PLATE V.
Too Large for Beginners, but Will Make Long Flights.
The narrow-prowed form of this model is also very interesting and its principle may well be copied. 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.
In the present state of model aëroplane building, the longest flights are made with an adaptation of the monoplane forms. An excellent model is shown in [Plate 10]. The dihedral, or V shape of the planes gives them greater supporting power than others in the horizontal position. The stability plane beneath is particularly recommended, since it utilizes the frame already in position and does not add to the weight of the model. The rear of this plane, which is hinged, is easily adjusted.
The planes of this model are especially interesting. They are made of silk, laid over frames of dowel sticks, and each pair is held tightly together by the simple device of connecting them with elastic bands, attached to clasps. The wires running to the corners of the planes, are fastened to small brass rings which may be slipped over the sticks or posts in the center of the frame, which makes them very simple to adjust. It will be noticed that the rear part of each plane swings freely, and is kept in place only by corset steels, used as ribs, which are sewn into the cloth. These floating or soaring blades, as they are sometimes called, insure longer flights.
With such a model there is little danger of building a too powerful motor. By increasing the size of the wings, and careful weighting, a surprising amount of power may be applied to such a model without rendering it unstable. This is of course a great advantage in such a model, since it lends itself to longer flights and the installation of comparatively heavy motors. When you find yourself with a model of this design in good working order, experiment by binding the wings or planes at the middle to form an arched surface like the wings of a sea gull. The flying radius of some of these models has been increased fully fifty per cent by this simple expedient.
An interesting modification of this form ([Plate 11]) is provided with rigid wings, and is driven by a single propeller. The very simple but effective method of bracing the wings, may be studied to advantage. The skids are well designed. In still another type of this general monoplane form ([Plate 12]) the propeller is placed in front of the planes, and the rubber motor runs below the main bar. The wheels supporting this model are particularly well made.
A very serviceable, little monoplane form may be made by making the rear upper plane adjustable (Plates [13]-[14]). The front plane is V-shaped and is unusually stable for so light a model. By tilting the rear plane up or down, a good level flight may be obtained. The frame, in this case, is made of wire. The propeller is placed well behind the rear plane, thus bringing the center of gravity well forward to balance the angle of the rear plane. The blades of the propeller are made of twisted wood, which is not to be recommended, since it is likely to lose its shape.
In Plates [15]-[16] we have a well thought out little monoplane, which well repays study. The propeller is set forward of the lifting plane which is the larger of the wings. The rear plane may be tilted up or down. The rudder, which is also adjustable, is set below it. The arrangement of skids is excellent, enabling it to rise from the ground with little loss of friction. The method of flexing the front plane may well be imitated.