A Blog for Dallas Area Catholics

Flightline Friday Thursday edition – America’s Battlecruisers May 15, 2014

Actually this is a Fullbore Friday.

The battlecruiser was a concept invented by the incredibly prolific mind of First Sea Lord Admiral Sir Jackie Fisher, who dominated the pre-WWI Royal Navy like no man before or sense.  Fisher invented a number of weapon systems that would play a huge role in the coming decades – the dreadnought or all big gun battleship, the battlecruiser, the incorporation of destroyers into fleet actions, and the submarine. He did not invent the latter, but turned it from a toy or curiosity into a serious weapon of war.  Fisher did much more than just invent new tactics or architecture, he also revolutionized Royal Navy training, putting the world’s dominant navy into a position to much more effectively fight, and win, the First World War.

Of all his concepts and initiatives, by far the most controversial was the battlecruiser.  The battlecruiser was something of a hybrid between a battleship and a cruiser, a ship designed to outfight anything it couldn’t outrun, and outrun anything it couldn’t outfight.  A battlecruiser carried the same main armament as a battleship – 12″, 13.5″, or 15″ guns – but had the speed of a light cruiser, going from 25 kts in the earliest ships to over 30 kts later on.  But they had an Achilles heel, to obtain the high speed and

Battlecruiser HMS Tiger

heavy armament, something had to be sacrificed, and that something was protection.  Battlecruisers, especially British battlecruisers, received scant armored protection.  This was to have tragic results when battlecruisers were inappropriately committed to major fleet actions.

The idea behind battlecruisers was that they would hunt down and destroy enemy commerce raiders.  Since cruisers had typically been used in that role, it was thought that battlecruisers would be a great defense against commerce raiding surface ships.  And since the British nation depended on overseas commerce for its survival, it made sense to commit serious resources (battlecruisers and battleships were extremely expensive) to defend against commerce raiders.

The battlecruisers were, however, never without critics.  While Fisher trumpeted their speed and hitting power, critics saw them as expensive sitting ducks if they ever came across either an enemy battleship, or if the enemy developed their own battlecruisers.  And this is something the enemy – His Imperial German Majesty’s Navy – did, and because they could see and observe the capabilities of the first, British battlecruisers, the Germans did theirs much better. At the very least, battlecruisers seemed to some in the Royal Navy as an expensive gamble.

But early in the war it seemed the gamble had paid off.  During two early engagements, the Battle of the Heligoland Bight and the Battle of the Falkland Islands, British battlecruisers dominated and won the day.  They were employed exactly as Fisher had envisioned at the Falklands, crushing a larger fleet of German cruisers which were slower and much less heavily armed.

However, all the battlecruiser’s deficiencies were revealed in glaring detail at the largest single naval surface engagement in history, the Battle of Jutland (technically, the Battle of Leyte Gulf was a larger battle in terms of combatants, but Leyte Gulf was more of a series of engagements rather than one single battle).  As I said, the Germans had studied and observed the British battlecruisers and built their own. The German ships were much, much better, especially in terms of armor protection.  They were really prototype fast battleships.  At Jutland, three British battlecruisers exploded and sank spectacularly with nearly all hands after their thin armor plate failed to stop heavy German shells from penetrating to their magazines.

The famous loss of the HMS Hood in World War II is widely believed to have been due to the same cause – dramatically insufficient horizontal, or deck, armor, which protects a ship from steeply plunging shells fired from long range.

In spite of this experience, battlecruisers still had their supporters.  The German battlecruisers, after all, had taken a terrific pounding, hadn’t they?   Some German battlecruisers were so holed by British shell fire they returned to port with their decks awash, but they still survived.  Maybe the concept wasn’t fatally flawed?

Lexington Class

So the thinking went, and so the United States, in a largely unknown massive naval armaments program that got wound up after World War I, began construction on its own battlecruisers.  Almost 900 feet long, displacing 45,000 tons, the Lexington Class were sleek, fast ships, with a projected speed of 33 kts.  Armed with 16″ guns,, they would have been very thinly armored and very similar to the British ships that had such a bad time at Jutland.

Fortunately, cooler heads prevailed, and the nascent naval arms race after WWI between Japan, the US, and Britain was effectively cancelled by the Washington Naval Treaty of 1922.  It suspended all battleship/battlecruiser construction for ten years (with a couple of caveats) and attempted to impose a “treaty limit” on all battleships of 35,000 tons displacement.

