56 THE NAVY OCEAN ENGINEERING PROGRAM 



The design of the nonpropulsion machinery systems for deep vehicles 

 which places emphasis on Ughtweight, high-performance systems is the 

 same. At the start of most deep vehicle design efforts, many of the per- 

 formance requirements are not firm. Each system must be investigated 

 over a wide range of possible design goals. The development of such infor- 

 mation requires a much more detailed analysis of the systems than nor- 

 mally is required for large-ship preliminary designs. Shortcut methods of 

 estimating weights and performance of systems are not adequate to pro- 

 vide the precise weight, space, and performance data essential for small 

 deep vehicle designers. Conventional large submarine approaches to the 

 problems of heating, cooHng, and atmosphere control are often not feasi- 

 ble due to the extreme space and weight limitations. As such, the actual 

 endurance of many deep vehicles is limited by these life support systems. 



Electric Motors 



Applications for undersea motors include mechanical power for con- 

 struction machines and mechanical power for vehicle and fixed installa- 

 tions. The electric power sources available for use on small deep- 

 submergence vehicles are direct current sources. In order to eliminate 

 shaft penetrations, decrease the size of pressure spheres, and increase 

 buoyancy, the propulsion and thruster motors can be mounted exterior 

 to the pressure huU. The motors are subjected to full submergence 

 pressure. Most of the motors being used in deep submergence appUca- 

 tions are dc, oil-immersed, pressure-compensated motors. These motors 

 have not been satisfactory because of brush wear, brush arcing, and oil 

 carbonization. In addition, contamination of oil by sea water may render 

 dc motors inoperative. 



A Navy contract has been awarded to design, construct, and test a 

 prototype ac system for the DSRV. The system wiU include pressure- 

 compensated ac motors and inverter/controllers for each of the motors. 

 The contract provides for purchase of one 15 HP propulsion motor, two 

 T/i HP hydraulic motors, four Th HP thruster motors, and the inverter 

 controllers for each of the motors. 



A contract has also been let to construct and evaluate a feasibility 

 model of a "Nadyne" propulsion motor and converter unit suitable for 

 use on deep submergence vehicles. These motors are ac but promise good 

 speed regulation. 



