and with no tendency to snap.  Give it full power and it's a rocket, but it's still an easy airplane to fly - a  true go-where-you point it airplane.  I feel entirely comfortable flying it down low at over 100 mph - something you can't say about every airplane.  I like the use the Astro 020 setup for most of my flying - the lower current draw (compared to the Aveox 1005/3Y) gives me longer practice times, yet still with plenty of speed.   When I really want to pump things up, however, the Aveox 1005/3Y is just the ticket!  I only get about 1.5 minutes of run time with this setup on 500AR's, but boy is it fun!  Sometimes I fly this combination like an F5B plane to get longer flight times - I will rocket straight up several hundred feet, shut off the power, and glide through a number of maneuvers.  It's fun to watch this plane go straight vertical!   It's such an efficient flyer that it will glide for a fairly substantial amount of time. 

 

Speed 400 Pylon Racing Setup

Setting up a SP400 racer is fairly easy if you know to look for. During a race you want to be as smooth as possible. I try and set up the ailerons so that the airplane will do a little more than 1 complete rolls in the length of the racecourse. At first this will seem very slow, but you will get used to it. The idea is to place the airplane on its edge and hold it there, so only enough aileron to do this is required. Set up the elevator so that you must give full up during a turn. You want the airplane to turn fairly tight but not tight enough to stall the wing out or slow the airplane down. This takes some time. You will have to fly and then make adjustments as you go until it is just right. An airplane that is nose heavy will be a little more docile and turn slower, while a tail-heavy airplane will tend to turn tighter but will be very pitch sensitive. If you have a radio with exponential control, use about 15% - 25% to help slow down the center and get the CG as far aft as possible. I also recommend using dual rates for landing if you have them.

Getting the racer to fly on its edge is also very easy. During a race the idea is to place the racer on about a 45 bank angle on the way down to pylon 1, and then keep it on its edge during the rest of the race only banking out if you need to make an elevation change. Since very few SP400 racers use rudder, adding weight to a wing tip can be used to level the flight. During a turn or between the pylons, if the airplane tends to climb, put a small amount of weight on the down (left) wing tip. Use a dime or larger coin if needed. I had to put two quarters on a Q40 once to get it to track straight through the turns. If the airplane tends to dive, add weight to the top (right) wing tip as needed until the airplane tracks straight down the coarse on its edge. Be careful with these little airplanes; sometime they just are not going fast enough to fly on their side.  In this case just try and fly as smooth as possible and roll out as little as possible between the turns

And of coarse, the biggest secret to a fast racer is a straight and light one.

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Recommendations

It is very difficult to improve on an airplane as sound as the Sliver. The Sliver does everything well. It launches and lands well, it flies a very smooth course and has one of the tightest turning radius’s of any of the racers out there. The Sliver in capable hands is a top performer, and it has many wins to its credit, including the NATS 2000. As a sport flyer, it is also one of the best. It has all the right proportions to fly well. The twelve pages of instructions are as detailed you will find with any kit. The only recommendation I could make for Michigan Speed Solutions would be to generate a set of drawings with the kit and pre bend the elevator control arms. I don’t have a problem getting my own wood, but I do know some sport flyers that would consider this kit incomplete without it or the hardware.

I would also like to say something about our first Sliver, the orange and black version shown with the other racers. Archie Adamisin III himself gave this Sliver to my son 2 years ago. My son put well over 100 flights on it while  hardly putting a dent on it, which shows it is a true thoroughbred. Archie is a true competitor and very dedicated racer who would help any body get involved in racing. Archie has continued his design efforts with a new design which I will be reviewing very shortly called the Vixen, produced by Matney Models.

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