All the best models this year are equipped with twin propellers. It is very little more trouble to build two motors than one, and the model thus equipped will not only travel much further, but will insure much more stable flights. A common trouble in model building has been the lack of stability. Your model has been likely to capsize, even under favorable conditions, spoiling the flight, while a chance gust of wind would knock it out of its course in spite of everything you could do. To overcome this tendency, the surface of the planes might be increased, but this added to the weight of the model, thus cutting down the length of the flights. The twin propellers cut at the root of the problem. They balance the thrust, thus making the flight even and stable. The planes may also be made much smaller with a gain in weight which, in turn, lengthens the flight. [Illustration: A variation on a familiar form.] [Illustration: An excellent model designed and built by H. Wakkins.] CHAPTER II MODEL AEROPLANE TOURNAMENTS Within the year, exhibitions and contests of model aeroplane flights have become an established form of entertainment. The attractions of the flights of man-carrying machines are borrowed in a large measure by the model aeroplanes. The building of models has progressed so rapidly, bringing the little air-craft under such control, that a definite program of flights may now be carried out. The programs may be considerably varied to include distance flights, weight-lifting contests, and spectacular flights in which the models loop the loop and perform other amazing feats. The first formal exhibition or professional appearance of the model aeroplane in public as an entertainment was made in connection with the first aviation meet held at Asbury Park, New Jersey. Two of the most successful model builders, Percy Pierce and Frank Schoeber, of the New York Model Aero Club, were engaged to give exhibition flights for one hour a day in the intervals between the flights of Arch Hoxey, Johnston and other aviators of the Wright Brothers staff. [Illustration: An original design by Harry McAllister] [Illustration: An interesting experiment in stability] [Illustration: An early model built by E.G. Halpine] The models were flown for more than 200 feet and were enthusiastically applauded. The aeroplanes in miniature imitated the flights of the man-carrying craft with wonderful fidelity, rising from the ground and soaring aloft in long, graceful curves. They came as a very welcome variety, and could be watched without breaking one’s neck gazing aloft, or the unpleasant possibility of a serious accident. The applause of the thousands gathered for the meet may be said to have definitely established the model aeroplane as a feature of these tournaments.