By the time the US and other nations began arming for WWII, technology and tactics had advanced to lead to a new type of battleship, the “fast battleship,” which had heavy armored protection but exceeded the formerly

Deutschland Class

“standard” battleship speed of about 23 kts.  Ships like the US Iowa and South Dakota classes, the British King George V class, and the German Bismarck class were all fast battleships, heavily armed, armored, and fast.

However, the idea of an ultimate “cruiser-killer” remained an attractive one, and some navies continued to play around with the battlecruiser or super-cruiser concept.  The Germans actually got the race started in this case, designing the Graf Spee type “pocket battleships,” or battlecruisers, in the late 1920s.  Supposedly just normal cruisers, and supposedly limited to the Washington treaty’s limitation of 10,000 tons displacement, the Deutschland class actually displaced more like 15,000 tons and had near-battleship armament of 11″ guns.  The French responded with their own near-battleships, the Dunkerques, and the race was on.

To deal with the threat of these new battlecruisers, the US Navy decided to develop its own “large cruiser,” or battlecruiser, what became the Alaska Class.  Equipped with a new 12 inch gun with more hitting power than the 14″ guns of its WWI era predecessors, the Alaska Class was designed to take on these new super-cruisers, or

USS Alaska

battlecruisers, and also to outfight the large number of 8″ gunned heavy cruisers the Japanese had in service.   Germany, too, had developed very large and powerful 8″ gunned cruisers, and there was fear the US counterparts would not measure up.  The Alaska was designed to deal with both.

Interestingly, it was not so much the US Navy that pushed for the development of the Alaska Class, but Franklin Roosevelt. He was a former assistant secretary of the Navy from the WWI era, and had a certain interest in naval matters.  He more or less pushed the Alaska’s on a fairly reticent Navy, which didn’t see much need, at this point, for a new battlecruiser.

As such, development was slow, and always a relatively low priority.  Even though the design process had started in the late 30s, the first ship was not completed until mid-1944.  By that time, the threat they had been designed against had more or less evaporated, and no one was sure what to do with them.  The two Alaskas completed wound up escorting carriers and conducting a few independent missions of minimal importance.

The Alaska’s were basically scaled up versions of the Baltimore-class heavy cruisers.  They were not given anything nearly like battleship levels or protection.  Armor was much more on a cruiser scale than battleship scale, although their 12″ turrets were well armored.  Belt and deck armor was heavier than most cruisers but lighter than a battleship’s and covered much less of the hull.  To keep weight down, the Alaska’s were given virtually no underwater protection against torpedoes, making them very vulnerable in that regard.

There has long been a huge debate in naval circles whether the Alaska’s were “large cruisers” or battlecruisers.  The question is really moot, although there are arguments on both sides.  Since a battlecruiser was really just a scaled up cruiser all along, I’ve always called them battlecruisers.  One significant difference between a cruiser/battlecruiser and a battleship, is the difference in length-to-beam ratio.  Battleships tend to be much fatter, even if fast battleships like the Iowas somewhat cut against that trend.  As you see in the photo at lower left, even compared to an Iowa class battleship, the Alaskas had a sleek, narrow planform.

USS Alaska with USS Missouri above

They were, indisputably, extremely handsome ships.  They never even came close serving in their intended role against enemy surface vessels, so there has been much speculation as to how well they would perform.  I can say that some fairly decent naval simulation games like Harpoon generally show the Alaska’s being dominant over contemporary heavy cruisers.

After the war, the Alaska’s were decommissioned and put in reserve just as soon as possible, even before some WWI-era battleships.  Both were out of service after spending much of 1946 ferrying US servicemen home.  Neither ship was ever recommissioned again, in spite of many different plans to do so.  There were all manner of conversion programs envisioned for the Alaska’s, from turning them into guided missile battlecruisers to huge command ships, but the expense was always too great, and so they were sent to the scrappers in 1959.

Basics:

Alaska Class Battlecruiser

Displacement: 29,800 tons (normal), 34,500 tons (full load)
Length: 808 ft
Beam: 92 ft
Draft: 27 ft

Propulsion:  Essex-class carrier fit of 8 boilers, 4 turbines/shafts, 150,000 hp
Speed: 33 kts

Armament: 9 x 12″50 cal Mark 8 guns, 12 x 5″/38 cal dual purpose guns, 56x40mm AA guns, 34x20mm AA guns

Armor:

Main side belt 9″ tapering to 5″ at waterline, deck armor 4-6″