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Chapter 2 - “Aeronca Sedan” For Tyros

Even if you have never before constructed or flown an engine-powered model airplane, there is no reason why you cannot enter this phase of the hobby by starting with an attractive scale replica. This statement is true only if your initial subject possesses the qualities required for stable, easy-to-control, and relatively slow flights. These requirements plus simple, basic construction will insure success with the first model airplane venture attempted.

The smallest size model, powered by a "half-A" engine, is recommended for the no1vice. A warp-free wing of solid construction, in lieu of the more complex "built-up" type which utilizes ribs, spars, and covering, is suggested, not only because of its simple building, but because of its ability to withstand abuse and the ease of repairing. A fuselage, or body, carved from a solid block of balsa is also recommended for the tyro. This, of course, must be hollowed to make way for the fuel tank and controls, an easy job for anyone who likes to whittle. A simple landing gear and wing attachment are essential.

From a design standpoint, generous wing area coupled with a long tail moment arm (distance between wing and horizontal tail surface) will produce moderate speeds with controls which are easy to handle. The shorter the tail moment arm, the more sensitive the controls. Monoplanes are also considered best for the beginner in view of the fact that only one wing requires alignment. The high-wing-design monoplanes possess more inherent stability than other types, therefore these can also be considered good beginner material. There are scores of model airplane kits on the market today that meet the above requirements for easy building and flying. The majority of these kits are prefabricated. By this, it is meant that the fuselage, wing, and empennage (tail) are all supplied ready-cut and carved. All that remains to be done is sandpapering. Items such as the wire landing gear are bent to shape. Such kits are extremely popular. However, there are many builders who prefer to construct their models from raw balsa and, as a matter of fact, much more can be learned in this manner. It is the author's opinion that the novice should attempt to build directly from plans in his first attempt at modelling in order to learn the most from each component.

"Scientific" Photo

Of special interest in this photograph of our "Aeronca Sedan" model is the control line guide fastened to the wing tip. This is bent from wire. Model is very attractively colored and simple to build and fly. Nose is sheet aluminum, pinned to the fuselage. Craft is virtually indestructible

J.  Rehfield  Photo

Engines should always be checked for proper operation before flying. Note the flying equip-ment required: Batteries with long wires and "alligator clips", control handle (Jim Walker 'U-Reely" shown), and fuel can with plunger pump (strapped to batteries for convenience.) Model is the Messerschmitt 109, an excellent type for sport or beauty.

The "Aeronca Sedan" was selected for the novice because it fulfills all the requirements outlined above. The author designed this model for the Scientific Model Airplane Company of Newark, N. J., which manufactures it as a prefabricated kit. Hundreds of youngsters have learned to fly successfully with this model. We shall describe the construction procedure for completing this model from the accompanying plans. Plans have been presented one-half actual size. Before we begin construction, a few words about the full scale "Aeronca Sedan" may be of interest.

For over three decades the Aeronca Manufacturing Corporation has been one of the world's leading light plane designers and builders. The "Sedan" is the latest plane produced by this company. Several "Aeronca Sedans" are sure to be seen at any public airfield because this plane is one of the most popular private planes in the world. Numerous business executives use the "Sedan" on business trips and pleasure jaunts alike. Powered with a four-cylinder, air-cooled, oppossed-cylinder pancake-type engine, the fuel consumption is comparable to the average automobile, while maintenance costs are considerably less than might be expected for aircraft of this type.

With minor modifications, the U. S. Army uses Aeronca planes for liason ambulance and gunnery spotting service and as important personnel carriers. Considerable thought has been given by Army leaders to bomb-dropping and ground-troop machine-gunning tactics using these light planes, especially because of their excellent handling qualities at low speeds.

It is due mainly to such inexpensive airplanes as the "Aeronca" that there are so many licensed flyers in the United States ready to fly bombers and fighters in any emergency.

Construction should begin by enlarging the plan by doubling the size or by photostating. Trace the top view of the fuselage onto a medium-soft block of balsa wood and cut out with a coping saw, which is available at any hardware or 5-and-10-cent store. Sand smooth with 1/0 sandpaper and trace the side view onto the side of the block. Cut this out with the saw and sand. Trace and saw the plywood bulkhead-firewall and cement to the front of the fuselage using plenty of the adhesive.

