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This item is discontinued. GREAT PLANES GIANT PT-19 ARF
SPECIFICATIONS RCM PROTOTYPE SUMMARY
Introduction: The PT-19 was conceived as a primary trainer for full-scale American pilots in preparation for the war effort looming on the horizon during the late 1930's. Often called the "Cornell," this plane was built in near record numbers for that time frame. The basic flying characteristics of this stable trainer have been successfully translated into this model. Great Planes have introduced an excellent ARF that qualifies both as a warbird, is IMAA legal, yet only requires a standard 4-channel radio with five servos, and an engine ranging from .61 2-stroke to 1.20 4-stroke. Our PT-19 arrived in a very large box (53" x 17" x 11") and was safely delivered without any damage to the contents. Each of the major components was wrapped in a clear plastic bag and surprisingly did not need any re-shrinking, as the colorful MonoKote covering was drum-tight. The hardware package was safely secured and its contents were of a very high quality. Two large sheets of decals were located on the bottom of the box along with a sheet of uncut Great Planes hinging material.
Construction (Assembly): Like most ARF's, the modeler only receives an instruction manual (24 pages), as there is no need for plans. The instruction manual contains information that separates it from many other manuals in that they include information pertaining which MonoKote colors were used, replacement part numbers, and a complete listing of all the hardware supplied. A listing of additional items needed to complete this project is also furnished in the manual. Like most ARF's, the PT-19's assembly starts with the wing by installing the two aileron servos. A 12" aileron extension (per wing panel) was required to reach from the servo to the opening in the wing. For this purpose, two Hobbico Pro HD servo extensions were used (P/N HCAM2710). These were then connected to a Hobbico PRO HD "Y" connector (P/N HCAM2750). The rational behind using these parts is due in part to the fact that they are constructed of 20-gauge wire and also have a definite "click" when they are connected. Just to be on the safe side, some heat shrink tubing was used over the various connections. The joining of the wing panels was accomplished by first gluing together three plywood wing joiners and then fitting the wing halves together. The amount of dihedral was not given so the two panels were aligned as tightly as possible and held together by some 30-minute Z-Poxy y Pacer. The resulting joint was gap free! The preformed landing gear was 3/16" diameter and fit into the landing gear blocks without any difficulty. The non-functional plastic landing gear fairings were added for scale effect. The two supplied large main wheels were quite light and whereas this plane will be flying off a grass field, their longevity should not be of any concern. The stabilizer and fin were installed without any problems as their openings were tight fitting and self-aligned! The hardware for the tail wheel attachment could be improved in my opinion as the assembly might transfer the pressure directly to the rudder.
Covering: The color scheme chosen by the (then) Army Air Force was one for visibility and, one has to admit, this plane will turn some heads when it appears on the flight line. The basic blue was complemented by four other colors, Red, White, Yellow and Black. Our model showed no signs of wrinkling and the covering was expertly applied. One area that could use some additional fuelproofing is in the forward wing cradle area, as the exhaust will be diverted along the bottom of the fuselage. Perhaps in future production runs the MonoKote could be trimmed further from the edges. To solve this dilemma, some scrap Blue MonoKote was applied. Engine: The O.S. .91 Surpass engine was easily mounted to the supplied engine mount, and with the addition of a special exhaust header pipe (OSMG2624), the muffler was totally concealed inside the fuselage and cowl. This header has a 90-degree bend, permitting the standard supplied exhaust header to be attached along with the muffler, without the need for additional cutouts. To assist in starting the engine, a Du-Bro Remote Safety Ignitor (P/N 794) was routed through the firewall to the rearmost cockpit floor and located there. Only the high-speed needle valve extension exits the cowl. Radio: There was ample room to install the servos, receiver and battery. Two metal elevator pushrods blend into one near a single servo, but there is enough room for an additional elevator servo if you so desire. The all-metal pushrods were fed through the fuselage inside the pre-installed outer sleeves and worked without binding of any kind. A JR FX631 radio was chosen because of its ease of use and the fact that it features those options needed for a plane of this simplicity. A total of five standard JR 537 servos were required and an opening had to be made in the servo tray area so the servo wires could exit this area and reach the receiver. A Du-Bro Kwik Switch & Charging Jack (P/N 207) was installed on the cockpit floor in front of the first pilot. Both cockpits were bare balsa and had to be finished before installing any of the occupants, which by the way were from Nelson Aircraft Specialties (in the front) and Williams Bros. (in the back). By placing the JR 600 mAh battery under the supplied fuel tank, our PT-19 did not require any additional weight to balance at the suggested location. The use of the Great Planes C.G . Machine (P/N GPMR2400) made this procedure easy and accurate.
