212 



ANNUAL REPORT SMITHSONIAN INSTITUTION, 1950 



FURTHER EXPERIMENTS THROUGH 1901 



Encouraged by their first year's experiments, the Wrights designed 

 and built a larger glider (pi. 1, fig. 2) late in the spring of 1901, with 

 the express purpose of improving the performance as a man-carrying 

 kite so that many hours of control experience could be built up at 

 minimum risk. To this end, the new craft had a wing spread of 22 

 feet, a total area of 290 square feet, and a rib section that had a camber 

 ratio of 1/12, to conform more closely to Lilienthal's tables. The 

 new elevator was proportionately larger and was controlled by deflect- 

 ing its trailing edge. Apparently, the wing warp was controlled in 

 the same manner as in the earlier glider. 



The equivalent monoplane aspect ratio of the new machine was 2.9 

 as compared with 2.87 for the first year. The structure weight was 



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lO/lreAJ 



108 pounds ; thus, the new wing loading was 0.37 pound per square 

 foot, against 0.32 pound per square foot for the earlier machine. 



From the first trials of the machine, as a glider, it was soon apparent 

 that the new wing curve induced pitching moments that were beyond 

 the capacity of the front elevator to balance. They were able to avoid 

 disastrous stalls and dives only by shifting their body weight. By 

 removing the upper wing and restraining it in a high wind, they 

 were able to lay the trouble to center-of-pressure travel and to re- 

 capture the more stable performance of the first year's craft by trus- 

 sing down the ribs to a lesser camber. 



