Puts You in the Me 309 Cockpit. pg 54 World’s Most In-Depth RC Aircraft Magazine
Get on the Wing with the New Mini SkyFun Plus How to Cover Undercambered Wings New AT-6 SNJ Plan
Learn How This WWII Spitfire Mk IX Gives You Control With AS3X
UMX Technology Makes This ASK-21 Feel & Fly Like A Larger Model. See why! april 2013
USA & Canada $6.49
rc-sf.com
Like
@
DEPARTMENTS
Event
how to
10 12 80 81
22
42
leading edge Hot Products advertiser index Mystery airplane
Arizona Electric flight fest 2013 See how gray skies highlighted aircraft colors and pilots’ dedication. By Anthony Richards
Aerobatics part 1 Dive into the exciting world of 3D, IMAC and extreme aerobatics. By Daniel Holman
pg 42 Learn about extreme aerobatics and develop your skills with this pilot’s tips.
pg 60
This fantastic little glider matches the looks and capabilities of its full-scale cousin. BUILD
30
SpaceWalker II Wing Part 2 Frame, sheet and finish the Spacewalker II wings with these step-by-step instructions. By Jeff Troy
plan
36
6
Covering undercamber Learn the art of covering and finishing a WWI model’s undercambered wings. By Rob Caso RC SPORT FLYER — april 2013
48
North American AT-6/SNJ Dick tells you how he customized this e-powered foamy. You can too! By Dick Sarpolus
April 2013
reviews
54
hacker me 309 Enjoy the superb, stable flight of this unusual scale World War II fighter model. By Steve Rojecki
60
UMX ask-21 bnf This ultra-micro glider gives you large-scale feel, and you can fly it almost anywhere. By Wil Byers
66
powerbox igyro srs Program your fixed-wing aircraft for smooth flight with this sophisticated gyro system. By Staff
pg 54 70
pg 22
76
UMX Spitfire MK IX BNF Excellent control response and iconic good looks make this model one for your hangar. By Staff
mini skyfun rft Read why this Skyartec flying wing foamy is easy to assemble and a blast to fly. By Anthony Richards
pg 76 Follow us on twitter @rcsportflyer
RC-SF.COM
7
Flyzone P-38 Lightning Micro Warbird
Great Planes P.O. Box 9021 Champaign, IL 61821 Phone: 800-637-7660 greatplanes.com
T
he P-38 Lightning was one of the most distinctive single-seat fighters of World War II. America’s top scoring aces flew the Lightning, and now you can fly it too! Twin counter-rotating, three-blade propellers powered by a LiPo battery give this model impressive speed and handling. Because it’s a micro, the Lightning is easy to transport, easy to fly indoors or out and is a great value. Every detail has been included to make this micro just as realistic as a giant-scale warbird. The trim scheme is authentic, a molded plastic nose piece holds realistic guns and a painted pilot figure makes your plane as realistic as possible. RTFs come with everything you need to fly. The Tx-R version includes all of the great
Flyzone Tidewater EP Seaplane
Great Planes P.O. Box 9021 Champaign, IL 61821 Phone: 800-637-7660 greatplanes.com
T
he Tidewater™ makes an outstanding first float plane, offering simplicity and performance that appeal to every adventurous pilot. It assembles quickly, with no gluing required. The brushless power system provides plenty of muscle for easy takeoffs—from water, short grass or by hand—and exciting sport aerobatics. When it’s time to land, just point the plane into the wind, reduce speed and keep the wings level … it almost lands itself. For all-in-one convenience, Flyzone offers a complete, ready-to-fly (RTF) version. Or, modelers can choose the Tidewater Tx-R Prime, add their own favorite battery and charger and use any transmitter that features SLT or is compatible with Tactic AnyLink. Available mid March.
12
RC SPORT FLYER — april 2013
features of the RTF without the radio system you may already have. The Tx-R is ready to link to any SLT transmitter or any transmitter with AnyLink. Get a Micro P-38 Lightning and experience the power that won the war today. • Available in RTF and Tx-R Prime configurations. • Twin counter-rotating propellers. • Nose cone allows easy access to your battery for charging. • Factory-finished military trim scheme. • Steerable nose wheel and removable landing gear.
• Durable, factory-built AeroCell airframe screws together for fast, easy assembly without gluing. • Specially contoured fuselage, plug-in floats, and water rudder provide excellent handling while taxiing on water. • Wingtip floats are designed for superior water handling and install quickly without requiring any tools or screws. • RTF includes Tactic TTX404 2.4-GHz radio, 3S LiPo battery, charger and AA batteries
Specifications Wingspan
21 in. (535 mm)
Length
16 in. (406 mm)
Battery
3.7-V 250-mAh LiPo
Radio
4-channel w/ SLT or AnyLink (required for Tx-R)
Price
$139.99 for RTF (FLZA2310) $129.99 for Tx-R (FLZA2312)
Specifications Wingspan
41.5 in. (1055 mm)
Length
36 in. (915 mm)
Weight
30–32 oz (850–905 g)
Servos
4 micro
Price
$259.99 for RTF (FLZA3330) $169.99 for Tx-R (FLZA3332)
HOT PRODUCTS
Flyzone Tiger Moth Bipe
Great Planes P.O. Box 9021 Champaign, IL 61821 Phone: 800-637-7660 greatplanes.com
M
odeled after Geoffrey de Havilland’s DH 82 Tiger Moth, this Flyzone biplane is right at home in a backyard, at a park or even inside a gymnasium. Lots of molded-in
details, along with an authentic trim scheme and two pilot figures, add to the model’s realistic appearance. Flight characteristics are smooth and steady, with power supplied by an included ElectriFly 140-mAh LiPo battery. There are two versions to choose from—the all-in-one RTF and the transmitter-ready model that can be flown with any transmitter with SLT or one compatible with AnyLink. The RTF is available in late February, the Tx-R in late March.
