GREAT PLANES T-CRAFT
FIELD & BENCH REVIEW
by Randy Randolph
Manufacturer: Great Planes
Wingspan: 56 in.
Wing area: 497 sq. in.
Weight: 3 lb., 10 oz.
Wing loading: 16.5 oz./sq. ft.
Length: 40.75 in.
Engine req'd: .20 to .32 2-stroke; .26 to .30 4-stroke
Engine used: O.S. .25LA
Radio req'd: 4- to 5-channel with 5 S-33 servos
- Well designed and engineered.
- Excellent plans and instruction manual.
- Nice die-cut parts.
- Complete hardware package.
- Difficult plastic-cowl and wheel-pant assembly.
- Weak landing-gear fairing mounts.
.20-size sport-scale classic
Assembling a good kit is an excellent way to develop model-building skills. A lot of the pure drudgery has been eliminated from modern kits, but the pleasure of creating something with your own hands remains. The Great Planes T-Craft kit is no exception.
The T-Craft is a .20-size scale airplane that needs a fair amount of work. Almost anyone who can read and use basic hand tools, and who has built a few sport kits, should do a good job.
When I first opened the kit, I saw the formed, three-piece cowl, the wheel pants and the instruction manual. Neatly bundled sticks of wood lie below the manual, followed by stacks of die-cut parts. A clear plastic bag contains the hardware and all of the smaller parts. An engine mount is also included. I chose to use an O.S. .25LA engine to power the T-Craft and am pleased with the results.
The die-cutting is well done, and the parts require only minor trimming for a perfect fit. The tail surfaces are built up rather than solid. Once I had assembled them, I sanded them on both sides. I used masking tape to hold the movable surfaces to the fixed ones when rounding the edges.
After sanding, I joined the elevators to the wing halves with the provided 3/32-inch wire. I then separated them by trimming through the leading edge (LE) spar. After a final sanding, they were ready to be hinged. First, I laminated the two spruce main spars so that they were thicker at the root than at the tip. Then I notched the bottom spars where they bend up slightly to form the tip. Both wing halves can be built at the same time if the building board is large enough, but it's better to build one at a time so that you become familiar with the procedure.
I pinned the bottom main spar over the plan with 1/16-inch spacers. I added the ribs, followed by the wing's trailing edge (TE) and the top main spar. Each of the ribs has removable flanges on the bottom to hold it in place on the plan. This is an old system that works well on anything other than a flat-bottomed wing.
Next, I added the aileron cutout spar, followed by the aileron's TE. The sub-LE, all spars and their webs, as well as the top of the aileron TE must be completed before the wing is removed from the plan.
Join the wing halves with plywood dihedral braces. The provided dihedral jig raises one wingtip the proper amount, while the other is flat on the bench. One of the center ribs on my plane was brittle, and the bottom LE split every time I slipped a dihedral brace halfway through. After repairing these breaks, I began sheeting the LEs and center section. The kit provided just the right weight of "A" grain, 1/16-inch sheet to make this very easy.
The ailerons are assembled next. I glued the die-cut backbone to the 1/4-inch-thick spar and added the ribs to both sides. Instead of using the supplied rectangular pieces of balsa that needed to be sanded to shape, I sliced them diagonally and used the long triangles as ribs. They still needed sanding to fair the ailerons smoothly into the wing, but not as much. Actually, quite a bit of sanding and shaping is needed to get the wings to the covering stage, but they look good when they are ready.
Each aileron has its own servo, and the mount is installed in the wing. I drilled the die-cut plywood servo mounts before I installed them. Before you cover the wing, install the servos and connect them to a Y-harness that extends through the wing's center section and into the cabin area.
The fuselage sides are built right on the plan. One of the sheets that contained part of the fuselage was accidentally left out of my kit, but a call to Great Planes' customer service brought the part within the week.
While I was waiting, I built one half of the fuselage and completed the laminating of bulkheads. When the two sides have been built, the fuselage can be assembled like a jigsaw puzzle with large pieces.
Die-cut fore and aft decks ensure that the tail surfaces are true when they're attached. A couple of the plywood bulkheads were slightly warped, but the notches in the fuselage side seemed to correct this.
Installing the engine and motor mount is very easy and is clearly explained in the instructions. To make the installation easier, you should install the engine, fuel tank and throttle linkage before adding the top and bottom sheeting. After the bottom and forward sections of the turtle deck have been sheeted and the 1/8-inch hardwood dowel stringers have been added, you should test-fit the windshield.
I cut out the preformed windshield along the lines as instructed, and it fit perfectly without any trimming or adjustments. I then put it aside until I was ready to complete the covering and final assembly.
The cowl comes in three pieces that must be cemented together. The instructions did not clearly identify the proper places to trim; I trimmed for over an hour before I found the right "embossed" lines and was able to properly fit the pieces together for gluing. Because the cowl must be removed to refuel, you may want to add a refueling device.
Before you cover the wing, make a small hole in the bottom of the wing's center sheeting to allow the servo leads to exit. I installed the wiring before I covered the wing and used masking tape to anchor each lead below the servo mounts.
I used the MonoKote covering recommended by the manual and tried to match the red and white color scheme on the box. I also used MonoKote on the plastic parts because I had no matching paint—and it worked! There was just enough heat to anchor the MonoKote.
Because I top-hinged the ailerons, I had to relieve the bottom (LE) of the aileron spar to allow for downward movement. The aileron hinge system was the only change I made to the plane.
Following the instructions, I attached the landing-gear fairings to the legs with short pieces of rubber band. This worked fine for a while, but on the second flight, one fairing came loose, and the other almost separated. I glued them back but later added strips of MonoKote to hold the landing-gear legs to the fairings and heavy-duty strapping tape to hold them to the fuselage bottom.
To control the T-Craft, I chose to use five Futaba S-33 servos, two of which I mounted in the wing for aileron control. The receiver is an FMA Direct Fortress, which I powered with a 600mAh battery pack. Everything fit nicely, and for such a short-nosed airplane, the T-Craft balanced perfectly.
This is a well-engineered kit. The plans and the instructions are great, and using a small-scale plan as the centerfold is a very nice touch. This is not the easiest kit to build because there is more to it than a square box trainer, but it is not exactly difficult, either! There is plenty of room for the fuel tank and radio, and it's easy to adjust the external ailerons to achieve the correct trim.
Since I do not normally build scale models, I have no idea how close to scale the finished product really is, but it looks a lot like the only T-Craft I ever flew. That was 45 years ago!
The wide landing gear and generous wheels provided solid ground control, and the takeoff was straight with very little correction. The wing struts were in place for the first test flights of the T-Craft. The airplane flew well with the struts, but control response was slow. At full power, this was not a real problem, but as with its full-scale prototype, coordinated rudder was necessary for smooth turns. At 1/2 throttle, the O.S. .25LA produced gentle, slow flight with no tendency to stall.
Once I removed the struts, the T-Craft became another airplane! Control response was crisp, and much less rudder was required for smooth, coordinated turns. Furthermore, less than 1/3 throttle kept it in the air. Landings improved with a nice smooth approach and an easy hold-off to nice 3-pointers!
Reprinted with permission.
With control throws set at maximum, the T-Craft has all the moves of an advanced trainer. Loops and rolls, stall turns, wingovers, snaps, spins and inverted flight are easy and done with style. Though not a true aerobat, the T-Craft is capable of just about anything you want it to do.
August, 2001 Model Airplane News
Editor: Gerry Yarrish