A successor armed with eight 15-inch guns threatened to exceed the dimensions of France's existing yards and docks. Developing another new gun would also be expensive after the 340 mm weapon had equipped only the Bretagne class. Normandie therefore sought comparable firepower through twelve smaller guns in quadruple turrets. The choice has a parallel in the American decision to increase the number of 14-inch guns when a 16-inch weapon was refused. Lyon extended the idea to sixteen 340 mm guns, but its expected contemporaries would be protected against 14-, 15-, or possibly 16-inch fire. Retaining the existing calibre reduced development demands while making penetration of newer protection increasingly doubtful.
Notable Point · 9:08-14:55
Normandie and Lyon stretched France's investment in 340 mm guns
Restricted yards and a short production run encouraged France to retain 340 mm guns, first in twelve-gun Normandie and then in sixteen-gun Lyon.