Pocket Battleships

[skb12172]

I've read the wiki as well as a few other sources. I realize Germany used them to get around tonnage limits on their naval vessels. The Israelis, IIRC, also used them to get as much punch as they could in a vessel operating in the relatively shallow waters they patrolled. My question is this: Is the relatively heavier armament the only thing that differentiates a PB from a regular cruiser? What other sacrifices must be made to account for extra armament over a standard cruiser? Is it really a desirable way to go? If so, why aren't/weren't they more common?

Fire Away!

[Greg]

Israel never used anything that big. They were like most every navy that was only concerned with coastal defense. Since their ships had no need for long range, endurance, crew habitability, etc, they operated small warships that were heavily armed for their tonnage. FAC's up to corvettes or so. (If they had a generous patron they might have a hand-me-down frigate or destroyer or two but nothing larger.)

The German ships were not in any way even remotely battleships, pocket or otherwise. You could sort of call them small battlecruisers, maybe. What they were was very specialized cruisers. They were munchkin ships (think Battletech arena mechs) that were not normal balanced warships but attempts to heavily optimize for one particular scenario. They were long-distance surface raiders, designed to quickly overwhelm solitary London Treaty cruisers - which is what the British used to protect their commerce in distant waters. In actual service, the first time they ran into a fight that wasn't exactly what they were optimized for (which meant the first time they ran into a fight)... they failed.

[Greg]

To elaborate, the 'PB's were the size of largish cruisers for the time, and had relatively normal cruiser armor. But they were designed as solitary commerce raiders not fleet units, so their power plants were designed for maximum feasible range, sacrificing speed.

Their main armament was, compared with other cruisers, a substantially smaller number of substantially larger guns. Big punch if they hit - in theory those guns were big enough that one hit could cripple an opposing cruiser. But the bigger guns had a lower rate of fire per tube than normal smaller cruiser guns, and as mentioned they had fewer of them. Also, with only cruiser sized magazines, they didn't have all that much ammo either (limited space, big shells). But yes they could in theory quickly take down a single opposing 'normal' cruiser. (At that time the British tended to use single cruisers for commerce protection.)

Their top speed was lacking, low rate of fire from few main battery tubes so they would have a terrible time actually hitting a small maneuvering enemy (US 8" gun cruisers had a *terrible* time trying to hit Japanese destroyers. These would have done much worse) and the limited ammo meant limited combat staying power.

So to counter them, the British just had their little trade protection cruisers team up instead of working alone. First PB fight was against 3 small British cruisers. Result was 3 damaged British cruisers (one badly damaged), one PB with some damage and very little ammo remaining hiding in a neutral port. From which it never came out.

While they looked impressive on paper at first, they were a bad investment. They were over-specialized, not versatile and relatively easy to counter.

[Jered]

With the Deutschland, Graf Spee, and Admiral Scheer, the Germans actually cheated the treated limits by 1700 tons.

The point of the panzerchiffe was long range convoy raiding. They massed 11,700 tons. They could go over 18,000 miles. I think they could get up to 26 or 27 knots.

The Hipper class cruisers massed 14,000 tons and could range 5000 miles at 15 knots.

New Orleans Class cruisers could range 10,000 miles at 15 knots.

The heavy cruisers can break 30 knots.

The Graf Spee took hits from 8 inch guns at the Battle of the River Plate that penetrated her armor. None of the six inch hits did so.

So, these ships traded speed for range, and to a certain extent, armor for guns.

From my reading of Fleets of World War 2, it seems that Germany had a role in mind for their pocket battleships similar to what the British envisioned for their battlecruisers in the First World War. They were supposed to be able to run what they couldn't outfight.

Greg got it spot on, these ships were optimized as long range commerce raiders, and they really weren't good for anything else.

[Aesop]

The PBs would do up to 28 kts if necessary. Cruise speeds were a far more fuel-economical 20 kts.
OTOH, full-sized battleships like Bismark did 30 kts, and had a 10,000 mi. range at slower speed, and 8 15in guns. She sank the battlecruiser RMS Hood in eight minutes' attack. And even under fire from multiple battleships like Rodney and Prince of Wales as well as cruisers and aircraft attacks, took quite a beating without sinking.

But even full-sized combatants, as single examples rather than parts of a larger fleet, were no match for massed combatants toe-to-toe.
Like giant oceanic tanks, gunfights always work better in a group.

The counter to German surface vessels, deployed in ones and twos, was to tag-team them with multiple vessels, and aircraft if possible, and it generally worked.
Had they amassed actual task forces, or co-ordinated with U-boat wolfpacks, things weren't liable to have gone as well.

Germany was mainly trying to impede and cut off British sea lanes, not dominate the entire ocean. That was a flaw in strategy, probably owing mainly to the physical realities of where they were, and how big a deal the ground war is when you have to fight on 2-3 fronts simultaneously most times at bat.

Countries like Britain and Japan, and continental powers like the US, have an automatic advantage until nuclear missiles become an option, being surrounded by oceans.
So in geopolitics, if you're contemplating a war, getting off the X (or not starting there in the first place) is good advice anytime before 1945.

[Greg]

Oh yeah, long range maritime patrol aircraft with radar really put paid to the idea of the surface raider. The window for that role was almost closed when Germany built the ships....

[Aesop]

Yeah.
That whole "seeing into the future" thing is a bitch.

Germany did a great job at winning WWI - in 1940.
When tech developments made it a different war, they got left behind again, and got the 2d place ribbon.

Convoys, radar, and ground-based air cover gets you the North Atlantic and Britain. Keeping Britain means you keep control of the Med. Strategic bombing, and an inability of the enemy to mount amphibious assault lets you arm it to launch your own amphibious assaults. Opening a second front soaks up your resources. A + B + C+ D means you don't have the means to stop people coming in and kicking you in the face. Game over.

[Greg]

Yeah.
That whole "seeing into the future" thing is a bitch.

Wasn't *that* much of a stretch. The pocket battleships carried float planes after all, that they intended to use for scouting to find targets.

The way aircraft were improving, it shouldn't have been all that hard to imagine the other side using planes to look for pocket battleships......

[skb12172]

Yeah.
That whole "seeing into the future" thing is a bitch.

Germany did a great job at winning WWI - in 1940.
When tech developments made it a different war, they got left behind again, and got the 2d place ribbon.

Convoys, radar, and ground-based air cover gets you the North Atlantic and Britain. Keeping Britain means you keep control of the Med. Strategic bombing, and an inability of the enemy to mount amphibious assault lets you arm it to launch your own amphibious assaults. Opening a second front soaks up your resources. A + B + C+ D means you don't have the means to stop people coming in and kicking you in the face. Game over.

Being basically one country (Italy doesn't count) and fighting the world doesn't help, either.

[Aesop]

Yeah.
That whole "seeing into the future" thing is a bitch.

Wasn't *that* much of a stretch. The pocket battleships carried float planes after all, that they intended to use for scouting to find targets.

The way aircraft were improving, it shouldn't have been all that hard to imagine the other side using planes to look for pocket battleships......

You have to be looking.

I'm sure some scientists and theorists might have been, but when the boss is a screamer with a 30-year chip on his shoulder...