Specifications Wingspan
15.1 in. (385 mm)
Length
12.9 in. (327 mm)
Weight
28–29 lb (12.7–13.2 kg)
Radio
3-channel w/ SLT or AnyLink (required for Tx-R)
Price
$99.99 for RTF (FLZA2060) $89.99 for Tx-R (FLZA2062)
• Foam construction
• • • •
Great Planes Cirrus SR-22
Great Planes P.O. Box 9021 Champaign, IL 61821 Phone: 800-637-7660 greatplanes.com
D
esigned to look and perform just like the original, this scale Cirrus SR-22 is a faithful model and a fun flyer all in one! A molded fiberglass fuselage gives the SR-22 a highly realistic and detailed look. Wing and tail surfaces are all wood assembly precovered in MonoKote® for light weight and great looks! Plus, you get to decide how you
want to fly. Install a glow engine for authentic looks and sound or a LiPo-powered electric for convenience and power. Whatever you choose, Great Planes has done the heavy lifting for you—ailerons, flaps and rudder are prehinged, the wings are removable for easy transportation and stabilizer halves can be quickly and easily installed on self-aligning tubes. With the quick and easy assembly of the Cirrus SR-22 you will get into the air quickly and easily allowing you to enjoy the great scale features sooner. The plane is finished in an authentic Cirrus trim scheme and includes running and landing lights. The Cirrus is a great aircraft with plenty of scale details and flight characteristics that will please onlookers and flyers alike. • Easy assembly
Molded-in details Authentic trim scheme Two pilot figures included ElectriFly 140-mAh LiPo flight battery included
Specifications Wingspan
69 in. (1753 mm)
Wing area
493 in.² (31.8 dm²)
Wing loading
35–39 oz/ft² (107–119 g/dm²)
Length
47.75 in. (1213 mm)
Weight
7.5–8.25 lb (3400– 3740 g)
Radio
6 channels (required)
Engine
2-stroke .46–.55 in.3 (7.5– 8.9-cc) glow engine OR Brushless electric (42-60-480 motor recommended)
Stock #
GPMA1363
• Sleek fiberglass fuselage • Wooden wing and tail structures • Large removable canopy allows easy access to radio gear and battery • Functioning navigation and landing lights • Prehinged ailerons, flaps and rudder • Accepts glow or electric engines • Machined and polished aluminum spinner Follow us on twitter @rcsportflyer
RC-SF.COM
13
BY Anthony Richards
Arizona Electric Flight Festival 2013 A Little Sun, A Little Rain; A Lot Of Fun, I’d Go Again
I
was excited to cover my first RC event, the ninth annual Arizona Electric Flight Festival (AEFF). Hosted by the Arizona Model Aviators club, AEFF is held at the Superstition Airpark east of Mesa and near the southern foothills of the Goldfield Mountains. This year’s dates fell between Thursday, January 24 and Sunday, January 27. Within the boundaries of the Usery Mountain Regional Park, Pass Mountain and
Rick Huerta’s Windrider 737-700 adds muchneeded color to the muggy skies over Mesa, AZ. Rick is a captain for Southwest Airlines.
22
RC SPORT FLYER — april 2013
the desert flora provide a beautiful backdrop for AEFF, especially when the hot Sonoran sun is out. However, when I arrived at the airpark on Saturday morning, it was far from hot and sunny.
The Event
I traveled from my hotel to the airpark with Shawn Spiker and the Hitec RCD team Saturday morning to see some pilots and airplanes
hopefully staying active despite the downpour. As we pulled into Superstition Airpark, a 3D helicopter was slicing up the air with lightningfast maneuvers—doing so for a larger crowd than we anticipated, considering the weather conditions. Once through the gate, I was impressed with the turnout for the day. From one end of the tables (covered, I should add) to the other were pilots and aircraft of just about
A very wet Senior Telemaster Plus belonging to Jim Varley takes off to show that rain can’t stop the passionate pilot from making the most of his day.
Arizona Electric Flight Festival 2013
Kyle Dahl pulls into the vertical with his outstanding Mikado Logo 700 XXtreme 3D helicopter. The mighty Scorpion 4525 520-Kv brushless motor turns the 65-in. Edge 713-mm rotors that generate tremendous power.
Ryan Archer’s Composite-ARF Extra sits on its table, waiting for the weather to lift. Under the cowl is a powerful Hacker A80-10 6000-W brushless motor that is powered by a 10S 37-V LiPo battery pack.
Follow us on twitter @rcsportflyer
When the wet weather was passing through, many of the attendees found cover, but as soon as it cleared up the airstrip came alive with people and planes again.
RC-SF.COM
23
By Jeff Troy
Sig Mfg. Co. Spacewalker II Wing, Part 2
Start Building Today — It’s Easy & Fun
1
2 These wing subassemblies were prepared in the previous installment of “Building Model Airplanes.” Check out that installment of my building series in the March 2013 issue of RC Sport Flyer.
T
he Spacewalker II is a quarterscale model of the full-scale airplane flown by the former owners of Sig Manufacturing Company in Montezuma, Iowa. The model has a wingspan of 84 in. It is designed for two- or fourstroke glow-fuel power, although my Spacewalker II will be modified to accept an electric motor power system. Constructing the Spacewalker II wing isn’t difficult. In fact, the kit is so well engineered that the top sides of the panels can be brought to completion in approximately four to six hours. I chose Bob Smith Industries (BSI) Insta-Cure+ gap-filling CA for most of the wing’s construction steps. BSI Insta-Cure thin CA and Maxi-Cure extra thick CA were used when their thinner or thicker viscosities presented an advantage. My workspace is somewhat limited, so I cut the wing plans into two sections, one for the left wing panel and one for right. The work surface is a solid-core door, over which I taped the lefthand plans, allowing enough room on both sides and in front of the plans to cut, sand or otherwise prepare the various parts for installation into the left wing
30
RC SPORT FLYER — april 2013
Cross-pinning is a technique that lets you hold parts tightly against the work surface without splitting or weakening them. Use the crosspinning method to lay down the Spacewalker II’s laminated-spruce main spar over the plans.
