Model aircraft

“ To the whir of the propellers, which form two blurred circles in the air, the model quickly climbs upward, rights itself and speeds away on its long flight. The young aviator's skill is revealed to every eye by the angle of the ascent, the altitude and the ability to gain equilibrium aloft. The more you know about aviation, the more absorbing is your interest in a flight.
A good rise is usually observed in silence. By the time the model has reached the middle of the armory, more than one hundred feet from the starting line, enthusiasm is aroused. ”

“ Like the famous designers and pilots of man-carrying craft this younger generation of designers give their names to their machines. Our young designers, as a rule, confine themselves to developing a particular type of machine. A comparison of the models of the same builder for a year or more will usually show that the same general form and arrangement of the planes remain the same.
The Percy Pierce model, which borrows the name of its designer, is probably the best known of these model aeroplanes. ”

“ In other words, if the motor of a large machine were started and the aeroplane launched without a pilot, would its chances of flight be as good, in proportion to its size, as those of our best model aeroplanes? A model aeroplane which flies 300 feet performs as remarkable a feat as would a large machine flying, unguided, a mile or more. The progress in the construction of model aeroplanes, in brief, already deserves serious scientific consideration. ”

“ Some efficient wing plans are given by Fig. 37.
Stated briefly, there are essentially three kinds of model aeroplanes. First, the scale model, which is a reproduction to scale of a real machine; second, a modified copy of a large machine, which is so designed as to resemble in general form some well-known prototype, while retaining by means of a suitable motor, generally twisted rubber, some ability to fly; third, a machine which does not in any way follow the lines of full-size machines, and is built for flight only. ”

“ The planes may be readily mounted on a small dowel stick. A small propeller and a motor a foot in length will answer. A small semi-circular fin should be set below the rear plane to act as rudder. First cover the frames with a stiff paper and after you have succeeded in adjusting it, this may be replaced by cloth. The model will not fly far, or very steadily, but it is interesting to practice with. The balance of the model is open to criticism; for the center of gravity appears to be too far forward. ”

“ Although planes so built are exceedingly strong, it is not possible to make quite so neat a job of them as with spruce or maple.
Another method of building main planes is to use spruce or birch spars with piano-wire ribs, these latter being bound to the former.
For single-spar models the main spar should be tapered fore and aft from a point one-third of the length from the front of the machine. Where it is necessary to pierce the spar of a model aeroplane for the reception of a kingpost or other member, silk tape binding should be used, the joint being soaked with clean, weak glue. ”

“ To give you some idea how slight a thing will make a model behave badly, I fitted a skid to protect the propeller underneath the aeroplane, and the result in retarding flight could be seen very quickly, although the weight of the skid was almost nil. [3] To all model makers who wish to make a success I would say, strip all that useless and heavy chassis off, cut down the 'good, honest stick' that you have for a backbone to half its thickness, stay it with wire if it bends under the strain of the rubber, put light silk on the planes, and use an aluminium [4] propeller. ”

“ All of the successful monoplanes aloft to-day, the Bleriot, Santos Dumont, Antoinette and others are driven with their larger or soaring planes forward and their smaller stability-planes in the rear. The day may come when these machines will be reversed. The model before us may point the way to a great improvement in the building of air-craft. It is an important principle for the builder of model aëroplanes to bear in mind. ”

“ The biplane forms are being abandoned by model builders, as well as the biplane form of elevating planes. In place of the models made from fifty or more members, we now find excellent models, capable of much longer flights, formed of but a dozen pieces. The builders of model aeroplanes are keeping pace with the development of the man-carrying machines, if they are not passing them, in developing the flying machine of the future. ”

“ The most delicate workmanship is to be found in every detail. The planes are controlled by a complete system of wires and levers centered at the driver's seat, exactly as in the large man-carrying machines.. The wings may be flexed and the guiding rudders turned from side to side or their angle elevated or depressed by the slightest movement of the controlling devices. The model is equipped with a miniature Gnome engine especially imported for the purpose. The materials employed in constructing this model alone cost upwards of $500. ”

“ CHAPTER I MODEL AEROPLANES OF 1911 For the average boy there is no more stirring music than the brisk, whirring note of his model aeroplane. Let the propellers spin steadily for ten glorious seconds, and the journey spans a couple hundred feet or more. Double the time and the flight becomes a triumph. Out of the ingenuity of thousands of boy aviators, the world over, has come a surprising development of the model aeroplane. The experimental stage is passed. Any bright boy may now build a model aeroplane which is certain to give results. ”

“ Working along different lines, the builders of model aeroplanes, widely scattered, seem to be gradually developing much the same type of air craft. The tendency is toward the construction of much lighter and more logical models than last year. In place of the complicated models supported by several broad planes, we find the most successful amateur aviators expending all their ingenuity upon simple monoplane forms. ”

“ Fig. 35 is the simplest possible form of model aeroplane fuselage, if such it can be called.
Choice of materials and the method of utilising them to the best advantage, so that the machine is strong without being unduly heavy, is a phase of model aeroplaning that calls for some care and judgment. There is a very erroneous impression prevalent among novices that packing-case wood or similar material is suited to the requirements peculiar to model aeroplanes. Nothing could be farther from the truth ”

“ Such models are easy to construct, and any one who has built a monoplane will have little difficulty with them. No attempt is made to flex the planes. The cellular type must be equipped with a lifting-plane forward, which may be easily adjusted to any angle, and held in position. It is indispensable that you have two propellers placed aft behind the main plane. The model may be made much more effective by adding a third stability-plane or rudder at the rear. ”

