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OVER the horizon comes the new "ERCOUPE," the lightplane that can be flown with utter simplicity and handed with extreme ease under any conditions and by any pilot.

Invading the $2,000 class. the Engineering and Research Corporation of Riverdale, Maryland has brought some startling developments for the lightplane enthusiast, that heretofore were unheard of in all preceding light and sportplanes. Just by looking at the Ercoupe you can see how radical it is, with its tricycle and twin rudders. It truly looks more like a modern pursuit ship than a cracker-jack lightplane.

The Ercoupe has amazing stability -- it will not get out of control. Even with the wheel full back, straight flight can be maintained or turns performed at will. It is absolutely impossible to spin the ship. The quick take-of run, fast climb and high sustained cruising speed of the Ercoupe provides point to point transportation which will surprise arid please the private pilot. On the ground, as in the air, the plane handles with great ease, no nose-overs are possible even with full application of the hydraulic brakes.

The structure of the Ercoupe is all-metal as is the covering of all but the outer wing panels. The use of corrosion- resistant aluminum alloys in structure and covering brings to the lightplane pilot the dependability and freedom from maintenance of the large transport planes.

Powered with the Continental A-65 engine, the plane has remarkable performance with surprising economy. The maximum speed is 117 m.p.h. and the cruising speed is 105 m.p.h. Cruising range is 350 miles and the landing run is only 200 feet. Fuel consumption is but 4 gals. per hour.

The ERCOUPE lends itself very nicely towards a flying scale model because of its simplicity of construction and adjusting for flight. A beginner who has only built one or two models before should have no trouble whatsoever in building the model.

Now for the construction. We shall start with the fuselage since it is the more complicated of the parts and one likes to have the hardest job done quickly.

Fuselage

Two types of basic construction may be used in constructing the fuselage One is the half-shell method and the other is the master-stringer method. We shall describe both methods but the beginner should find the hall-shell method much simpler and easier.

As for the master-stringer method, You will note that the one stringer that is shown in grain and marked MS is of 1/8" square balsa. This is the master stringer and the entire fuselage is built on these two stringers. You will have to cut the bulkheads out in one piece each and mark their positions on the two master stringers. The bulkheads are then cemented in their correct positions. After they have set, the remaining stringers are inserted in their correct positions. This may sound simple but it is quite difficult to get the fuselage lined up with this method.

The half-shell method is far simpler although it does take a little more time. First cut out a complete set of fuselage bulkheads. You will notice that only one half of each bulkhead is shown, except bulkhead A-A. Simply make two sets of the bulkheads shown.

Now join the two pages of the magazine and pin the bulkheads at right angles to the plans, making sure each former is in its correct position. Of course you cannot pin bulkhead A-A on the plan since it is cut slut of one piece of wood, not two as the other bulkheads are.

Now that you have the bulkheads pinned onto the plans you may proceed to construct the half of the fuselage right on the plans. Install, first of all, the 1/8" square strip marked MS then add all the other stringers which are 1/16" square balsa strip. Be sure that you extend the stringers 2-1/4" past bulkhead B-B so you can put A-A in later on. You should have now completed one-half of the fuselage, the right half looking from front to rear.

After you are sure that the cement has dried, remove the side and cement the other halves of the bulkheads to their mates. Now add the stringers to this side, then A-A and the tail block which is carved from very soft balsa. Cut the piece marked L-S from hard 1/16" sheet and cement it in place between A-A and B-B. The front landing strut is now bent from 0.028 music wire and glued very firmly in place.

A small piece of soft balsa is carved to shape and then cemented behind H-H.

Although covering the nose with 1/64" sheet balsa is optional, it is advisable. It is necessary around the cockpit however.

The nose block is now shaped from a hard balsa block and a small cube of balsa is glued to the rear. It fits in the square hole located in bulkhead A-A.

Now that the fuselage is complete, sight it down for any twists and correct them if there are any.

