Navies specify armour by weight over an area, such as pounds per square foot, because its weight and position affect the ship's stability. Thickness is an easier way for a general audience to picture the plate. Denser, better armour takes up less space, while its placement affects the centre of gravity and metacentric height. Manufacturers resist paying for trials that cost money and could expose faults in their own armour. A separate Admiralty research budget would let the Navy conduct firing tests with its own guns and plates. Earlier testing could improve shell performance, armour quality and ship design before the First World War.
Notable Point · 53:42-1:00:05
Armour weight, stability and independent shell trials
Navies design armour around weight and protection, while independent shell-and-plate trials could expose problems before a war tests them.