 The ships were also armed with six 45 cm ( 17 @.@ 7 in ) torpedo tubes , all in above @-@ water swivel mounts . Four tubes were mounted on the sides of the ship , another in the bow , and the last in the stern . These weapons were 5 @.@ 1 m ( 201 in ) long and carried an 87 @.@ 5 kg ( 193 lb ) TNT warhead . They could be set at two speeds for different ranges . At 26 knots ( 48 km / h ; 30 mph ) , the torpedoes had a range of 800 m ( 870 yd ) . At an increased speed of 32 knots ( 59 km / h ; 37 mph ) , the range was reduced to 500 m ( 550 yb ) . 
