The firing-arc penalty of Nelson's compressed turret arrangement

Earlier studies offered arrangements that spread the secondary guns more effectively around the ship. The final design was made as short and compact as possible, concentrating the main battery and moving the secondaries aft. Blast from B turret firing too far abaft the beam could break bridge windows and send glass through the command spaces, so the broad theoretical arc was undesirable outside an emergency. The Royal Navy later improved the bridge protection, but crews still preferred not to use that firing position. The limitation shows how treaty displacement pressure affected practical weapon arcs and topside layout, not only armour thickness and speed.