panel. Protect the planes with an adhesive barrier such as waxed paper, Great Planes Plan Protector, parchment paper or the clear plastic backing sheets from most aeromodeling covering films. Note that cyanoacrylate (CA) adhesives bond to waxed paper and can attach to plastic films when used too generously. So if your budget allows, parchment paper is an ideal barrier for building with CA. I chose waxed paper for its advantages of simplicity, cost and convenience. Whatever barrier you choose, now is the time to lay it over your plans and tape it down, pulling out any wrinkles to ensure that the wing panel builds flat and true. Low-tack tapes don’t stick well to waxed paper, so if it is your choice, be sure to use a good masking tape to hold it down. Framing the wing panel begins with laying the lower spruce main spar over the plans. Don’t risk splitting or weakening the spar by driving pins through it. Instead, hold the spar tightly to the work surface by cross-pinning. Cross-pinning is driving two pins into the work surface in an “X” pattern, trapping the spar or other part underneath the pins.
The ribs are installed next, and each rib should be set at 90 degrees to the work surface as it gets glued to the main spar. Use a 90-degree square. Working from right to left or left to right, install each rib. Glue them in place with gap-filling CA and a quick shot of CA accelerator. The Spacewalker kit provides a die-cut Lite-Ply dihedral gauge for setting the correct angle of the center rib. Be sure to use it so that the wing panels join at the proper dihedral angle, with no gaps anywhere between the center ribs. The upper spruce spar and balsa turbulator spar are next, followed by the upper and lower rear spars. No special instruction is needed here, but I’d bet that by now, you have come to appreciate that slight radius you’ve sanded into the spar edges where they fit into the rib notches. The edges of most balsa sheets are not straight, but rather slightly curved. This will become evident if you hold the sheet up to your eye and sight down its edge. Wide sheets must be trimmed straight with a hobby knife or sanding tools, but the Spacewalker II’s trailing edge sheet is narrow enough to be pulled into alignment as it is installed. The tails of the wing ribs don’t extend all the
Sig Mfg. Co. Spacewalker II Wing, Part 2
3
4 Poorly installed ribs cause all kinds of problems, from unequal distances between rib bays to varying airfoil depths. Help keep the wing true by using a square or triangle to ensure ribs are installed at 90 degrees to the work surface. The Sig kit’s gauge will set the root rib at its required dihedral angle.
5
Using a square or triangle when installing the trailing edge sheeting will help true the sheet and keep the trailing edge of the wing uniform. That way when you look down the length of the wing it will be straight, which means the model will fly straight and true as well. So, take a few extra minutes to put quality into your build.
6 Just stab the sheer web with your hobby knife at the correct location. Use the stab wound as the mark, then continue the slice over a Hobbico cutting mat. Trial fit the web between the ribs, then trim, if necessary, with a bar sander.
way to the trailing edge of the wing, so when you install the trailing edge top sheet, you should use a triangle to position the sheet correctly and ensure it runs straight and true. You’ll find it easiest to start at one of the middle ribs and work your way out to both sides, one rib at a time. Thin CA is a good choice for the trailer edge sheeting because it will wick into and along the joint between the sheeting and each rib. Sheer webs are more than just additional pieces that designers add to models to make them more complex. Their true purpose is to tie the upper and lower spars together, preventing them from separating—a condition that would surely cause the wing to fail. Sheer webs are usually provided slightly oversized in model kits and must be trimmed to Follow us on twitter @rcsportflyer
Use plenty of adhesive on the sheer webs; this isn’t the place for poor glue joints. Prevent smearing the glue on the sides of the ribs by using your thumb and fingers to gently bow the sheer web while fitting it between the ribs and against the upper and lower spars.
fit correctly between each bay. You could measure, mark and cut, or do it faster this way: Hold the sheer web over the bay, aligning one side of the web with a rib. Use your hobby knife and stick the tip of its blade into the web at the location of the opposite rib. Move the web, with the blade still inserted, to your cutting surface and cut the web at the knife mark. Now trial-fit the web between the ribs, trimming if necessary with a Great Planes Easy-Touch Bar Sander or ADC Tee-Bar. Glue the web to the upper and lower spars between the ribs. This is not a good place for failed glue joints, so use plenty of adhesive when installing the webs. Apply the adhesive to the face of the web where it will contact the upper and lower spars, and to the sides of the
web where they will contact the ribs. One dilemma you might encounter is preventing the adhesive from wiping off the web as it passes along the sides of the ribs during installation. The solution is easy. Just use your thumb and two fingers to put a slight bend into the web as you slip it into position between the ribs. Remove your thumb, and the web will straighten; then you can hold it tightly against the spars until the adhesive cures. The leading edge of the Spacewalker II wing is a two-piece affair. The sub-leading edge is an 1/8-in.-wide sheet that fits flat over the nose of the ribs, then after the wing’s top and bottom sheeting has been applied, the leading edge cap is glued over the sub leading edge and the whole arrangement is sanded to RC-SF.COM
31
Covering Undercamber
By Rob Caso
It’s Easy if You Follow This Step-By-Step Process
M
ost WWI aircraft employed undercambered airfoils for their wings, which provide quite a bit of lift at the expense of more drag as compared with a flat-bottomed or symmetrical airfoil. Given the horsepower limitations of the day, lift was more important, and in any case, aircraft technology was in its infancy and undercambered wings were the accepted norm. Undercambered wings present a number of challenges for scale modelers. First, there is the matter of constructing them since they are usually quite thin and there is not 36
RC SPORT FLYER — april 2013
a lot of room for internal spars, especially aft. Second, again due to their thin cross section, on all but the smallest of models, such wings must be externally braced—usually with cables—against flight and landing loads as were their full-scale counterparts. The third issue is what I will be discussing here: how to cover and finish such a wing. As an aside, I generally use birch plywood for the ribs on such models because it holds up a lot better to handling during construction and covering, which will result in a truer wing. The weight penalty is minimal, as most WWI
models have a very light wing loading. One more thing—make absolutely sure that you have installed all the hard points for strut/cable locations prior to covering because it is next to impossible to neatly fix or install these after the wings get covered. I like to use coverings that have a weave. The two that I use most are SIG® Mfg’s Koverall and Coverite™ Supershrink. Each of these products shrinks well and goes around compound curves easily, but this is where “easy” ends. Aside from the need to apply adhesive to the framework for Koverall, each of these
Covering Undercamber I used nitrate dope to seal the framework and Balsarite for the covering. Sharp cutting tools are a must.