Using a sharp knife, such as an X-Acto No. 26 blade, carve the fuselage to shape following the sections shown. Sand well with 1/0 sandpaper. The fuselage must be hollowed at this time and we recommend an X-Acto

 gouge for this purpose. Cut a little at a time. Once hollowed, sand the interior lightly and drill a ¼" diameter hole in the inside roof to receive the bellcrank mount. Cement this mount securely in place. Either a hardwood "nose button" or ¼" dowel can be used.

Air Trails Photo

The author flies a Spitfire model in a court near his home. Wide dead-end streets, parking lots, school yards ana other paved surfaces are ideal for operating control line craft. Baseball diamonds, smooth corner lots or close cut grass can also substitute for the abovementioned sites.

Trace and cut the tail surfaces from 1/16" sheet balsa, using a single-edge razor blade, and sand smooth. Join the two halves of the elevator, using a piece of 1/16" dowel as the joiner. Purchase a metal commercial control horn and firmly attach to the elevator as shown. Cut strips of handkerchief-weight to ⅜" x ¾" and use these to hinge the stabilizer to the elevator as the plans illustrate. Notice that one half of this cloth strip is cemented to the top while the other half is cemented to the bottom of the two components as in Chapter One.

While this is drying, the wire control rod can be bent to shape as shown and slipped through the fuselage slot. Slip the offset end into the horn and then cement the stabilizer firmly to the fuselage. Hold in place with straight pins until dry.

Trace the outline of the wing on a piece of M" x 3" x 22" medium-soft balsa and cut to shape. It will be found that only the wing tip requires cutting because the wing is 3" wide. Study the wing section shown in the side view. This is called the "Airfoil"; carve the wing to meet this section. Shape the tip and sand the wing well by wrapping 1/0 sandpaper around a block of wood approximately ½" x 2" x 3". Use plenty of cement to attach the wing to the fuselage top. A wide variety of commercial bellcranks is available to fit this model. "Veco", "Scientific", "Pylon" are some of those on the market. The purpose of the bellcrank is to convey the push-and-pull movement of the control wires to the control rod which operates the horn, thus causing the elevators to move up or down, thereby forcing the craft to climb or dive in accordance with the flier's desire. Two 14-inch lengths of .016" diameter music wire should now be attached to the bellcrank by twisting the ends as shown. Slip these wires through the two fuselage holes and screw the bellcrank to the mount, being certain to insert the control-rod end into the remaining bellcrank hole. The control system must be able to operate freely without binding.
Aeronca Photo

Color markings and profile are clearly indicated in this photo of the full size "Aeronca Sedan." Note the navigating light on the wingtip and fuselage step just forward of the wing strut. Exhaust stack protrudes below the cowl.

Cement the fin and rudder in place. Note the rudder offset on the fuselage top view. This is most important in order to keep the flight lines taut.

Bend the control-line guide from wire and install as step No. 4 illustrates. The landing gear is bent from 1/16" music wire following the pattern. Use flat-nose pliers for this operation. The completed landing gear is then "sandwiched" between two pieces of plywood and plenty of cement applied. When dry, this assembly can be firmly cemented into the fuselage by applying several coats of the adhesive.

Many engines are available with integral fuel tanks in which case the separate internal fuel tank which is illustrated on the plans can be eliminated. The cowl should be made longer to accommodate the attached fuel tank.

Numerous commercial fuel tanks can be purchased to fit this model. "Maeco", "Perfect", "Darwin" and many other firms market these tanks. About six inches of clear plastic fuel-line tubing is required to connect the fuel tank. Drill a hole in the plywood firewall to admit the fuel supply line.

Aeronca Photo

Many "Aeronca Sedans" are fitted with floats. Your model "Aeronca" can be flown from water as well. Chapter Ten describes seaplane flying and contains plans of Moats for your "Sedan" model. It is, however, advisable to fly the craft as a landplane first in order to get acquainted with the flight characteristics.

Attach the filling and overflow tank extensions and install the tank. Cement to the fuselage side and brace with scrap balsa. Make certain the filling and overflow lines protrude through the fuselage.

