TOP FLITE STINSON RELIANT
by Vic Olivett & Bill Steffes
A giant Golden Age classic
While planning our first Warbirds over New York event a few years ago at the South Albany Airport, we noticed a beautiful old Stinson Reliant way down at the end of the back tie-down line. As we walked toward the Golden Age classic, airport co-owner Jim Feil told us that the plane had not been moved in more than 10 years. It didn't take an expert to see that this old beauty had been neglected. With its flat tires, faded paint and worn fabric, this plane would be a great restoration project. Well, maybe in our next life.
When we saw a flyer for the new Top Flite Gold Edition Stinson Reliant, Bill and I looked at each other and immediately called Chris at Model Airplane News to see whether we could review this kit. It arrived a few weeks later; we would finally get our chance to do our Stinson - at least, a miniature version.
We opened the box to find the instruction manual, four sheets of rolled plan, balsa sticks, sheeting, hardwood parts, hardware and numerous plastic parts. We noticed on the plan that the fuselage section had to be cut and joined, as with many of the larger Top Flite kits. The 56-page manual is filled with photos, tips, instruction notes and a complete list of all the additional items needed. As you remove the parts from the die-cut sheets, mark them for easy identification later. Same goes for the laser-cut parts. The die- and laser- cutting in this kit are exceptional.
Construction starts with the tail section's horizontal stab and elevators. All of the ribs have temporary tabs that you can pin down directly to the plan (don't forget to put down your Great Planes plan protector) The construction is straightforward. Depending on the engine that you'll use, you may or may not need to sheet the entire stabilizer (we did). Top Flite recommends a 1.08 to 1.60 twin 4-stroke or the U.S. Engines 35 cc gas engine. We thought if we were going to use gas, we might as well opt for just a touch more horsepower and decided to use the U.S. Engines 41 cc. The elevators are built using a balsa core and ribs, which make them very strong. The vertical stab and rudder re built in the same manner as the stab and elevators. The trailing edges of the elevator and rudder are laminated with 1/16 inch thick balsa strip stock.
BUILDING THE WING
Wing construction starts by laminating and joining the ribs, spars and joiner box rails. Make sure you take your time here, as this assembly will determine how straight your wing will be. When you start to frame the wing, there are 16 ribs and four spars: a main spar, an aileron and flap spar and an inner main spar. The ribs are slotted along with the spars to make an egg-crate design, which adds to the overall strength of the wing. Make sure the ribs lie over the plan where indicated without forcing them. Sand the notches in the ribs if necessary for a good fit. Now glue all the ribs in place with Zap CA+. The only part that took a little extra time was fitting the joiner box. Now trail-fit the root rib, the top inner main par and the cardboard wing-joiner tube. Use the supplied dihedral gauge to check the angle of the root rib, then go ahead and glue everything together. Add the leading edge and wing tip, along with 3/32 inch thick wing sheeting, which goes only from the leading edge to the main spar.
The aileron and flap have center cores and are tack-glued into place. When we sanded the ribs for the aileron and flap, we put masking tape over the mail ribs so that we wouldn't sand them down in the process. A hinge drill guide is supplied in the kit for drilling the wing and flaps. This is important because the angle of the hinges must be correct for proper flap operation. We used Robart Hinge points on all of the surfaces.
Building the fuselage begins by laminating and framing bulkheads 3 through 9. Take your time; this assembly will ensure that your fuselage will be built square later. We used slow Zap here. Place the main stringers over the plan, then the bottom bulkheads 3 through 9. As you proceed, use a square to be certain the formers are vertical. Each former is braced by 1/2 inch square balsa to ensure alignment. Care must be taken here, as some of the bracing is permanent and some is removed later. Before you position the bottom stringers, place a straightedge from former 5 to 9 along both sides; this should be straight; if it isn't, remove any high spots. We had to remove 1/2 inch from former 6 and 1/8 inch from 7. Now go ahead and place all the bottom longerons and Zap them into place.
When the bottom of the fuselage is complete, add the top formers, along with the stringers, keeping all the formers straight. The next step is to build the forward fuselage sides; there is a left and a right side, which will build in the right thrust and down thrust that is called for. When this is complete, go ahead and put on the stabilizer and the vertical fin, making sure that everything is square and level. Now it's time to add the wing to the fuselage by building another joiner box and placing it on top and in front of former 4. I found that the rear mount should be in front of - not behind-former 5; if you place it as shown on the wing plan, it will be too far back. I also added an 1/8 inch thick aircraft-grade wood spacer to the fuselage rib to strengthen the lite-ply rib where the bolt goes through. (Top Flite has added this modification to subsequent kits.) Now place the assembled wing and fuselage rib with the joiner tube in the fuselage joiner box. Check the measurements from the wing to the tail from both wingtops. If the measurements are OK, go ahead and glue in the joiner box with some Zap 30 minute epoxy. Sheeting the front half of the fuselage is somewhat difficult because the supplied wood is fairly hard, but it's manageable if it is soaked first in ammonia and water. We opted to make both of the model's doors operational solely for the east of bolting on the wing; these were not difficult to construct.
