 The DNC prepared two new designs in response to Admiral Jellicoe 's comments on 1 February 1916 , each for a battlecruiser capable of thirty knots or better and armed with eight 15 @-@ inch ( 381 mm ) guns . Design ' 1' displaced 39 @,@ 000 long tons ( 39 @,@ 626 t ) with two less inches in belt armour and a speed of thirty knots . It used the bulky large @-@ tube boilers traditional in British capital ships , which explains why the design was 9 @,@ 000 long tons ( 9 @,@ 144 t ) larger than any of the previous battleship designs . Design ' 2' was essentially a repeat of the first design except that small @-@ tube boilers were substituted . These were considerably smaller than the older type and saved 3 @,@ 500 long tons ( 3 @,@ 556 t ) over Design ' 1' and had one less foot of draught . These savings were substantial enough to overcome the Engineer @-@ in @-@ Chief 's objections that they required more frequent and expensive repairs . The DNC was asked to submit four more designs using small @-@ tube boilers which were submitted on 17 February . Design ' 3' was Design ' 2' with the machinery power increased to 160 @,@ 000 shaft horsepower ( 120 @,@ 000 kW ) to boost the maximum speed to 32 knots ( 59 km / h ; 37 mph ) while the other designs had either four , six or eight 18 @-@ inch ( 457 mm ) guns . Design ' 3' was selected as Admiral Jellicoe has specified that the minimum number of guns should be no less than eight as fewer caused problems in accurate fire control , and two alternatives were to be provided , one with a dozen 5 @.@ 5 @-@ inch guns and the other with sixteen such guns . The latter proposal was selected on 7 April and orders were placed on 19 April for three ships ( Hood , Howe and Rodney ) . The order for the fourth ship , Anson , was placed on 13 June . 