Cut out the 1/16" fuselage bottom from sheet balsa and cement in place. Sand smooth and round the sharp corners when dry. Trace the metal cowl pattern onto .008" aluminum sheet or similar material. Tin-can metal will serve as a good substitute for this item. This can be cut with tin snips or an old pair of scissors.

The alcohol fuel used in model airplane engines will dissolve ordinary cement and lacquer or dope. It is therefore, imperative that the cement and dope that is used for engine powered models be of the "fuel proof" variety which assures that they will be impervious to the action of the alcohol fuel. When "fuel proof" products are not used the entire model must be painted with a clear protective liquid called "fuel proofer". Fuel proof dope and cement are, however, always recommended.

The engine can now be installed. Any engine from .039 to .074 cubic-inch displacement can be used. These are classed "Half A" and are the smallest available. The engine is screwed to the plywood, using 3/8" long round-head wood screws.   Some of the engines that will fit this model are;

J.  Rehfield Photo

Proper launching technique is demonstrated in the release of a Messerschmitt model. It should be noted that the model is merely released and not pushed. The boy will step away immediately in order tb*te clear of the plane as it roars around the circle.

"O.K. Cub .039", ".049" or ".074", the "Wasp," "Cox .049", "Tornado", and others which your hobby dealer will be glad to recommend. These engines range in price from $3.95 to $6.00. Connect the fuel line to the engine, being sure to eliminate any kinks which might impair the flow of fuel. Add the wheels next.

Straight pins driven into the fuselage through the metal hold the cowl in place. Use about six pins. Add cement.

Before colored dope is applied, the pores in the balsa must be filled in order to obtain a good paint job. Brush on three coats, allowing each coat to dry thoroughly. Use a ¼" or ⅜" soft hair brush for applying all liquids. Sand the finish with 3/0, followed by fine finishing paper. Do not apply the color until you have obtained the finish you desire with the "Sanding Sealer." Colored dope, which is like lacquer, will not act to seal the wood grain and, since it dries quite hard, is difficult to sand thoroughly. Apply two or three coats of dope for a good-looking average finish. Paint the light color first and, after allowing at least a half hour for thorough drying, mask the model along the color lines, using paper masking tape available at most hobby shops or hardware and paint stores. Make certain that the edges of the tape adhere well to the model by pressing them carefully with the fingers to prevent the paint from bleeding through. Fuel proof dope is recommended.

Aeronca Photo

Much nose and cabin detail is evident in this flight photo of the "Aeronca." Notice, also, the large landing lights in the near wing tip. These appear only in this one wing. The meticulous model builder can use costume jewelry rhinestones to simulate these lights and cover them with sheet celluloid.

With painting completed, it is optional, on a model of this type, whether to rub the finish or not. Rubbing compound is a mild abrasive in a paste wax base. When this is applied to the finished paint job with a piece of absorbent cotton and rubbed briskly, it can create a rich lustre comparable to the finish of the finest automobile. Speed models and beauty entries are always rubbed; however, the meticulous model builder will hand rub every model he creates.

Miscellaneous items like the 1/16" sheet balsa wing and landing-gear fairing struts are added at this time. These should be painted before installing. The thread tail rigging is sewed on with a standard needle.

 Windows and license numerals are cut from "Wonder-cal". This product is a sheet of solid color fuel proof decal. The figure you desire must be drawn on the sheet with soft pencil and then cut out with razor blade or sharp scissors. This figure is now immersed into warm water for about 15 seconds and then the thin colored film is slid off the paper backing onto the model. Patting dry with a soft cloth causes the film to adhere tenaciously to the model. Draw on the paper back of the decal.

"Scientific"   Photo

This model of the 18" wing span "Stinson Voyager" is another excellent candidate for the novice. Observe the close resemblance to the "Aeronca Sedan." Moderate wing area and tail moment arm plus husky construction make up the requirements for easy flying. The author designed this model for a kit manufactured by the-"Scientific Model Airplane Co." and many inexperienced youngsters have flown these craft successfully.

Once the craft is completed it should receive two coats of clear fuel-proofer, thereby adding the final touch to your handiwork, if fool proof dope was not used.

