 The ships would have been equipped with four sets of steam turbines rated at 80 @,@ 000 shaft horsepower ( 60 @,@ 000 kW ) powered by fifty @-@ two coal @-@ fired Belleville boilers . Each propeller shaft was connected to a high @-@ pressure turbine , a medium @-@ pressure geared turbine , and a low @-@ pressure turbine for forward steaming , and a direct drive turbine for steaming in reverse . The ships ' top speed was to have been 28 knots . The ships would have been supplied with 2 @,@ 833 t ( 2 @,@ 788 long tons ; 3 @,@ 123 short tons ) of coal and 630 t ( 620 long tons ; 690 short tons ) of fuel oil for supplementary oil firing . At maximum speed , the ships could have cruised for 1 @,@ 660 nautical miles ( 3 @,@ 070 km ; 1 @,@ 910 mi ) ; at 20 @.@ 3 kn ( 37 @.@ 6 km / h ; 23 @.@ 4 mph ) , the range increased to 4 @,@ 240 nmi ( 7 @,@ 850 km ; 4 @,@ 880 mi ) , an at a more economical 15 kn ( 28 km / h ; 17 mph ) , the range grew to 6 @,@ 300 nmi ( 11 @,@ 700 km ; 7 @,@ 200 mi ) . 
