TAKIXG Ol-'l' OF AEKOPLAXl-:,S. '-343 



Table YI. 



Vickers-Yimy. Heavy load. Total weight = 11,000 lbs. Rate 



of climb ill feet per iniiiute : at sea-level, 523 feet per uiimite. 



For jiiirposes of comparison Ave may take the results 

 for tlivi D.II.9 machine with the Siddeley Puma engine 

 (" Yoortrekker "). The loading' is taken as follows: — 



Machine, light ... ... ... 2,200 



Fuel and oil ... ... ... 500 



Crew, etc. ... ... ... ... 300 



Total weio-ht 



3,000 lbs. 



Wing- area, 43(j s(|uare feet. Revolutions per minnte, 

 1,350. Horse power (sea-level), 242. Horse power per 

 1,000 lbs., 79' 1. Wing'-loading-, T lbs. per sqnare foot. 



TviiLE A^II. 



" Yoortrekker." Rate of climb in feet per minute: 

 at sea-level, 905 feet per minnte-. 



It will be seen tliat the rate of climb of tlie Yickers 

 machine k)aded i,s it left IJulawayo falls to a very low value 

 for liig-h altitudes and high temperatures. Taking the 



