432 ANNUAL REPORT SMITHSONIAN INSTITUTION, 194 7 



£00 300 400 soo eoo too 



TRUE AIRSPEED-MRH. 



FiGXJEE 1. — Thrust vs. air speed at sea level. 



200 



600 



TOO 



300 400 SOO 



TRUE AIRSPEED- M.RH. 



FiGUBE 2.— Thrust vs. air speed at 20,000 feet. 



Outstanding is the rocket's complete superiority in performance at 

 high altitudes where airplane drag is greatly reduced. Thus, high- 

 altitude speeds will necessarily be outstanding as will also the high 

 rate of climb at all altitudes. 



Eelatively constant thrust with speed variation is also apparent for 

 the turbojet. In this case output suffers considerably with altitude, 



