NO. 3 LANGLE1 MEMOIB ON MECHANICAL FLIGHT 11!) 



extend across from side to side. The top rod is brazed to the side pieces of the 

 hull and the bottom rod to the keel. They are connected by a vertical strut of 

 8-mm. tubing at a distance of 265 mm. inside of each propeller shaft. At the 

 front end of the propeller shaft two more rods run across the frame. The lower 

 is similar and parallel to the back rod already described, while the upper is bowed 

 to the front, as shown in the plan view of the frame (Plate 30). In order to 

 take the forward thrust of the propeller a second cross-brace is inserted, which 

 runs from the rear bearing of the propeller shaft to a point just in advance of 

 the front head of the cylinder, and is brazed to the two upper tubes of the cross- 

 frame as well as to the upper tubes of the main framing of the hull. The outer 

 ends of the tubes of the cross-framing are brazed to a thin, stamped steel plate 

 which firmly binds them together, while at the same time it forms a base for 

 attaching the bearings of the propeller shaft. This end plate has a thickness of 

 one millimetre. 



In addition to the framing proper there are two guy-posts which fit into 

 the sockets CC, and over which truss wires are drawn, as shown in the side view 

 in Plate 27A. These posts have a length of 730 mm. from the lower edge of the 

 socket, and are capped at their lower extremity by a light steel ferrule whose 

 outside diameter is 10 mm. 



From the drawing of the wings of No. 5, shown in Plate 17, it will be seen 

 that they are formed of two pine rods 15 mm. in diameter at the inner ends, ta- 

 pering to a half circle of the same diameter at the tips. These rods are con- 

 nected by eleven spruce ribs measuring 8 mm. x 3 mm., and curved, as shown in 

 the side elevation, these, in turn, being covered by a light white silk drawn so 

 tightly as to present a smooth, even surface. The total length of the wing is 2 

 metres, and the width over all is 805 mm. Vertical stiffness is obtained in the 

 wings by a series of guy-wires, which pass over light struts resting upon the 

 main rods. These main rods are inserted and held in the wing clamps A and B, 

 Fig. 16, and make an angle of 150° with each other. As is the case with all 

 other essential details of the aerodrome, a great deal of time and attention was 

 given to the designing of the wing clamps before a satisfactory arrangement 

 was secured. 



To enable it to control the aerodrome in both directions, the tail-rudder, 

 Plate 27A, has both a horizontal and a vertical surface, the approximate dimen- 

 sions of which are, length 115cm. (3.8 feet), maximum width 64 cm. (2.1 feet), 

 giving each quarter section an area of about 0.64 sq. m. (6.9 sq. ft.). It is given 

 the proper angle and degree of elasticity in a vertical direction by the flat hick- 

 ory spring, which fits into the clamp N, and attaches the rudder to the frame. 



The only other attachments of the aerodrome are the reel, float, and counter. 

 They have nothing whatever to do with the flying of the machine, and are 