materials is difficult to cut neatly and will generate a lot of “hairs” on cut edges. They also can shrink too aggressively, making them bridge over concave surfaces, i.e., undercamber. They can also warp or even crush thin wings rather easily. Again, this is why I like hard plywood ribs. Last, these coverings must be sealed prior to painting since they are quite porous. I start the process by making sure I am working on an ultra-clean surface and that all the frameworks have been sanded, filled and primped over. Covering does not hide a bad building job.
Here’s my step-bystep:
If the model is going to have a lightly colored final scheme, I first apply a light wood stain to the airframe to prevent the balsa color from showing through the finish. Then I lightly sand the surfaces that will touch the covering. Next you will apply a couple of coats of nitrate dope, reduced about 40%. Nitrate will raise the grain of the wood, so re-sand the structure and apply two coats of covering adhesive (I use Balsarite® or StixIt®) reduced to cream consistency. Balsarite can be reduced with nitrate thinner—there are also water-based adhesives available, but I have not used them. Check the airplane’s structures one last time. Are all the hinge slots and cable hard points installed, have provisions been made for control horns and do the outlines of the surfaces match up? For wings having a straight leading edge (LE), I use a single piece of covering for each wing panel. Doing so eliminates a cutting seam. So cut a piece large enough to wrap around the LE to cover the upper side of the panel. Again, the goal is to keep the covering from Here the covering has been applied using the process described in the text—properly applied covering will allow the framework to show through. Follow us on twitter @rcsportflyer
1 Cut a piece of cloth big enough to do the entire wing, top and bottom and make sure the work area is clean.
2
3 RC-SF.COM
37
BY Daniel Holman
Aerobatics (part 1)
Even more difficult than 3D aerobatics, extreme aerobatic (XA) flying is full of heartstopping, low and fast maneuvers such as this high-speed slow roll. In this picture, I am flying my model at approximately 100 mph right down the runway, but not far off the pavement, which adds to the excitement for spectators.
H
ow many of us enjoy experimenting with the laws of physics, trying to find a loophole in these limits, trying to raise the bar or simply trying to disprove a law? I enjoy many aspects of physics and find it very exciting to apply these laws to this awesome sport! The mathematical formulations that govern aerodynamics are here to stay, but with the amazing advancements in airframes and equipment that we now have access to, we can push our flying to the edge of possibility and ride the red line of the laws of physics with extreme aerobatic flying! In the next few issues of RC Sport Flyer magazine, I will take you through the process of getting into aerobatic flying, starting from the beginning and going well into the advanced forms of competition aerobatics. For me, this is the most exciting part of our hobby of remote-controlled (RC) 42
RC SPORT FLYER — april 2013
Extreme aerobatic flying includes lots of fast rolling where the pilot controls the airplane’s flight path while it is rolling at over 700 degrees per second! That is Mount Adams in Washington State in the background in case you were wondering.
Hovering with smoke on is always a crowd pleaser. Along the journey of practicing 3D aerobatic flight, you will learn to completely control the airplane in fully stalled conditions.
For some pilots, this situation looks about as bad as they come. In 3D and XA flight, these orientations are very common, and I had my Extreme Flight® MXS EXP back into inverted flight by the time it was 2 ft off the runway.
Aerobatics (part 1)
The knife-edge spin is an aggressive maneuver in which the airplane rotates gyroscopically around the wing tube—the airplane’s center of gravity position—while plummeting straight down to earth. Throw in some smoke and it makes for a very impressive aerobatic maneuver that you should add to almost any competition routine. The smoke really provides a nice reference point in the air for the spectators too.
aviation, and I am excited to share my experience and knowledge with you! The first thing I would like to cover is defining the different forms of aerobatics and explaining how they all work together.
maneuvers include hovering, torque rolling, harriers (upright, inverted or rolling), flat spins, waterfalls and the like.
3D
The form of aerobatics that goes back the furthest in RC aviation is pattern flying. This type of aerobatics, consisting of point rolls, snap rolls, loops with integrated point rolls, split-S turns, stall turns, slow rolls and similar maneuvers, is flown in a “box” and is judged for precision in the maneuvers as well as placement and symmetry. In pattern contests, all contestants in each class fly the same prescribed routines. These routines change every year but lay a solid and even playing field for all participating pilots. IMAC (International Miniature Aerobatic Club) competition flying is similar to pattern in many ways, but it requires that all airplanes used in classes above basic must be replicas of full-scale airplanes. Competition pattern airplanes, however, are not limited in their design. IMAC competitions also use slightly different sequences and rules
Probably the most well-known form of aerobatics today is 3D. Three-dimensional flying has become very popular over the last decade, but it was officially introduced by Quique Somenzini back in 1994. Until then, competition freestyle aerobatics were, for the most part, limited to scale aerobatics similar to those you are likely to see at a full-scale air show. As engines and servos became more powerful, pilots began to enlarge the control surfaces of their airplanes, and following in Quique’s footsteps, began to fly maneuvers that required the propeller rather than the wings to lift the airplane. The definition of 3D that I believe to be the most accurate is “flying beyond the point of stall.” A common misconception is that all crazy aerobatic flying is 3D. When the airplane is being controlled in a fully stalled attitude, that is 3D. 3D Follow us on twitter @rcsportflyer
Precision aerobatics (IMAC and pattern)
High-alpha knife-edge flight is considered 3D because the surfaces are, for the most part, stalled. In these types of aerobatics, we like to bring it all the way down to the deck as I am here with the Hangar 9® 3.1-m Sukhoi 26MM!
and closely emulate the full-scale IAC (International Aerobatic Club) competition flying. I will go into more detail about IMAC later in this series. I believe strongly that precision aerobatic flying is the best way to improve your flying skills. No matter what your primary interest is in this hobby, precision aerobatics will help your flying as it teaches you to truly control the airplane’s flight path and put it where you want it. In this series, we will also go through learning to completely control an airplane close to and beyond the point of stall. Skills in this area have the potential of saving many airplanes in bad situations and are very valuable!