Time to trim and mount the plastic parts supplied in the kit (cowl, windscreen, wheel pants and landing-gear and strut fairings). The fit was good, but the trim lines were light if not totally missing-especially on the cowl, where the blisters are supposed to go. Fitting the cowl to the fuselage is a chore because the firewall is down and to the right. The rear of the cowl must be trimmed to compensate for this. If it isn't, the cowl will go on at an angle, and the engine centerline will be up and to the right. We recommend that before you glue in the forward fuselage sides, you trim the left side to match the right side and also remove the down thrust. Its much easier to shim the engine to get the required right and down-thrust than to cut the cowl. Now you can mount the cowl without any trimming whatsoever. Most of the other plastic parts fit well, although there were just too many pieces in the windscreen and front cabin area for a good fit. A one-piece, molded-plastic unit of the entire front section would have been nice. All of the plastic parts are molded of heavy ABS and should stand up to the stresses a larger model will encounter.
Now for the fun part. We decided to use 21st Century fabric in red and cream and copy the full-size Stinson at South Albany Airport. We thought that this scheme would give the Stinson a little more contrast and character.
Although we followed the instructions on the 21st Century paint cans, we noticed that the paint color was a poor match to the fabric. Bill removed the paint, re-sanded each part and tried it again with a fresh can of paint. Same results; the colors were a poor match. If you want to compete with your model, we highly suggest that you have matching paint custom-mixed at an auto-supply store.
We used a Futaba T6AS radio with Hobbico Command C-65 high-torque (77 oz.-in.) servos. We have used these servos on other projects and have been very pleased with their performance; they also have a heavy-duty helical gear train.
After mounting the U.S. Engines 41 cc engine, a final CG check indicated that we needed to add some weight to the tail (probably due to the heavier gas engine on the nose). As a final touch, we used a Tru-Turn AT-6-tpe spinner and installed a Top Flite dummy radial engine and Top Flite full interior kit.
TAKEOFF AND LANDING
After we had checked all of the control surfaces on the Stinson several times, we turned it into the wind. As we advanced the throttle, the tail came up and the Stinson tracked straight down the runway. In about 300 feet, the Stinson was airborne with very little up-elevator. Climb-out was very strong, and no added trim was needed. The U.S. Engines 41 cc was more than enough power for the Stinson. After the first turn away from the runway, we brought the power back to about 1/2 throttle and the Stinson settled into a very nice cruise. The plane was very stable and required very little trim. The control settings recommended in the manual were perfect.
Landing the Stinson is very predictable; it lands very much like any other high-wing plane. Just line it up and bleed off some of the power, and the Stinson will settle in very nicely with just a touch of up-elevator before touchdown. Rollout was very smooth and straight.
LOW SPEED PERFORMANCE
When you see the big bird with its tapered gull wing, you might think it was built more for speed and not slow flight. With the flaps extended and a little power, the Stinson will fly very slowly. And even at slow speeds, the controls are all very effective. The plane had no tendencies to fall off into a tip stall; instead, the nose will just drop slightly and recovery is accomplished by adding some power.
HIGH SPEED PERFORMANCE
When we decided to go with the U.S. Engines 41, we thought we would need the extra power because this was such a large model. After the first flight, we found that it was more than enough for the Stinson. At full power, the Stinson is fast for a large high-wing plane. Just point the nose in any direction, and the Stinson will fly as though it were on rails.
Although we can't imagine many full-scale Stinson's doing so, loops and rolls were very smooth and crisp. Looping the Stinson just requires pulling back on the stick and remembering to pull the power back on the downside of the loop. With slight nose-up and full aileron, the Stinson will do a smooth, clean roll.
Overall, we think that the Top Flite Stinson has excellent flight performance for a large high-wing model.
Top Flite has done an exceptional job with the Gold Edition Stinson Reliant. The kit is outstanding and very well engineered. Building this kit was truly a pleasure, and we found only a few minor problems that were easy to correct. Don't be intimidated by the Stinson's size; it would be a great first giant-scale project.
We have both been building models for many years and have been building full-time for the last five years. It's very rare that a plane creates as much excitement at the field as the Top Flite Stinson did. The size, lines and graceful beauty of this Golden Age classic put it in a category of its own.
Reprinted with permission.
December, 2000 Model Airplane News
Editor: Gerry Yarrish