Onrushing Technological Advances Open a Capability Gap
The launch of the Dreadnought in the early twentieth century is held by naval historians to be a revolutionary advancement in naval technology, and led to a naval arms race between the world's great naval powers – the United Kingdom, United States, Imperial Germany, and Japan (plus to a lesser extent France, Russia, and Italy) – that saw construction of dozens of powerful new battleships, nicknamed dreadnoughts in honor of the ship that began this race.
But the Dreadnought's salient features – all large gun armament, broadside weight and armor as the priorities – brought about a major gap between the capabilities of this new standard in capital ship design and the next largest oceangoing class of warships, the armored cruisers. Several of these navies began to look at the possibility of filling this gap with a capital ship that emphasized speed and armament over protection; thus was the battlecruiser concept born.
The Battlecruiser – a Distinct Type with an Indistinct Definition
What constitutes a battlecruiser has never been fully decided. Each navy created its own designs meant to fulfill specific roles, and naturally sought to build vessels that would compete with their potential adversaries' designs. However, certain salient features were common to most battlecruiser designs.
They were meant to be faster than battleships/dreadnoughts, and better armed than the largest armored cruisers – later known as heavy cruisers – which usually mounted eight or nine inch guns. They were expected to hunt down armored cruisers sent on open ocean commerce raids, and engage the cruiser screens that accompanied battleship fleets as scouts. In any situation where they were outgunned they were expected to simply move out of range.
Of course within these roles there was significant specialization- depending on the navy doing the design work. The Royal Navy particularly emphasized speed and armament, often building battlecruisers that were armed with guns as large as those mounted by battleships. They sacrificed armor in order to increase their speed, but this was judged to be acceptable as they were not supposed to engage opposing battleships in a fleet battle. The Imperial German Navy, on the other hand, favored battlecruisers that could survive an engagement with opposing battleships. They tended to sacrifice gun armament for speed rather than armor, which was sensible considering that German capital ships were generally going to be outnumbered in battle.
Jutland Losses: the Royal Navy’s Battlecruiser Force Decimated
The Battle of Jutland occurred as Germany sought to break the Royal Navy imposed blockade of its North Sea ports. Germany was fighting enemies on two fronts and its civil industry was running short of needed supplies. Although the High Seas Fleet was inferior in size to the Grand Fleet of the Royal Navy, an attempt to break the blockade was judged vital to the war effort.
During a previous battle, the Germans experienced a near-fatal attack on one of their battlecruisers that revealed a dangerous quirk in the armor protection scheme employed by most battlecruisers. Their weaker armor could allow a penetrating strike on a major gun turret, and this could result in the explosive detonation of the vessel's primary magazine. The afflicted German vessel survived through luck and skill, and the Germans made efforts to mitigate this danger.
The British had no such knowledge, and at Jutland they paid dearly. Admiral Hipper of the German battlecruiser detachment managed to lure his British counterpart, Admiral Beatty, into the range of the guns of the main German force. HMS Indefatigable was struck by shells from the SMS Von der Tann and exploded, taking all but three of her crew of over a thousand down with her. HMS Queen Mary was hit by shells from SMS Seydlitz and SMS Derfflingler and also blew up, killing all but nine of her crew of around twelve hundred. Even Admiral Beatty's flagship, HMS Lion, was nearly lost.
From there raged the Battle of Jutland, losses mounted, and at the end of the day HMS Invincible, another battlecruiser, had also exploded and killed all but six of a crew of over a thousand. All in all, three of the nine Royal Navy battlecruisers present exploded, and others sustained heavy damage.
Jutland Losses’ Influence on Battlecruiser Design
Though Jutland demonstrated particular weaknesses of the battlecruiser concept, the major naval powers continued to develop battlecruisers after the
conclusion of the First World War. HMS Hood, the sole member of the Admiral class, was the last battlecruiser constructed by the Royal Navy, but she was in fact larger than any battleship fielded by Britain until the Second World War – though her armor was still lighter than that of most battleships. British battlecruiser design reached its peak with the G3 Battlecruiser class, which was to have mounted nine sixteen inch guns and have a top speed of over thirty knots. Meant to outperform even the battleships of most competitor nations, the G3 Battlecruiser continued the battlecruiser arms race until the Washington Naval Treaty led to its cancellation.
Japan's penultimate entry in battlecruiser design was to be the battlecruiser Amagi and its sister ships, the Akagi, Atago and Takao. The name Akagi is likely familiar as it was later converted to an aircraft carrier and took part in the attack on Pearl Harbor and the Battle of Midway. The battlecruiser Amagi was meant to be converted as well – the conversion taking place as a result of the naval arms limitation agreements of the Washington Naval Treaty – but a powerful earthquake so damaged Amagi's hull prior to launch that construction was abandoned.
The G3 Battlecruiser and Amagi designs took into account the bane of the battlecruisers at Jutland: plunging fire penetrating the turrets, causing flash fires in ready ammunition that chain reacted and caused catastrophic detonation of the ship's magazines. The G3 class in particular, if it had not also been canceled due to naval treaties, would have incorporated an all or nothing armor scheme which would heavily protect vital areas, but not less important spaces.
The Last Classes of Battlecruiser: Alaska, Scharnhorst, and Kirov
The Second World War and the latter half of the Twentieth Century saw the battlecruiser wane in importance. During the 1930's the Germans built two vessels they called battleships but that are often considered battlecruisers due to their relatively light armament: the Scharnhorst and Gneisenau. The Deutschland class pocket battleships in part fit the battlecruiser profile, but were employed more like the armored cruisers of past years.
Between the Jutland losses and the destruction of the HMS Hood with all but three of her crew at the hands of the Bismarck and Prinz Eugen (again, by plunging fire igniting magazines), and the advent of the aircraft carrier as the dominant capital ship, the battlecruiser slowly disappeared. The battlecruiser Alaska and her sister the Guam were constructed with a mind towards combating German pocket battleships and rumored Japanese equivalents, but in the end were not even considered battlecruisers by the US Navy – although in size, mission, and cost they rivaled the battlecruisers of other navies.
After the scrapping of the battlecruisers Alaska and Guam the only class of vessels worthy of the name battlecruiser are the Kirov class, a series of four heavy guided missile cruisers built by the Soviet Navy during the Cold War and now under reconstruction for redeployment as part of a revived Russian Navy. Though not officially termed battlecruisers, their armament and size is well beyond even the cruisers used by any other nation. If any class of ships can be considered capable of carrying on the legacy of the battlecruiser, the Kirovs with their twenty large cruise missiles and vast magazines of surface to air missiles are the closest thing to battlecruisers sailing in the twenty-first century.
Sources and Image Credits
Janes Fighting Ships of World War II, 1946 Janes Publishing Company, 1994 reprint edition
Barrie Pitt, The Battle of the Atlantic, 1977 Time Life Books
A Wordsworth Colour Guide Modern Warships; 1993 Wordswordh Editions LTD
Churchill, The Second World War, 1959 Time Life
Images via Wiki Commons and courtesy of (respectively) the United States Navy, the United Kingdom Imperial War Museum, the Australian State Library of Victoria, and Mitsuo Shibata for the US Department of Defense