Why did the RN in WW2 have open bridges for some vessels?

[Sailor Steve]

Partly tradition, partly necessity.

The first steel battleships had to have open bridges for the simple reason that flying glass was a very real danger, and portholes too small for conducting battle strategies, so the captain (and admiral) had to be where they could see. The bridge was built above the armored conning tower, which housed and protected the helmsman and other crew essential to driving the ship. Between the wars saw the development of armored glass, and by World War Two all battleships had enclosed bridges with big windows. The conning tower behind them was the most heavily armored part of the ship, and the bridge continued to be built from thin plates of mild steel, but that is where the leading officers still had to be because they still couldn't see from the conning tower.

The original Torpedo Boat Destroyers had a small unarmored conning tower, only big enough for the helmsman. The captain stood on the 12pdr gun platform, which was mounted directly on top of the conning tower. The Germans used an actual bridge on their TBDs, which practice was followed by the British 'River' class, but for the reasons given above these continued to be open. World War Two destroyers started to have enclosed bridges, but these were too small for armored glass windows so the officers stood outside unless the weather was bad. True enlosed bridges didn't come to the smaller ships until the 1960s.

[edit]

First I type up a big long post, hit 'Submit' and find that I've been logged out.

So I retype it, with changes, make sure I copy it first and everything is fine.

Then I notice the linked Wiki article.