Pallabazzer 



Fig. 30 - IR-(2) \^ performances: (a) ^i = 

 0.9; (b) V = 0.7 (p = 12, a. p.) 



It is also remarkable that the effect of the valve losses S/3 is very 

 small on the performances, but it is large on the operating limits, because at 

 increasing S/3 the maximum speed which can be operated decreases. Besides, 

 in terms of efficiency, the decrease of i// from 0.9 to 0.7 which has been tried 

 is quite unfavorable. 



(b) The cold-air bypass powerplant (Figs. (31), (42)] appeared to be 

 very ineffective from any point of view: The specific thrust can be two or 

 three times less than for a hot-gas hydrojector, the efficiency about two times 

 less, and the inflow ratio also about two times higher. These parameters are 

 very poor also when compared with the water jet's ones. 



The overall efficiency is too low to permit economically convenient 

 running, and the thrust could propel just a proportionately light vehicle. It is 



1150 



