Johnson, Jr. 

 REFERENCES 



1. Brandau, John H., "Aspects of Performance Evaluation of Water jet Propul- 

 sion Systems and A Critical Review of The State -of -the -Art," Journal of 

 Hydronautics (AIAA), April 1968. 



2. Johnson, V.E., Jr., "Waterjet Propulsion for High-Speed Hydrofoil Craft," 

 AIAA, Journal of Aircraft, March-April 1966. 



3. Traskel, J., and Beck, W.E., "Waterjet Propulsion for Marine Vehicles," 

 AIAA Journal of Aircraft, March-April 1966. 



4. Arcand, L., and Comolli, C.R., "Waterjet Propulsion for High-Speed Ships," 

 AIAA/SNAME Advanced Marine Vehicles Meeting, Paper No. 67-350, May 

 1967. 



5. Hsieh, T., "Linearized Theory for a Two -Dimensional, Base-Vented Strut 

 with an Inlet in the Leading Edge," Hydronautics, Inc. Technical Report 

 463-8, Nov. 1966. 



6. Contractor, D.C., "Experimental Investigation of a Water Jet Propulsion 

 System for Shallow Draft Boats," Hydronautics, Inc. Technical Report 

 516-a, May 1966. 



DISCUSSION 



Pier Giacomo Maioli and Giovanni Venturini 



Ministero Difesa Marina 



Rome, Italy 



In a recent paper we have prepared with Cdr. Maioli, we have tried to work 

 out an expression of what we called "total propulsive efficiency," defined as the 

 ratio of the effective horsepower of a "basic" hull and the brake power of the 

 primary mover. The basic hull is an ideal hull, complete in every part with the 

 exception of its propulsive devices and those parts which are connected to the 

 propulsive devices. 



If the missing parts are added, though the value of design speed is kept the 

 same, hull resistance increases, both because of the increase in weight and be- 

 cause of the presence of additional elements in the water. 



In this way external efficiency may be defined as the ratio between the re- 

 sistance of the basic hull and the resistance of the complete hull. 



1054 