Wing

The wing is exceedingly easy to construct and the only thing that need be done is to watch out for warps. You may build the half wing shown right on the plans and the other half may be traced and then reversed.

Pin the leading edge, trailing edge, wing tip and wing spar directly on the plans after you have shaped them out of the correct size balsa. Now proceed to cut out the necessary ribs from medium 1/16" sheet balsa. You will require two of the tip ribs and fourteen of the standard ribs. The ribs are now inserted in place and cemented.

After the cement has set on the joints, remove the half wing and check for any warps. Then proceed to make the other half wing in exactly the same manner.

When both halves of the wing are complete, block them up 1-1/2" at each tip so that you will have the correct amount of dihedral and cement the center very firmly. The center section may now be covered with 1/64" sheet balsa as shown in the plans for added strength.

Now that the wing is complete we may now build and add the two rear landing struts. Shape the two struts from hard 3/16" sheet balsa then cement them in their correct. positions on the third rib from the center, making sure that they are perpendicular to the ground when the wing has the correct dihedral. Bend the wire axles front 0.028 music wire and cement it very firmly. Give the joint between the wing-rib and the balsa strut several more coats of glue just to make sure.

The wing may now be covered with tissue or the new silk-span. The author used Silk-span and found it quite good to work with especially on the fuselage where it could be wet with water so that covering the compound curves of the fuselage became very easy.

After the wing is covered it is cemented in the correct position between B-B and E-E. The leading edge is then cemented to the bottom of B-B and the trailing to E-E. A small soft balsa block is now carved to shape to keep an even flow around the fuselage beneath the wing. If you know how, this may he just a piece of bamboo paper and serves the purpose just as well and saves weight, too.

The fuselage is now covered. If you use tissue paper you on will have to use many small pieces; if you use Silk-span you can cover the entire fuselage with only two pieces of paper, one above the thrust line (MS) and one below.

Tighten the covering on the fuselage and the wing with water and then treat it with two thin coats of clear dope and two very thin coats of colored dope. Coloring is optional although silver will give the Ercoupe a metallic finish.

Tail Surfaces and Propeller

The tail is just as simple to make as you can imagine. Two rudders are required anti they are simply cut out of 1/32" sheet balsa and smoothed down with fine sandpaper.

The stabilizer is constructed right on the plans and is made from 1/16" flat balsa strips. The leading edge is sanded round at the front and the trailing edge is tapered at the rear similar to the trailing edge of the wing. Cover the stabilizer before gluing the two rudders in place.

Cement the stabilizer in place and make sure that it is perfectly lined tip and without any warps

If you are a beginner and feel that you cannot, as yet, carve a "decent" prop, you may buy a ready-carved balsa prop of 9" diameter and cut it down to 7-1/2" and then put the shape in it. The reason for cutting it down is because most "store" props have too low a pitch.

If you know how to carve a prop then we can only say be careful and take your time during the carving, so that you have two matched blades that balance perfectly.

It is advisable to employ a free.-wheel in the prop for longer flights. These may be purchased from your local dealer.

The prop shaft is bent from .028 wire but make sure that the hoop is small enough to fit into the small square hole in bulkhead A-A.

Flying

The author's ship flew perfectly "right off the drawing board" except for a small adjustment in the rudders for a turn.

Six strands of 1/8" flat brown rubber was used as power in the original model and the ship was very fast in flight, giving a spectacular climb at the beginning of each flight. If you build your Ercoupe light enough (and it call be done) you can get away with using only five, or even four, strands of 1/8" flat rubber.

For balance use a bit of clay to adjust the model in flight. The model should be flown against torque; that, is a right circle looking from rear to front. If, under power, the model dives down to the. left (with torque) shave the prop down to a 7-1/2" diameter instead of an 8" diameter as called for in the plans. Of course for maximum duration of flights use a good winder and rubber lubricant.

On the whole, the model is very simple to construct and fly, but if you do run into any difficulty please don't hesitate to write the author care of this magazine, enclosing a self-addressed stamped envelope.

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