 |
|
 |
|
|
|
|
          |
            |
 |
This item is discontinued. GREAT PLANES AT-6 TEXAN ARF 40 MONOKOTE 
SPECIFICATIONS Comments: nice scale detail, solid construction and delightful flight performance, all in an easy-to-assemble package. This plane flies like a sport model while maintaining many of the scale details of the original Texan. Hits
Misses
The AT-6 Texan has been a favorite subject of experienced modelers for many years because of its classic lines and historic significance. Thanks to Great Planes, everyone can now experience the excitement of this famous warbird in an easy-to-build .40-size ARF. Almost 60 years ago, the Texan was used to train the young pilots who fought in the skies over Europe and the Pacific. The Great Planes Legendary Warbirds series AT-6 .40 ARF will have a new generation of pilots flying this classic plane and enjoying the many scale details, the acrobatic yet forgiving flight performance and the easy construction that a state- of-the-art ARF can provide. The AT-6 kit is complete right out of the box. The construction is almost entirely wood, and the plane is covered in colorful MonoKote. The fiberglass cowl and all of the ABS parts have been painted. Fixed landing gear is included, and the Texan has been designed to accept Hobbico retracts (part no. HCAP4010). The kit comes with all necessary hardware except what is required for the retracts. The instruction manual is well-illustrated and has many helpful hints. WING ASSEMBLY The first step is to remove the covering from the aileron servo openings on the bottom of the wing. Great Planes has installed a temporary pull-string you can use to pull the servo extension wire through the wing panel; there is also a string in the wing's center section. Join the outer wing panels on each side of the center section by using a pair of the hardwood wing joiners that come with the kit. The two pairs of joiners—one for each side—are preset at the proper dihedral. Test-fit the wing panels a few times to ensure proper fit; then epoxy them. Remove any excess epoxy with alcohol and a paper towel. After the wing epoxy has cured, fit it to the fuselage and align it with the tail post. Then, fasten it to the fuselage using the bolts included in the kit. The wing's bottom has open bays for the aileron servos. Fasten the servos to the servo-bay cover plates and then mount the covers in the bays with four screws. The kit comes with fixed, bent-wire landing gear but is designed to accept optional Hobbico mechanical retracts. The wheel wells and mounting rails are already installed, so I opted for the retractable gear (see "To Retract or Not to Retract," below). TO RETRACT OR NOT TO RETRACT For the most part, retract linkage setup on the Texan is fairly simple. Bending the struts so the wheels retract fully into the wells without binding on their sides, however, does take a bit of patience—so, be patient. The gear strut has to be bent to a pattern illustrated in the instruction manual. A pair of vacuumed-formed wheel wells is included with the Texan. Install them by first removing the covering over the wheel-well cutout in the bottom of the wing and then gluing the wheel well into place with a little medium CA. Keep in mind that you have a right and a left well. With the gear installed and the retract servo in place, you can make the adjustments to the pushrods for the proper clearance and operation. Remember, it's very important that the gear lock in both the up and down positions without stalling the servo. Once you are satisfied with the installation, you can glue the ABS center-section cover into place. Although Hobbico's mechanical retract units function quite well, and they do fully lock in both retracted and deployed positions, I recommend you forgo retracts altogether and opt for the fixed gear if you fly off a grass field that is even a bit on the rough side. It's not that the retract unit can't take a bit of a beating; it can, and it never gave me any problems. It's simply that if the gear struts get bent even slightly, the wheels will not line up in the wells properly, and this will prevent full retraction. If, on the other hand, you fly off pavement or well-groomed grass, by all means, go for the retracts. TAIL ASSEMBLY The fuselage's rear comes notched for both the vertical fin and the stabilizer. After removing the covering on the fuse, stab and fin, align them with the wing and epoxy them in place. After the stab and fin have cured, fit the rudder, the elevators and the tailwheel assembly. The pushrods come installed and ready to attach to the servos. THE FUSELAGE The instruction manual includes a template for the engine mount. I chose an O.S. .70 Surpass 4-stroke to power my Texan, but any .40 to .51 2-stroke or .48 to .80 4-stroke will do. The firewall is recessed just behind the front of the forward section's outer ring of the fuse. Use four 6-32 bolts and blind nuts to bolt the adjustable engine mount to the firewall. When you mount the engine, allow 4 1/2 inches from the back of the engine mount to the engine's thrust plate for proper cowl clearance. I used four 6-32 socket-head bolts and lock- nuts to hold the engine in the mount instead of the four sheet-metal screws included in the kit. Holes are marked for the throttle pushrod, but remember to roughen the outside of the pushrod to give the glue some texture to bond to. Medium CA works well here. Epoxy four hardwood blocks to the fuselage's front ring, and mount the cowl on the blocks. RADIO INSTALLATION Mount throttle, rudder and elevator servos in the fuselage. The elevator servo drives two pushrods—one for each elevator—and the instruction manual shows a simple way to do this. The receiver and battery pack are just forward of the servos. I added a Great Planes switch mount and charge jack (GPMM1000). The wing contains two or three servos, depending on whether you use the optional retracts, and Great Planes has provided all the hardware for the radio installation, as well as pushrods, clevises and control horns. The most important part of the aileron servo installation is to ensure a good glue bond on the blocks that are mounted to the servo hatch covers. The pull-strings for the aileron-servo extension wires really help with this step. All the control surfaces use CA hinges, and you need to be careful with them. Great Planes recommends that you have 1/64 inch of clearance between the trailing surface and the control surface. This allows the proper movement without binding at the hinge joint. The O.S. .70 Surpass is at the top of the suggested power range for the Texan. Swinging an APC 13x6 prop, after some break-in, it flies the model with authority. In classic O.S. style, the .70 ran virtually right out of the box, idling at 2,500rpm almost immediately. The Texan would be adaquately powered with any .60- size 4-stroke, and even a broken-in Saito .56, a very powerful engine for its size, would be a good choice for scale-like warbird flight. Of course, any .40- to .50-size 2-stroke would also do the job for this model. FLIGHT PACK Hobbico's Command servos were used throughout the Texan, and they seemed to have quality on a par with other name-brand radio equipment, at a very good price. Two CS-59 low-profile ball-bearing aileron servos (with a transit speed of 0.10 sec. and 61.1 oz.