“ The planes of these models are usually made separate from the motor base. The shafts of the propellers, with the rubber motors and skids, are built up in a single piece. This plan has the advantage of making the planes adjustable so that they may move backward or forward as desired. The model leaves the ground from a base, much the same as the rail used by the large Wright machines. Some models are even started by the propulsion of a rubber band attached to the frame, which is pulled back and released, like the old-fashioned sling shot. ”

“ The rubber is so light that it adds little to the weight of the craft. The motor is of course a makeshift and at best only serves to keep the propeller in motion for a fraction of a minute. Experiments have been made in driving the propeller with compressed air, which is carried in an aluminium rod fastened beneath the planes. But the force of thousands of youthful inventive geniuses is certain to bring forth some new motive power.
It is characteristic of the American boy that our young aviators should feel themselves disgraced to fly a model not of their own make. ”

“ Aviation has been reduced to an exact science, but it is yet in its early growth, both in the field of models and in the field of the various kinds of man-carrying machines. Not only are the designers making great headway with aeroplanes, but also with dirigible 127 balloons so any one interested in aeronautics has a very wide field for his work. As we said in an earlier chapter, the boy model designer of to-day may be the inventor of to-morrow who gains undying fame by some now undreamed-of development of the aeroplane. ”

“ The sticks used for the motor base are hollow, being built up of a light veneer one-sixteenth of an inch thick. The joints are so cleverly arranged that they would deceive the average eye. The main sticks of the frame are joined by a series of trusses of the same delicate construction which form an exceptionally rigid base of amazing lightness. Every detail of the model shows the same delicacy of construction. The planes are built up of thin strips of bamboo covered with Japanese silk on both surfaces, the curve being drawn perfectly. ”

“ As a general rule, the biplanes or the models in which the double planes have been used, either for lifting or soaring planes, will settle down more gradually. The lateral planes, whatever their position, also lend valuable support when the critical time comes in the descent. Your model is not perfect until it falls easily at the end of the flight.
Detail of Model Shown in Plate X.
Under perfect condition, in absolutely undisturbed air, an aëroplane may be made to come down so lightly that no bones, even the smallest, will be broken. ”

“ Using the past history of the heavier-than-air machines’ performance and their own experience and the experience of tens of thousands of flyers under all imaginable circumstances and conditions as a basis, they are building various types of aircraft. More than a score of American and British firms have already built and are putting upon the market large numbers of sports models. These machines are single and double seaters after the type of the famous Baby Nieuports, Spads, and British Sopwith Pups. They have a wing spread of anywhere from seventeen to thirty feet. ”

“ An ingenious motor anchorage of metal construction has been hit upon by the builders of model aeroplanes in France. We are all familiar with the difficulty of raising the hook, holding the rubber bands, high enough above the main frame, or fusilage, to be perfectly free. ”

“ Just as one make of motor car can be distinguished from another by noting some characteristic detail, such as the radiator, the trade mark, the hubs, etc., so can the main types of aeroplanes and airships be readily differentiated by the recognition of the outstanding features of each machine. It must be admitted, nevertheless, that it needs considerable experience to be able definitely to classify detail modifications of a particular type of aircraft, for the difference is often very slight. ”

“ Watch the successful model as it gains its altitude, settles down to a horizontal flight, is perhaps knocked off its course by a cross current, and steadies itself with a graceful curve and proceeds on its way.
All these problems must be anticipated. The young aviator must ingeniously arrange his planes and ballast in advance. The regular sky pilot, on the other hand, meets the problems of the air as he encounters them, by flexing his wings against disturbing currents or by banking to maintain an even keel at a turn. ”

“ In other words, model aeroplanes have reached a state of development where they have outgrown the largest indoor enclosures available for flying.
CHAPTER XIV AMONG THE MODEL BUILDERS A number of model aeroplane builders in America have developed distinctive designs which have come to be accepted as standard types. Among thousands of boy amateurs these models are looked upon much as, in the larger field of aeronautics, the Wrights, Curtiss, or Bleriot are accepted as authoritative. ”

“ Two slight vertical rudders, elliptical in form, are carried back of the rear plane. The frame stands in a practically horizontal position. The skids used are very light, touching the ground at a single point. With a six-strand motor the twin propellers are wound about six hundred times. The propellers are broad and of a high pitch. The Easter model clears the ground instantly, rises rather high and makes a beautiful flight. The model shows extremely fine workmanship in every detail. ”

“ If it were not for this arrangement, the ends of the planes in turning would tend to rise, since they travel the faster, and the machine would be in danger of upsetting. The ends of the planes may also be flexed separately when the machine is in straight flight, whenever it becomes necessary to balance it against a dangerous air current or a gust of wind. The pilot, it will be seen, has every point of the great machine, as it were, at his finger ends. ”

“ We have said that the first requisite of a model aeroplane is that it shall fly, but there is no necessity, nor is it indeed always to be desired, that this should be its only one, unless it be built with the express purpose of obtaining a record length of flight. ”

“ Our amateur aviators are attacking one great problem of aviation which the pilots of man-carrying crafts are perhaps neglecting. Model aeroplanes are built to maintain their equilibrium in the air automatically. They must not only rise from the ground, prepared for a long flight, but must be contrived to resist all manner of baffling air currents aloft. ”