Page:Popular Science Monthly Volume 92.djvu/74

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��Popular Science Monthly

��This adds to the strength of the entire biplane.

But the Germans have improved upon the Nieuport in this: They have spread the central struts which hold the upper wing to the fuselage or body, far apart. Hence the two wings are tied together by only two sets of struts — the triangular ones previously described and the central ones. Why was this done? Simply to avoid the use of wires. In the older ma- chines, by which I mean machines that flew in the early weeks of the war, there were a far greater number of wires than would now be considered permissible. Wire bracing extended in all directions. Now, a piano wire which vibrates a distance of half an inch to either side of its normal position offers as much re- sistance as a rod one inch in diameter. A wire may seem thin, but when it vibrates it is the equivalent of a thick rod. It offers much resistance as a result. And so we find the airplane designers of the world trying to get rid of wires. The builders of the Albatross have gone far in this direction.

From the British, the Germans copied the rounded outline of the tail fins. The tail surfaces of a flying machine have much the same effect as the feathers of an arrow. They steady the machine. The perfect target arrow has rounded feathers. This explains the British tail formation of the German Albatross.

More than any other lighting machine thus far designed the Albatross is shorn of projections. Indeed, the craft ap- proaches a bird in cleanness of line. The water tank, for instance, is no longer found near the engine; it is built into the upper wing. The radiators, through which the GGCling water circulates, lie flat against the fuselage or botiy.

Steadying fins and rudders and ailerons (the hinged surfaces at the rear corners of the upper wing, serving to balance the machine from side to side) must be strong and stiff and yet free from external sup- port. But their wind resistance must be low. The Germans met the situation by giving the fins and rudders a stream- line form, which means a shape that parts the air most easily. The steadying effect of a fin depends in part on its area. Additional area was gained very cheaj)ly by filling out the space between the fuse- lage or body and the tail-skid.

��The fuselage or body in which the single fighter sits is noticeably large. But mark the lines. This smooth, correctly de- signed bulk, large as it is, parts the air with the lowest possible resistance. Note how the fuselage and the wings are tied together so as to get rid of struts and wires. The idea is not new, but it has been so ingeniously carried out that it deserves mention here.

The exhaust from the engine is care- fully collected and conducted downv/ard and rearward. Whiffs of exhaust gaa should not be added to the tribulations the pilot already has to bear.

It takes a certain amount of muscular effort to swing a rudder quickly. Clearly, the fighter who can swing his rudder most quickly has the greatest maneuvering ability. The muscular effort involved, must not retard a man from making the right turn at the right moment. Hence we find that in the Albatross all the con- trolled surfaces are balanced, which means that triangular extensions are provided beyond their pivots. You will find this clearly brought out in the tail of the Albatross as it is shown in the accompany- ing drawing.

Since the entire machine must be swung around in order to aim a gun, it is obvious that as many as twelve guns could be mounted if there were place for them. Indeed, on the Nieuport as many as five have been carried — three on the upper wing and two firing through the propeller. No doubt a similar practice is followed by the Germans. In our drawing we have shown only two machine guns firing through the propeller.

How astonishing it is to find the in- ventions of fairy-tale writers brought to rsalization. For years we have been en- tertaining our children witi^ cc oi the most beautiful fairy-tales of Hans Chris- tian Anderson — a tale in which a wicked prince rashly essays to fight God himself with ships flying through the air and mounting guns that rain thousands of bullets in response to the mere pressing of a button. Look at the Albatross and you will see the magical l)uttons attached to the control-lever. Who knows but flying machine designers may find other improvements suggested in what we have been pleased to consider the poetic vaporings of romancers!

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