EXtreme Aerobatics (XA)
As with all extreme sports, RC aerobatic flying has evolved greatly, especially over the past decade. With airframe manufacturers using new and advanced building techniques, some of the aerobatic airframes that we now have are able to withstand up to 20 g-forces. (G = force of gravity.) These extremely strong airframes, coupled with the latest RC-SF.COM
43
BY Dick Sarpolus
NORTH AMERICAN AT-6/SNJ These Give You a Profile on How to Have Fun!
S
heet foam profiles are one of the standard airframe construction methods used by today’s electric-powered airplane modelers. They can be built super lightweight for fantastic 3D performance. They can also be built quickly and easily by scratch builders working from magazine plans. Doing so gives modelers more choices in the models they build, and the sheet foam is a very low-cost way for any who want to experiment with wild and crazy designs of their own. For those liking scale models, built to the right outlines and with some amount of scale trimming, the foam profiles can look surprisingly realistic. For this model, I made a change to the usual all-sheet-foam airframes— rather than the flat plate wing, I prefer to build my models with a hot-wire cut foam wing that yields a thick, fully symmetrical airfoil. It’s
Dick Sarpolus flies his custom AT-6 Texan electric foamy with ease. You will be pleased with how well this airplane flies once you toss it into the air.
a hybrid—sheet foam for the profile fuselage and tail surfaces, along with a hot-wire cut foam wing core. The added weight doesn’t bother the model’s performance, and I find it can handle windy weather better. I also think it has a larger airplane “feel” for the pilot. The hotwire cut foam cores add a little to the expense, but this method is still a low-cost building technique. If you can’t cut the foam cores yourself, they are commercially available, or anybody you know with a foam cutter could make them. I picked the AT-6/SNJ aircraft to model because it’s an interesting Here are the airframe components cut and ready to be put together. Note the thin sheet foam fuselage and tail surfaces below the hot wire cut foam wings.
48
RC SPORT FLYER — april 2013
NORTH AMERICAN AT-6/SNJ airplane, there are so many of them still around and there are lots of interesting color and trim schemes to select from for that scale appearance. North American Aircraft started development on their NA-16 in 1934, and over the next few years, numerous changes resulted in The rudder is controlled by a cable pushrod to a the AT-6 by 1938. The plywood control horn. The cable is threaded through Navy designation for a tube mounted to the fuselage to prevent bending. this aircraft was the SNJ. Between the time production started and ended in good epoxy adhesion. The two 1944, around 15,000 aircraft were wing panels butt up to the sides built. Many other countries bought of the fuselage, with the 1/8-in. this aircraft for training and/or fighter plywood wing joiner epoxied use. I like the pre-war Navy color into the wing panels between scheme of a white fuselage, yellow the wing spars. This way, a large wings and red tail surfaces, along with hole doesn’t have to be cut the pre-war insignia for its colorful through the fuselage for the wing. appearance. It is easy to do and makes for a This foam job is pretty rugged stronger fuselage. A source for with its plywood nose doublers the hot-wire cut foam wing cores and thick wing; it will take some is The Core House at home. mishandling, and it’s easily repaired. earthlink.net/~philcartier. They To complete the model, I needed a have a deal on these cores—a brushless outrunner motor, the right box of four sets at a good price. electronic speed controller (ESC), a The cut foam wing panels three-cell LiPo battery pack, three could be left bare, but any small servos and a small receiver. lightweight, low-temperature I like to get two copies of the plastic film will keep them clean plans so I can cut one copy for the paper patterns of the sheet foam and plywood parts. A metal straightedge and a scalpel-type hobby knife are used to cut out the sheet foam parts. A scroll saw or band saw helps with the plywood parts. Those plywood doublers on the nose strengthen the fuselage and are well worth the added weight. I usually use five-minute epoxy as my glue of choice because I like to get projects done quickly. When gluing the carbon fiber tube to the upper and lower fuselage pieces, sand the tube well, scuffing it up with sandpaper so the epoxy sticks well to it. You could use a hardwood strip, but the composite tube is a lot stronger. Epoxy sticks well to most of the sheet foam materials, but on the ones with a thin plastic skin over the foam, I poke a bunch of small holes through the skin to be sure to get Follow us on twitter @rcsportflyer
The elevator is actuated by a cable locked into another plywood control horn. Note the tape above it that is used as a hinge for the rudder.
The ailerons are operated by a single servo mounted into the bottom of the wing with hot glue. The pushrods can be made from either .032 or .047 wire. It does not take much to get this foamy in the air. Thanks to its lightweight design and brushless motor, it only needs a quick toss to get airborne.
RC-SF.COM
49
BY Steve Rojecki
Hacker Me 309 The Highest-Performance Light Sport Plane is Now Yours
Out of the box, the Hacker Me 309 looks awesome. The construction is top notch, and the finish is a very well-done, flat camouflage scheme. Other than adding decals and a few scale parts, the plane’s exterior is finished. The Me 309 comes with pockets built into the trailing edge for hinge-point-style hinges. Make sure to use a little lubricant on the hinge pin area to prevent the epoxy from sticking.
54
RC SPORT FLYER — april 2013
Hacker Me 309 Tail servos are mounted directly in the stabilator. This makes for short, stiff linkages for precise control and minimizes the chances of flutter. I glued in two small blocks of hardwood to screw the servo down to.