-in. of torque at 4.8 volts) were used for roll control; three CS-55 deluxe standard servos were used for rudder, elevator and throttle. A CS-63 low-profile ball-bearing retract servo (not shown) was used for the gear. Hobbico's Command CR-7 dual-conversion 7-channel FM receiver was also used. All Command equipment functioned perfectly during the flight testing, photo sessions and subsequent flights with the Texan. FINISHING The Great Planes AT-6 kit comes with ABS wingtips that are attached using medium CA. Check the clearance for the aileron tip before final gluing; some trimming may be required. Not so for the cockpit; it's a perfect fit. Use a few small screws to fasten it securely, or you can glue it if you prefer a permanent installation. The generous supply of decals included in the kit adds the final touch to your AT-6. Once decorated to your satisfaction and with all of the equipment installed, including the prop and battery, it's time to balance the Texan. My CG machine makes this final step a breeze. CONCLUSION The Great Planes AT-6 Texan is a perfect example of what makes ARFs so popular these days. The scale details are impressive, the construction quality is excellent, the assembly is fast and trouble-free, and the flight characteristics are on a par with many sport planes. The Texan is a highly admired, classic warbird; the Great Planes .40-size rendition is destined to develop just as favorable a reputation among modelers. FLIGHT PERFORMANCE I don't know about you, but for me, the in-flight visibility factor of a model is a big part of how easy—or difficult—it is to fly. With its yellow wings and red markings, the AT-6 is a very easy model to keep tabs on in flight. Loss of orientation when flying military aircraft that are often finished in varying combinations of olive drab, tan, dark blue, sky blue and dove-gray can be a visibility problem for many. This is not the case with the Texan, since Great Planes chose the bright scheme of an Army Air Corps trainer. DOWN TO BUSINESS OK; visibility aside, how does it fly? With its high aspect ratio wing and sport-plane airfoil—very nicely. Even on the first flight, after minor down- and left-aileron trim, I immediately felt secure enough with the characteristics of the Texan to deliver close-in and slow passes for Walter's Nikon. That doesn't mean, however, that you can slow this one up like a fun-flyer; you can't. The wing will stall, but only at very low speeds; much lower than would seem appropriate for a warbird, even an advanced trainer-type warbird. The thing I liked most about the Texan is that it doesn't need any in-flight trim-setting changes from low speed to flat out. Some designs, for example, need elevator trim changes from high-speed to landing-speed transition. There's nothing wrong with that; it's just the way some designs are. I love it, however, when a model tracks the same at all throttle settings, and that's what the Texan does. This doesn't, of course, include gear-up and gear-down elevator trim changes. With the gear tucked away, every retract-equipped model I've ever flown needs down trim, and this one is no exception. Conversely, up-elevator trim is needed when the gear's parasitic drag is reintroduced into the airstream. All basic aerobatics are possible with this model; however, maneuvers requiring top rudder would be a stretch. I tried a knife-edge and it was, at best, a dubious undertaking. Anyway, that's not what a Texan does. Smooth flying and, with that high aspect ratio wing, gracefulness on the roll axis is what a Texan is all about. Rolls were very positive, albeit slightly barreled. Stall-maneuver recovery is quick, and the Texan gets right back on heading very quickly and tracks through the sky in bright-colored beauty. It's a very enjoyable model to fly. The Surpass .70 is about as much power as you'd want to put in this model. It's not over-powered but it is at its practical limit. Any good .60-size 4-stroke would do nicely. I could see the Texan flying very scale-like on a well-broken-in Saito .56'a very powerful engine for its size. Of course, any strong .46 to .48 2-stroke would also be a perfect match. LANDING AND TAKEOFF Considering the size and shape of the Texan's wing and airfoil, its slow and relaxing flight characteristics really weren't surprising. On the final, the Texan has a solid sport-plane feel. Even with the cowl stuffed with the Surpass .70, giving a slightly nose-heavy balance point, the model would slow up beautifully for main-gear landings. You don't have to grease this one in. With a lighter motor, a slightly lower wing loading and a dead-on balance point, I'm certain the Texan would make picture-perfect 3-point landings every time. For takeoffs on grass, the supplied wheels might give you a problem depending on how well groomed your field is. The wheel wells can accept slightly larger wheels, but wheel and wheel-well alignment have to be maintained perfectly for complete retraction. With its short main-gear struts and healthy tail moment, the Texan doesn't need as much up-elevator on rollout as some other designs with taller gears and shorter tail moments require. You do need to hold full up-elevator for taxiing, and some for takeoff rollout, but it can be neutralized quickly as speed picks up. Also, owing to the long tail moment, not a whole lot of right rudder is needed to keep things straight on takeoff. If you fly off a grass field that's a bit rough, you might consider building your Texan with a fixed gear. You'd have yourself a BT-14 Yale! Reprinted with permission.March, 2001 Model Airplane News Editor: Gerry Yarrish
|
|
 |
