History of the Admiral Class

In 1914-15, operations of the Royal Navy under wartime conditions highlighted some flaws in its capital ships. One major problem that failed to materialize in peacetime was low freeboard. Under war conditions, ships went to sea more heavily loaded, causing the ships to sit lower in the water. This caused not only wetness and discomfort to the crews, but often made secondary guns unworkable as seas washed over the decks and into the casemates. A related problem was that the deeper the draft of the ship was, the more water pressure there was along it, and the more the ship would flood if damaged. Underwater protection against torpedoes and mines would need to be improved also.
In 1915, the Navy obtained funds to build an experimental battleship of reduced draft, with high freeboard and a secondary battery high above the water. Five designs were drawn up, using armament and machinery from the Queen Elizabeth Class battleships. When submitted for review to Admiral Jelicoe, C in C of the Grand Fleet, all were rejected. Jelicoe felt he had enough battleships, but was in need of fast battlecruisers to match 30-knot, 15' gunned vessels believed to be building in Germany.
The designers went back to work, reducing the armor, lengthening the hull, and adopting small-tube boilers, all to increase speed. The preliminary design was approved on 7 April 1916, and three ships were ordered that day. A fourth ship was ordered in July.
Official Admiralty documents claim that the Hood was laid down on May 31, 1916, the day before the battle of Jutland. However, shipyard records do not indicate that any work on the ship was actually done on that day. Either way, any gathered materials were diverted to other projects, and work on Hood and her sisters was immediately suspended while the battle was investigated.
The lessons of Jutland led to several redesigns with increased protection, and the ship was laid down again on September 1, 1916. The new design was almost 5000 tons heavier than the original, and sat 3 feet deeper in the water. To make up for the lost freeboard, sheer was added aft. More equipment, torpedo tubes, and other modifications during construction increased displacement even more. Her quarterdeck was often awash, but other than being very wet she was a good sea boat.
Hood's three sisters were cancelled outright in favor of more advanced designs. Hood was modified on the slipway again in 1918, and twice in 1919. The resulting ship was an impressive beauty, with long graceful lines, impressive firepower, and great speed. Hood was clearly an advance over the preceding Renown, with small tube boilers, extra firepower, more armor, and a main belt sloped to increase resistance to long-range fire. She was the world's largest warship, the fastest capital ship in the Fleet, and was the pride of the Royal Navy.
Protection, however, left much to be desired. It was fairly advanced by the 1915 standards she was designed to, but by the time she was completed in 1920 she could not be considered modern. The main belt was thinner than contemporary battleships, and the thick part of the belt was rather narrow. With each modification to her design, and with each piece of equipment added during a refit, the thick part of the belt slipped lower and lower into the water. The horizontal protection was quite thin, and in places where it was thickened during construction additional protective plates were laminated over existing plates, a solution that gave less protection than a single thickness of armor plate. While changes to her protection during construction helped, she was too far advanced in building to full incorporate the lessons of the First World War. Even as Hood was completed it was known that her protection was not up to modern standards, and several times over her life span it was proposed to rebuild her. But financial restrictions, and the greater need to rebuild older vessels, caused this rebuild to be postponed until 1942, but the war assured that no rebuild would ever happen.
Many publications, such a Jane's, list Hood as a battleship, and she is often sighted as the first fast battleship. However, she was listed by the Royal Navy as a battlecruiser. Her construction, like all British battlecruisers, was one deck lower than all British battleships. She was the largest, most powerful, best protected battlecruiser ever completed by any nation. But like the battlecruisers before her, her protection did not allow her to fight enemy battleships.

Hood:

1923-24 World cruise
1929-31 Refit, catapult added
Sep 1931 Part of crew mutinied at Invergordon
23 Jan 1935 Collided with Renown in Atlantic
1936-38 Spanish Civil War Neutrality Patrol
20 Sep 1938 Ran aground off Gibralter
1939 Refit, AA increased submerged TT removed.

WWII Service:
Aug 1939- Mar 1940 Home Fleet
26 Sep 1939 Hit by German aircraft bombs, minor damage
Mar - May 1940 Refit, AA increased catapult removed
Jun - Aug 1940 Force H, Gibraltar
3 Jul 1940 Bombarded French Fleet at Mers-el-Kibir
Fired 56 shells, stripped turbine trying to catch Strasbourg
Spring 1940 Radar installed
21 May 1941 Sailed to intecept Bismarck with Pronce of Wales
24 May 1941 Destroyed Battle of Denmark Strait by magazine explosion
1,415* killed, 3 survivors
Wreck discovered 63-22 N 032-17W
20 Jul 2001
Thanks to Frank Allen of the HMS Hood Association for this corrected casualty figure. Most sources list 1,416 as the number, but the Association has confirmed that one crewman listed in Admiralty records as KIA on Hood was actually killed on board HMS Prince of Wales during the same battle.