This model "Aeronca" is flown in the same manner as any other control-line type. These craft are controlled in the same fashion as the "Whip" model described in the previous chapter except, of course, that no whip is required, since the engine in the craft drives it through the air. Before any flying is attempted, the model should balance as noted on the drawings. Addition of weight in the nose or tail should remedy any unbalanced condition. Use the same control handle described in Chapter One and securely tie on two 25-foot lengths of carpet thread, well waxed. Tie the remaining ends to the lead-out lines on the model. Make certain that the "up" line is connected to the correct side of the bellcrank.

A smooth-surfaced flying site, such as a school yard or paved parking lot, is recommended. The lines should be carefully stretched out on the ground and the control handle placed in the circle center. Start the engine in accordance with the manufacturer's instructions and, when it is operating smoothly, walk to the circle center while your helper keeps the model from taking off. Make certain that the craft is facing downwind. This will enable the model to gain speed on the ground before it faces the wind and takes off. Once you are in the center of the circle, check the controls again and then signal your helper to release, not push, the model. As the plane gains speed keep the controls in a neutral position and it will take off without assistance. Should this not be the case, a very slight "up" elevator will lift the craft into the air. Neutralize the controls immediately once the model is airborne. During this first flight, the plane must be carefully observed and certain characteristics noted: control response, maintaining line tension, or nose or tail heaviness with neutral controls. During flight the lines must be taut at all times. Should the lines begin to slacken, a step or two backward will restore tension.  Lines have a tendency to slacken when the model is flying into the wind and when the model is between the flyer and the wind. If the lines repeatedly slacken it is advisable to offset the rudder an additional M inch.

 This interesting comparison between a specially designed beginner's model, the Tester's "Freshman", and a scale model candidate for beginners, the "Monocoupe", illustrates the great similarity in basic design. Wing area and tail moment arm are identical. Outline of fuselage shape does not affect performance to any great extent. Such scale models can be flown, successfully by the tyro.

Scientific Photos

The two "Piper Cub" models shown here were designed by the author for the Scientific Model Airplane Company, who manufacturers both craft in kit form. The construction of these models is virtually identical to the "Aeronca Sedan" described in this chapter.

Note the red cross insignia of the landplane "Cub". This is a replica of the ambulance-rescue planes used by the U.S. Navy during World War Two. The color is dark blue with sky blue undersurfaces. You can paint your Aeronca in similar fashion if desired. Crosses are red on a white field.

The "Cub" seaplane clearly illustrated to the author the aquatic ability of small models by performing beautifully on its very first flight. See chapter Ten regarding the application of floats to your "Aeronca Sedan".

"Scientific" Photo

The tyro does not have to limit his selections to monoplanes. Many craft with two wings fulfill the specifications for beginner craft. Wings should, however, be attached directly to the fuselage as shown in this photo of "Scientific's" Beechcraft, designed by the author. This attachment insures greater strength and facilitates better alignment than the use of struts.

"Scientific" Photo

The fact that beginner models are easy to build and fly does not mean that they cannot also be attractive in appearance. This 18" low wing "Boeing P-26a" possesses all the features required for the tyro's first model and yet affords appeal that rivals the most handsome beauty winner. Note the long distance between the tail and wing in order to prevent sensitive controls. Another "Scientific" kit designed by the author.

Commercial fuel tanks for this size model allow engine runs of from one to three minutes. The engine run, of course, controls the length of the flight. Generally the only warning that the engine is about to stop is a slight speed up or an occasional sputtering sound. Whether or not there is a warning, the model is certain to travel at least a quarter lap after the engine stops and before it begins to settle to a landing. While the model settles, keep the controls in neutral, "leading" the craft to maintain landing speed. When your ship is at an altitude of about 3 feet, gently apply slight "up" elevator for a perfect three-point landing.

Care of control lines, especially thread lines, cannot be overemphasized. These should not be stepped on and must be inspected periodically for weak spots which could prove to be danger points. Never attempt to fly over the heads of spectators. Always make certain that the path is clear before you take off. By following a few simple rules and common sense, much safe entertainment is yours with model airplanes. Once you become proficient in operating this "Aeronca Sedan", you can progress to the more advanced speed, stunt, and multi-engine craft found in the following chapters.

Scientific   Photo

Another model ideally suited to the novice is this Scientific kit of the "Curtiss P-40 Flying Tiger" World War Two fighter plane; designed by the author. Despite the low wing, streamlined appearance this model proved as easy to fly as the "Aeronca Sedan".

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