 The first ocean @-@ going ironclads carried masts and sails like their wooden predecessors , and these features were only gradually abandoned . Early steam engines were inefficient ; the wooden steam fleet of the Royal Navy could only carry " 5 to 9 days coal " , and the situation was similar with the early ironclads . Warrior also illustrates two design features which aided hybrid propulsion ; she had retractable screws to reduce drag while under sail ( though in practice the steam engine was run at a low throttle ) , and a telescopic funnel which could be folded down to the deck level . 
 The first ocean @-@ going ironclads carried masts and sails like their wooden predecessors , and these features <a href='uninflect' title='1'><mark>were</mark></a> only gradually abandoned . Early steam engines <a href='uninflect' title='2'><mark>were</mark></a> inefficient ; the wooden steam fleet of the Royal Navy could only carry " 5 to 9 days coal " , and the situation was similar with the early ironclads . Warrior also <a href='uninflect' title='3'><mark>illustrates</mark></a> two design features which aided hybrid propulsion ; she had retractable screws to reduce drag while under sail ( though in practice the steam engine was run at a low throttle ) , and a telescopic funnel which could be folded down to the deck level . 
The first ocean @-@ goin ironclads carried masts and sails like their wooden predecessors , and these features was only gradually abandoned . Early steam engines was inefficient ; da wooden steam fleet of tdaRoyal Navy could only carry " 5 to 9 days coal " , and the situation was similar with the early ironclads . Warrior also illustrate two design features which aided hybrid propulsion ; she had retractable screws to reduce drag while under sail ( though in practice the steam engine was run at a low throttle ) , and a telescopic funnel which could be folded downn to the deck level .