Fully Cavitating Propeller for a Hydrofoil Ship 



INBOARD G'BOX 



CONTROLLABLE 

 PITCH 



SUPERCAVITATING 



OUTBOARD G'BOX 



Fig. Z - Layout of propulsion system 



Table 1 

 Principal Specifications of the Bras d'Or 



Length: 150 ft-9 in, Hull Beam: 21 ft-6 in, Foil Span: 66 ft 



Weight: 200-250 tons (according to fuel carried) 



Speed: Foilborne - 60 knots, calm water 

 50 knots, sea state 5 



Range: Several hundred miles foilborne. 



More than 2000 miles at 12 knots huUborne. 



Power: Foilborne - P & W FT 4 gas turbine, 25,000 shp continuous. 

 Driving two fully cavitating propellers. 



Hullborne - Davy Paxman 16 YJCM diesel, 2000 bhp continuous. 

 Driving two controllable pitch propellers of KMW 

 design. 



The power transmission system for the fully cavitating propellers has been 

 developed by the General Electric Company of the USA, the pioneer of hydrofoil 

 'Z' drives. The power output from the turbine passes into an inboard gearbox 

 where the speed is increased from 4000 rpm maximum to 8000 rpm, to reduce 

 the torque and hence shaft diameters to fit within the struts. The main drive is 



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