124 
Dynamic Pressure, q 
M. P. Tulin 
Gy 20 40 60 80 100 120 
Seacraft Speed in knots Aircraft Speed in knots x 10" 
Propulsion Barrier (Hurdled About 1954) 
upercavitating (Achieved About 1960) ~/\—= 
Subcavitating 
Propulsion Barrier (Hurdled About 1944) 
Supersonic (Achieved About 1950) —‘\/\\> 
Subsonic 
Fig. 2. A comparison of some parameters for seacraft and aircraft 