The large forward fuselage hatch provides easy access to all the components in the fuselage. The hatch removes easily with a pushpin latch at the rear of the hatch.
W
hile walking the isles of the 2012 Toledo Model Expo, I visited the Hacker/ AeroModel booth. They were debuting an unusual World War II fighter aircraft model, the Me 309. The ME-109 was well known during the war, but the Me 309 was only produced as a prototype. It was designed by Willy Messerschmitt. Four examples were manufactured by the Messerschmitt company for a flight test program that was conducted in 1941. The Me 309 had several unusual features for its day, such as tricycle landing gear for improved ground handling. It also had a pressurized cockpit for more comfortable and effective highaltitude performance. The Me 309 was a definite improvement over the ME-109—it was 40 mph faster and outclimbed its predecessor. However, the performance was
not better than the already-inproduction FW-190. As a result of the disappointing performance, the German High Command decided to put all the production efforts into the FW-190 and canceled the Me 309’s test program with just the four prototypes built. The scale model of the Me 309 was the result of a Hacker motor employee’s desire for an unusual scale World War II model. He spent countless hours researching the airplane and then scratch-building a prototype. After the prototype flew and Rainer Hacker (Hacker Motors’ owner) observed the excellent performance, Mr. Hacker decided to produce an ARF version of the Me 309. As a longtime modeler (over 40 years), I’m always on the watch for new and unusual airplanes to add to my fleet. The Me 309 fit the bill to a
tee. I struck a deal with the importer (Hacker/Aero-Model) to write a review and also show the model off at various fly-ins. I really like the fact it was designed to be electric powered. This makes easy work for the power system install and setup, as it does for the rest of the ARF’s assembly. My model was shipped just a few weeks after Toledo, but as with some projects, its assembly and flight testing were a bit delayed. No matter, it is a superb flyer, and here is what I found in terms of the build and its flight.
What You Get
The model arrived in an extremely sturdy shipping container. The box was made from 1/2-in.-thick corrugated cardboard. So, even with a few scuff marks on the outside of the box, the inners of the box were in
To prevent the nose wheel steering cables from tangling in the nose strut or wheel well area, I slip in a large cable tie in a “U” shape and attach it to the steering cables using heat shrink tubing.
Follow us on twitter @rcsportflyer
RC-SF.COM
55
BY Wil Byers
UMX™ ASK-21 BNF
From tip to tail the E-flite® UMX ASK-21 looks like the full-scale glider. The bubbled canopy and nose flow the fuselage into the scale tail boom just as they should, providing convincing realism when airborne.
A UMX Scale Glider With Big-Scale Flight Feel
D
esigned by Rudolf Kaiser to replace the ASK 13, the Schleicher ASK 21 was designed to provide a modern tandem two-seat glider that would fit the needs of pilots who were between initial training and singleseat performance sailplanes. Though it is used mostly for training, the ASK 21 is also capable of crosscountry soaring as well as aerobatic instruction. Consequently, it has found a huge following in the soaring community.
The fantastic ultra-micro ASK-21 model glider matches the looks and training capabilities of its full-scale cousin. With little assembly required, it is a very attractive model for scale enthusiasts. When you consider that it comes with a release mechanism for aerotowing it behind the E-flite UMX Carbon Cub, you’ll find that this glider is a nearly perfect pick for pilots who want a change of pace from their large-scale gliders. Moreover, the UMX ASK-21 is slope soarable in light winds, and it will
thermal in the smallest bumble rising from your airfield.
The Kit
The E-Flite® UMX™ ASK-21 Bind-N-Fly (BNF) comes in a sturdy, corrugated cardboard box that is reinforced with a foam insert. The box is designed to double as a carrying case. It comes with all the parts and pieces you’ll need to get your glider flying. Our review model arrived without any damage because of this great carrying case/box. The fuselage comes preassembled, built with a durable and lightweight foam bottom and hard plastic top. Carbon pushrods and ultra-micro, linear long-throw control servos keep this glider as lightweight as possible. Note too that this is a fullhouse glider with ailerons, elevator and rudder controls. There is no pilot included, however. The E-flite UMX ASK-21 comes with the hardware needed to install the wing, a 1S 3.7-V 150-mAh Lithium Polymer (LiPo) battery, a single-cell
Good looks are just one part of the E-flite®UMX ASK-21 BNF package that makes it a terrific buy. It also soars incredibly well.
60
RC SPORT FLYER — april 2013
E-Flite® UMX™ ASK-21 BNF
Featuring a 33.9-in. wingspan and only weighing 2.56 oz, the UMX E-flite ASK-21 is small, but it will feel like a much larger aircraft once in the air.
LiPo charger, AA batteries for the charger and the accessories needed for aerotow and high-start launches.
What You Get
• Airframe Fuselage, wings, canopy • Servos (2) Spektrum 2.3 g performance linear long throw • Receiver DSM2/DSMX AS3X receiver • Battery E-Flite 1S 3.7-V 150-mAh 25C LiPo • Accessories High-start hook/stake/cord, tow plate/line
Needed To Complete • Transmitter Spektrum DX18 2.4 GHz
The UMX ASK-21 arrives in an attractive box that has all you need to know about owning it printed on the front. The ASK-21 fits neatly inside its box.
In Flight
When I tell you that the E-flite UMX ASK-21 has large-scale glider feel, I’m not kidding. Those who know me are aware that I fly large-scale gliders and have a passion for them. Well, this little glider—with its AS3X control—has a much larger control feel than its 33.9-in. wingspan and 2.56-oz weight indicate. Now listen, this is not to say that you’re going to be able to fly this model in 20-mph winds or tow it behind your 1/4-scale Super Cub. It will, however, give you literally hours of soaring enjoyment when you fly it at a slope site in light winds of 5–10 mph. I’d add that this glider will open up slope soaring sites that you had never dreamed of flying before. So, if you have a 20-ft high bluff near your home, you now have the perfect fit for getting in some
In the kit, you get the assembled fuselage and wing plus a 3.7-V LiPo battery, 1S DC LiPo charger, four AA batteries and aerotowing and high-start equipment.