Final Steps: To finalize the plane, both of the pilots' windscreens were painted with Testors Black, installed with some Pacers Zap-A-Dap-A-Goo along with two button head sheet metal screws from Great Planes (P/N GPMQ3120). This type of screw was also used to hold the cowl in place, giving the appearance of a rivet! The supplied "Turnover-post" (which was expertly pre-finished) was glued to the fuselage with a couple of dabs of Zap-A-Dap-A-Goo. Also a Great Planes aluminum spinner nut (P/N GPMQ4630) was installed, giving the front end a more scale-like appearance. No mention was made in the instructions concerning either the use, or installation, of the cockpit combing that was included. It was merely sliced along the entire middle of each piece and attached to the fuselage with some Zap-A-Dap-A-Goo. The large decals were applied by first cutting out the item to be installed, then placing them in some warm water (with some dishwasher soap added). The decal was then separated from its backing. Failure to do so will result in those large round decals curling back upon themselves and they will stick together! Failure to follow the suggested procedure will make positioning very difficult if not impossible. Whereas almost every PT-19 sports the number "24," it was decided to just use the "4" to show some (but not much) creativity! A couple of nice little surprises were included in this kit. The first was the inclusion of an additional piece of plywood that has the same mounting holes as the wing. This piece can be glued in the front of the fuselage cradle permitting the temporary positioning of the wing (vertically) so the aileron connections can be made without the need of additional assistance. This will make your set-up and disassembly easier. The second item worth mentioning was the incorporation of a cutout in the instruction booklet that includes your name, address, etc., that can be taped inside your plane. For those modelers in the USA, this is a requirement of the AMA, providing the AMA number is not displayed on the top right wing panel. Nice touch Great Planes. The all-up weight came to a very respectable 10 pounds, 4 ounces. This resulted in a very favorable wing loading of only 23 oz./sq. foot! The suggested control throws were easily obtained using a Great Planes "Accu-Throw" deflection meter (P/N GPMR2405). So with a painted 16 x 8 Top Flite wood prop up front, it was time to move this plane from the workshop to the flying field.
Flying: The day of first test flights was perfect: gentle breezes, sunny sky and no one else on my frequency. The brand new O.S. .91 Surpass was started for the first time at the field and, to everyone's surprise, not only started on the first flip of the prop, but also idled very well. One tank of Cooper's Custom Blend 15% was run through the engine with the cowl removed to make it possible to monitor any heating or throttle position problems - which did not develop. My son Jonathan had the honors of test flying the plane for the first flight and then yours truly flew the second flight. The first flight was completed without the cowl with the majority of the flight flown at 1/2 throttle. The PT-19 wanted to climb so a significant amount of down trim was needed to maintain level flight. With the O.S. .91 running on the "rich" side, the PT-19 could complete graceful loops. The rolls were far from axial and more like barrel rolls. When both the elevator and ailerons were changed to high rates, rolls smoothed out, and resembled a full-scale maneuver. The landing was very gentle and used up about half our 200 foot grass runway. For the next flight the cowl was put back on, the engine leaned out a little and we tried some additional maneuvers. As set up, this plane definitely lacks unlimited vertical, but extended stall turns were possible. That same maneuver looked so much better when done closer to the earth, so we entered and exited about 25 feet high. Inverted flight required very little elevator input, and full stalls were next to impossible to execute. The PT-19 just mushed forward when full up elevator was used to force the stall. Full rudder and aileron were then added and a slow spiral resulted. Touch and goes are a thing of beauty with this plane. Approaching the runway, the PT-19 was always rock solid, and when the O.S. .91 was reduced to idle, the plane landed itself. Yes, this plane, err warbird, was designed for those lazy flying days when you want to see a bright colored plane (that isn't solid yellow) putting around the sky.
Conclusion: If someone would like to try a giant scale warbird for the first time but only has a basic 4-channel radio and a .61 engine or larger, the Great Planes PT-19 might just fill the bill! This plane doesn't require any more expertise in building or flying than the ubiquitous .40 sized trainer. Likewise, the flying abilities of the plane make for a gentle, lazy day type of flying. So when you get yours, you can now enter a scale contest, IMAA event, or just "Wow" the pilots at your field with slow and gentle touch and goes! The choice is yours - enjoy! Photos by Jerry Festa. Reprinted with permission.September, 2002 R/C Modeler Magazine Editor: Patricia Crews
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