 Above the armored deck , Yorktown had forecastle and poop decks with an open gun deck that spanned the length of the ship between them . The conning tower was located forward on the forecastle deck and was oval @-@ shaped to deflect shot . It was outfitted with a steam @-@ powered steering wheel , an telegraph , and speaking tubes ; it was protected by 2 inches ( 51 mm ) of steel armor plate . 
