NO. 3 LANGLEY MEMOES ON MEOHANK \l. FLIGHT L93 



Wing. 



" Single-tier " 4.27 



Superposed. Type No. 2 4.27 



The " single-tier " wings actually used on Aerodrome No. 6 were 5.33 feet 

 long, while the wing tested above was only 4.27 feet long. In order to bring out 

 more fully what might be expected of Aerodrome No. 6, when using the two 

 different types of wings, the following table, calculated from the preceding 

 one, is given. This shows the results which might be expected from the aero- 

 drome when the resistance of the machine itself was included: 



Aerodrome No. 6 without wings weighs 22 pounds. 



a> ^ 2 :? . a 3 9 .?: vS- -~ c-Sqj ! — >^n^5 sx o w -flee hou 



"Single-tier" (short) 4.27 44.8 5.04 27.04 0.603 6.06 1.0 7.06 27.0 0.35 .70 



" Single-tier " (full length) 5.30 54.0 5.5 27.5 0.51 6.13 1.0 7.13 24.7 0.32 .64 

 Superposed. Type No. 2. 4.27 87.6 10.36 32.36 0.369 6.9 1.0 7.9 25.3 0.364 .73 



The first line shows the calculations for the aerodrome when equipped with 

 the short " single-tier " wings; the second line, when equipped with the " single- 

 tier " wings of the full length used in the flights of 1896; and the third line, 

 when equipped with superposed wings, Type No. 2. 



It will be seen that, on the whole, the result of the comparison of the full- 

 length " single-tier " wing and the superposed one is less in favor of the latter 

 than was to be expected, as, aside from its greater structural strength, it seems 

 to have no real point of superiority, except that it is shorter; and, as already 

 pointed out, one point of presumable inferiority, though not exhibited in the 

 table, is the fact that the rear set of wings would suffer relatively more from 

 being in the lee of the front ones, in the case of the superposed wings, than in 

 the case of the " single-tier " ones. 



Besides these " conventional " forms of wings, various oilier types were 

 tested on the whirling-table. The data of these tests are no1 given, as in the 

 rough preliminary tests the results were so entirely negative in character that 

 accurate quantitative tests were never made. However, since in work of this 

 kind the greatest delay is experienced in learning wliat not to do, and in rid- 

 ding one's self of freak notions which are continually suggesting themselves, it. 

 may be well here to describe sufficiently at leas! one of these types of wing to 

 enable others to avoid any loss of time in experiments with it. Since the prin- 

 cipal disadvantages of a win^ possessing considerable width in the fore and 

 aft direction are due tc the great extent through which the center of pressure 