Follow us on twitter @rcsportflyer
The smooth and streamlined design of the Schleicher ASK-21 glider is reflected in this scale ultra-micro glider. The scale canopy even includes cutouts for the air vents in its side.
The receiver board and rudder and elevator servos can be seen nestled inside the fuselage. The aileron servo sits atop the center of the wing. Below the receiver board is the servo that actuates the aerotow release. RC-SF.COM
61
BY RC-SF Staff
PowerBox Systems iGyro SRS
®
Say Hello to Stable Flight With a State-of-the-Art Gyro
W
hen flying any aircraft, wind and aerodynamic influences can cause it to stray from straight and level flight without any input from you, the pilot. Weather is an unpredictable thing, and even on clear days there can be small breezes that knock your aircraft around in flight. However, you can now combat these adverse effects with the installation of the iGyro system, which is sold by PowerBox Systems®. Also, the power of iGyro is delivered for 3D flying and for sport flying. Simply put, it will help you fly your airplane more smoothly than ever before.
Features
With components housed in a strong, aluminum case, the PowerBox Systems iGyro SRS uses a special regulatory algorithm that was written specifically for controlling fixedwing aircraft. It utilizes a GPS sensor
Our iGyro unit arrived from Germany safe and sound, thanks to the sturdy cardboard box and careful packaging that protected it.
and an accurate triple-axis microelectromechanical system (MEMS) sensor to provide excellent stability. The iGyro has a simple, easy-tounderstand user interface that lets you program it for all your airplane’s controls. iGyro use the new servo bus technology, and it features seven ports to simplify the wiring and hook-up of the gyro for Futaba S-Bus, Jeti, M-Link, HoTT and Spektrum DSMX/DSM2 systems. The unit utilizes a state-of-theart 16-bit micro-processor that ensures proper control responses are processed and then distributed at super-fast bus speeds. A 128 x 64-pixel OLED (organic light-emitting diode) screen presents crisp and clear readouts to make adjustments easy to see. The gyro settings are Inside the box are the iGyro unit and its USB interface cable, SensorSwitch, GPS sensor, uni patch-leads and self-adhesive pads.
66
RC SPORT FLYER — april 2013
PowerBox Systems® iGyro SRS
The SensorSwitch is the control module used to program settings and navigate the iGyro’s menus. You will use it to set up and adjust your iGyro.
changed with a SensorSwitch. The SensorSwitch features three navigation buttons. The SET button is used to select menus and confirm value entries, while the I and II buttons navigate menus and alter values accordingly. The GPS Sensor uses the aircraft’s airspeed data to provide the gyro with gain adjustments twice a second for nearly constant gain acclimation.
For those familiar with many other gyros, the gains are typically fixed at lower rates and have better use at slower speeds than higher speeds. With the GPS sensor regulating the gyro gain, the unit always has the desired effect over your airplane’s control surfaces no matter how fast or slow the aircraft is traveling. Another exceptional feature of iGyro is the unique ability to
place the system anywhere in the aircraft. Yet, you only program it as to what its orientation is relative to its position in the aircraft. Other GPS units require you to program in X, Y and Z coordinates from the aircraft’s center of gravity (CG), but not the iGyro. You simply enter the direction of the OLED screen and sensor switch relative to the aircraft’s orientation. You do it by selecting UP/ DOWN, LEFT/RIGHT or FRONT/ BACK. For instance, if the screen is installed facing up and the sensor facing the wings, the GPS orientation would be programmed as “Screen: UP” and “Switch: LEFT/RIGHT.” For use in delta wings, the gyro supports delta mixing for elevon controls. Simply enable Delta-Wing at the General Settings menu. The gyro will analyze the aileron and elevator inputs from the transmitter and the deviation values from the sensors to generate an output for both control surfaces. The mixing values for the elevons under the delta-wing configuration are under ELEVATOR-A and AILERON-A. For models featuring canards or vector controls, the ELEVATOR-B output can be set up independently. Aerobatic pilots pay attention, because the iGyro makes use of three flight modes to allow the pilot better control during certain flight maneuvers. Flight Mode 1 completely disables the gyro, with the exception of the Delta mixer if the aircraft has a delta wing, while Flight Modes 2 and 3 are customizable to either enable or disable Heading values for normal and aerobatic flight. The flight mode can be toggled in flight when programmed for a three-position switch.
The right side features three black input sockets for the GPS unit and the receiver, and three white Spektrum® satellite sockets.
The left side houses the servo ports. The two far right ports are for the aileron servos, the next two for the elevator servos and the last for the rudder.
Follow us on twitter @rcsportflyer
RC-SF.COM
67
BY RC-SF Staff
UMX Spitfire Mk IX BNF Engage the Enemy With This World War II Fighter
P
This fantastic ultra-micro warbird fighter is scaled after the planes the brave RAF pilots used over the Cliffs of Dover during the Battle of Britain.
The removable landing gear adds more realism to the scale appearances in flight for this stunning Spitfire. Note the panel lines, authentic markings and twin radiators that give it that fullscale look. This ultra-micro Spitfire hardly sacrifices any details from the full-scale aircraft. It still carries the twin Hispano cannons and even a fourblade propeller, which add to the realism.
70
RC SPORT FLYER — april 2013
erhaps one of the most iconic fighter aircraft of all time, the Supermarine Spitfire served with many of the world’s air forces but found fame with the Royal Air Force (RAF). First produced in 1938, the Spitfire helped fight back the Nazi German Luftwaffe during the Battle of Britain and throughout World War II. Though the Hawker Hurricane shouldered much more of the battle, the public viewed the faster, ellipticalwinged Spitfire as the RAF fighter. In 1942 the Spitfire had a superior enemy to fight, as the Focke-Wulf FW-190 had air supremacy. The British needed to respond quickly to
ParkZone® UMX Spitfire Mk IX BNF BNF
ParkZone® designed a very attractive and informative box that gives you a perfect carrying case to transport your UMX Spitfire Mk IX from home to airfield/indoor site safely.
