Battlecruisers, at least in theory, seem like a great idea. However, having a lot of firepower but very little armor is a big problem that cannot be easily solved: “There seems to be something wrong with our bloody ships today,” Admiral Beatty said as he watched his battlecruisers explode one by one in the Battle of Jutland.
The words were a classic British understatement, but 3,000 dead sailors was proof enough that something was indeed wrong with ships that were neither battleships nor cruisers.
It was not meant to work that way when the British Grand Fleet met Imperial Germany’s High Seas Fleet off the Jutland Peninsula in Denmark on May 31, 1916. Battlecruisers were meant to be a solution to a problem, not a problem in itself.
The concept seemed quite logical. Battleships were heavily armed and heavily armored, but too slow to hunt down smaller, faster warships such as cruisers. On the other hand, cruisers lacked the firepower and protection of battle wagons. So why not combine the two in a ship the size of a battleship armed with the big, long-range guns of a battle wagon, but with the speed of a cruiser?
They could use their speed and firepower to drive off enemy warships and trade raids. If they encountered enemy battleships, their superior speed would allow them to escape. Battlecruisers were meant to be a sort of seafaring Muhammad Ali: they would flutter like a butterfly and sting like a bee.
Compare the Royal Navy’s Queen Elizabeth-class battleships and Renown-class battlecruisers, which fought in both World Wars; they were both armed with fifteen-inch guns, but the battleships had a top speed of twenty-four knots, while the battlecruisers could run at thirty-one knots.
However, there is no free lunch in warship design. You can have armor, firepower, or speed, but not all three, and armor was the trait that was sacrificed. The battleship HMS Spite of war was protected by a belt of armor between the deck and the waterline that was up to thirteen inches thick. Meanwhile, the battlecruiser HMS fame had a maximum of only six inches of armor.
The consequences became evident in Jutland when three of the seven British battlecruisers blew up, victims of direct hits from German battlecruisers. Another notorious example is the HMS hood, which also exploded after a fifteen-inch shell from the German battleship Bismarck apparently plunged through the thin deck armor and detonated the magazine. Not surprisingly, most battlecruisers never reached old age. Several were converted into aircraft carriers between World War I and World War II, including the USS Lexington and Saratoga. Many more were sunk, including the Japanese Kirishima and Hiei at Guadalcanal (the Kirishima was sent by the American battleship Washington), while the HMS Repel was sunk off Malaysia in December 1941.
What went wrong? And was the problem with the ships or with the way they were used? In some cases, the problem seems more tactical than technical. British doctrine during World War I emphasized smothering the enemy with rapid broadsides, even at the expense of safe ammunition handling procedures. This made British warships more vulnerable to munitions explosions. Indeed, it should be noted that the squadron of German battlecruisers came under fire from most of the British battleship contingent, but most of them managed – albeit hard-fought – to reach port. Clearly, superior German ship design and tough Krupp steel made the difference.
In the battle of Denmark Strait, the Royal Navy was so determined to bring the Bismarck into battle before it could reach the Atlantic convoy routes, that an old First World War battlecruiser, HMS hood, loaded directly onto a state-of-the-art 1940s battleship. Repel, meanwhile, was sunk by Japanese torpedo bombers alongside her companion, the battleship Prince of Wales.
The battlecruiser concept seemed flawed from the start. Like many hybrids, they suffered from an identity crisis. Should they be used as battleships in large fleet actions, or more like cruisers, to detect and harass the enemy, then get out of the way while the big boys fight them? In Jutland and the Denmark Strait they were deployed as capital ships, where they proved too fragile (but for another view see here). This is a question that continues to plague the design and employment of weapons. Is a $150 million F-35 supposed to be used as an air combat capable fighter? An attack aircraft that will stand offshore and launch air-to-surface missiles? Or will it come in the teeth of enemy air defenses as a close support aircraft?
The irony is that even though the battlecruisers are gone, they are still with us today. Battlecruisers were eggshells armed with hammerheads, which exactly describes modern warships. Today’s combat ships carry weapons of astounding lethality, especially anti-ship missiles. They also defend themselves with cannons and missiles to take down incoming weapons with a technological finesse that would have seemed like an HG Wells novel to a sailor in 1914.
But what if a missile hits them? Just a hit, as we saw with the HMS Sheffield and USS Rigid, can sink or cripple a ship. Even if it didn’t sink, the sensors, computers, and electronics would likely be so fried or jostled that the ship would be effectively immobilized. Certainly there have been improvements in materials and damage control. But at the end of the day, a modern warship has a lot more firepower than it can handle.
That doesn’t mean we have to build an Aegis cruiser with the armor of the USS New Jersey battleship. The way the arms race works, it’s easier for the enemy to design a more powerful killer ship than to keep hoarding armor that will only make a ship heavier and more maintenance-intensive.
But if a major naval conflict breaks out, in the South China Sea or the Persian Gulf, the ocean could be littered with many broken eggshells.