 The Lexingtons were included as part of the Naval Act of 1916 . Like the South Dakota @-@ class battleships also included in the 1916 Act , their construction was repeatedly postponed in favor of escort ships and anti @-@ submarine vessels . During these delays , the class was redesigned several times ; they were originally designed to mount ten 14 @-@ inch guns and eighteen five @-@ inch guns on a hull with a maximum speed of 35 knots ( 65 km / h ; 40 mph ) , but by the time of the definitive design , these specifications had been altered to eight 16 @-@ inch guns and sixteen six @-@ inch guns , with a speed of 33 @.@ 25 knots ( 61 @.@ 58 km / h ; 38 @.@ 26 mph ) to improve hitting power and armor ( the decrease in speed was mostly attributed to the additions of armor ) . 