Inside the sturdy box, you will find a completely assembled Spitfire, a single-cell DC LiPo battery charger, a 3.7-V 150mAh LiPo battery and four AA batteries that you’ll use in the charger—it’s all there.
The four-blade propeller looks even better up close. This image also shows off the accurate Hispano Mk II cannons and the Merlin engine exhaust stacks. Check out the scale accuracy of this model.
the threat and modified existing Mk VC Spitfires to Mk IVs by upgrading their early Rolls-Royce V12 Merlin 45 engines with the improved Merlin 61s. The Mk IX had an outstanding climb and high-altitude performance that gave it the necessary edge to compete with the brawny FW-190. Although you likely won’t be encountering any Butcher Birds over your backyard, this ultra-micro fighter legend is just as attractive as its full-scale inspiration. It is just as agile and powerful too, with its fourblade propeller pulling it through the air. Follow us on twitter @rcsportflyer
The Kit
The ParkZone® UMX Spitfire Mk IX Bind-N-Fly (BNF) sets itself apart from the other ultra-micro warbirds as the first to feature the incredible AS3X stabilizing system. Built into its DSM2/DSMX six-channel receiver/ESC board, the AS3X gyro counters most light winds and other environmental effects that might otherwise make this little airplane difficult to control. However, builtin AS3X means ultra-smooth flight performance indoors and out. The aircraft comes shipped in a cardboard box that doubles well as
a carrying case, so you can transport the aircraft and its accessories to and from the airfield/indoor venue without worrying about damaging your model. Inside the case is a foam insert that protects the model and all the included items from shifting during transit. Note that your Spitfire will come assembled and ready for flight. A 1S 3.7-V 150-mAh LithiumPolymer (LiPo) battery, 1S charger and four AA batteries to power the charger are included as well. All you need is a Spektrum® 2.4-GHz DSM2/ DSMX transmitter to control your UMX Spitfire, and it will be ready to go airborne.
What You Get
• Airframe Fuselage, wings, empennage, removable landing gear (prebuilt) • Motor ParkZone® Ultra Micro coreless • Propeller E-Flite®100x100-mm four-blade RC-SF.COM
71
BY Anthony Richards
Hobby People Mini Skyfun RTF A Seriously Fun-to-Fly Electric-Powered Wing
If there is one thing this aircraft wants, it is altitude. It can climb and keep on climbing like there is no tomorrow.
F
lying wing aircraft are unique in the full-scale world. Most notable in today’s military fleet is the B2 Stealth Bomber. The Northrop YB-49 made history, however, and its demise saddened many aviation enthusiasts. Other flying wings include the Waterman Aeromobile and of The canopy is attached to a hinge at its front that lets course the array of it rotate upward and open to reveal the electronics hang gliders that made beneath. aviation affordable to the masses starting in the early 1970s. You will waste no time getting your Skyartec Mini SkyFun readyto-fly (RTF) flying wing assembled and in the air. You can easily take it to the sky the same day you bring it home from the hobby shop. Featuring
A Skyartec 2S 7.4-V 900-mAh 15C LiPo battery powers the Mini Skyfun through basic turns and rolls as well as fast flybys.
The Skyartec Mini Skyfun has plenty power and speed. It gets it from its Skyartec BL250, 4500-Kv brushless motor and GWS 4.5 x 3 propeller.
76
RC SPORT FLYER — april 2013
Hobby People Mini Skyfun RTF
The aircraft flew well from this butte in Eastern Washington. The controls responded well to the inputs with plenty of authority. The kit includes almost everything you need to get your Mini Skyfun flying in about an hour. All you need are four AA batteries for the transmitter.
a brushless outrunner motor and a three-axis gyro, this little foamy has exciting performance that is matched with control stability. The Mini Skyfun from Skyartec will give you high- and low-speed flight performance that is absolutely crazy fun no matter how you slice it.
The Kit
What you Get
• Airframe Fuselage, wings, vertical stabilizers • Motor Skyartec BL250, 4500 Kv • Propeller GWS 4.5x3 • Servos (2) Skyatrec VTS-028 3.7 g • Receiver Skyatrec AP301/3G3X 3-axis gyro • Transmitter Skyatrec SKY-G02 2.4 GHz • Battery Skyartec 2S 7.4-V 900-mAh 20C LiPo
The Skyartec Mini Skyfun ReadyTo-Fly (RTF) kit arrives in a twopiece cardboard box with one piece as an open-ended covering and the other a slide-out box. Inside, the fuselage is held down with thick paper box inserts that keep the airframe from sliding around and being damaged during shipping. A larger paper box contains the twin vertical stabilizers, part A and B epoxy, a 2S 7.4-V 900-mAh Lithium Polymer (LiPo) battery and a LiPo charger. Another box contains the SKY-G02 Mini LCD transmitter, which is a conventional two-stick Two small plastic control horns bridged by a wire system designed for linkage arm join to control the elevons along the Mode 2 control. trailing edges of the wings. Follow us on twitter @rcsportflyer
• Charger Skyartec 2–3 cell LiIo/LiPo • Hardware Propeller Two-part five-minute epoxy 12-V AC-DC power supply
Needed To Complete • Batteries (4) AA for charger
In Flight
Let me start by saying this little flying wing foamy airplane is just a blast to fly. When you hit the throttle it is going up. I mean it! The powerto-weight ratio of this airplane is superb. So, when you give it a launch and throttle up it is going to head for the sky. On my first flight I found that I had the center of gravity a bit too far back, so the model wants to climb even with full down-trim control. So, I landed it and moved the battery forward about a quarter inch. That
The micro servos come preinstalled in recesses in the wing where they can be kept safe during belly landings. RC-SF.COM
77