June 27, 2018

Rangefinding

It's been too long since Naval Gazing covered fire control. As such, I'm going to start looking at the details of various portions of the fire-control process, starting with the rangefinders.

In the early days of naval fire control, many different solutions were proposed for the problem of finding range. All optical rangefinders operate on essentially the same principle, that you can construct a triangle, and knowing one side (the baseline) and some angles, use basic trigonometry to work out the other sides, one of which is the desired range.

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June 24, 2018

Auxiliaries Part 2

Last time, we talked about how, in the years leading up to World War I, the US Navy developed an array of auxiliary ships designed to support the fleet in the absence of permanent bases. Most prominent among these were the oilers, some of which were used to refuel ships at sea. During the 1920s, as the plans for the war against Japan developed, it became increasingly obvious that the USN would need the ability to reliably refuel ships at sea to carry it off. While the latest destroyers were longer-ranged than the ships Maumee had refueled in the mid-Atlantic, their range was still insufficient for the broad Pacific. As a result, the alongside method of refueling was developed and perfected, to the point that it had become almost routine for the smaller craft. In addition to the oilers, battleships and carriers were also equipped to refuel their escorts.


Sabine refueling Enterprise during the Doolittle Raid

But the destroyers were not the only ships with worryingly short legs. The pre-turboelectric battleships had inefficient engines, and a method of refueling them at sea was desired. However, the alongside method was considered far too dangerous for use with any ship larger than a destroyer. Instead, trials were made of refueling over the stern. This removed the threat of small helm errors causing disaster, but turned out to have intractable problems of its own. The fueled ship had to be far astern, which limited flow rate and required inordinate pumping power.1 Special equipment was required to keep the lines supporting the hose under tension. If the hose sagged into the sea, the oil would cool and thicken, interrupting the refueling.2 Ultimately, the problem was solved by refitting the battleships in question with more efficient geared powerplants, and the matter of refueling big ships rested for the next decade. Read more...

June 22, 2018

Did Iowa Move Sideways During a Broadside?

It's a common belief that battleships moved sideways when they fire. I've talked with people who were aboard at the time who swear to it. But I'm an engineer, and thus believe the question can and should be answered by doing math.


Seriously, what picture did you expect me to use for this?

Let's assume we're trying to get Iowa moving sideways as fast as possible by firing the guns. We'll take only a minimal load of fuel and ammo, and turn the ship into a hovercraft without adding any weight, so there's no water resistance to slow her down.3 Dulin & Garzke list Iowa's 1943 light displacement as 44,579 metric tons.4 This is definitely low, but I'm willing to use it as an analytic assumption. Now, about the momentum of the broadside. Each AP shell weighs 2700 lb or 1224.7 kg. The muzzle velocity is 2500 ft/s or 762 m/s. A full 9-shell broadside thus has a total momentum of 8.4*10^6 kg*m/s, for a hovercraft side velocity of .1884 m/s, or .3662 kts. Or about 7.5 inches per second for those who don't instinctively think in knots.

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June 20, 2018

Second-Generation Battlecruisers

The first battlecruisers were the product of Jackie Fisher's efforts to find a more cost-effective way to protect British trade. They were the size of contemporary battleships, trading armor for guns. The Germans answered with ships that were better-balanced, with lighter armament but battleship-scale armor.

Around 1909, the battlecruiser grew rapidly, much as contemporary battleships did. In Britain, this was spearheaded by HMS Lion and her sister ship, Princess Royal, both part of the "We want eight" 1909-1910 program. Lion was the first British ship armed with the 13.5" gun, a change from the slightly improved Indefatigable originally planned that was made possible because she was being built in the Royal Dockyards instead of a commercial yard. Making late changes to a design in a commercial yard would have meant serious penalties under the contract, but the Dockyards were under the navy's direct control.5


HMS Lion

Lion was a dramatic move away from the previous lightly-armored battlecruisers and into a ship that was more of a fast battleship, although not to the extent of the German battlecruisers. The 9" belt was 50% thicker than those of the previous classes, and a 6" upper belt was fitted, something completely absent from the previous classes. One of the major drivers for this was the increase in battle ranges, which meant that armor was now potentially useful against heavy shells. The four 13.5" twin turrets were finally all on the centerline, including a superfiring turret forward.6 Speed also increased from 25 to 28 kts, to match the German Moltke. Read more...

June 18, 2018

Open Thread 2

Because of the success of the last open thread, I'm inclined to try another one. Talk about anything you want except culture war.

Also, I'm going to be in Boston this summer, July 19th-24th. I expect to hit a lot of the museum ships up there, and want to do a meetup at one if there's interest.

June 17, 2018

Jackie Fisher

John Arbuthnot "Jackie" Fisher was perhaps the most important naval officer of the 20th century, despite never commanding a fleet in battle. His career began on the deck of a wooden sailing ship and ended with a fleet of dreadnoughts, destroyers, submarines and even the first steps towards aircraft carriers. Even more astonishingly, he was the man most responsible for many of these developments, some of which continue to shape naval warfare today.7


Jackie Fisher

A brilliant, energetic, innovative, and ambitious man, he was also stubborn and prone to obsession. At his best, he saw the shape of things to come better than any of his contemporaries, and even better than many today. At his worst, he assumed that the future had already arrived, and tried to build ships that were simply not possible yet. He was a constant proponent of reform, ranging from improving conditions for enlisted seamen to the development of Dreadnought, but was uncompromising in his dealings with those he saw as his enemies. Read more...

June 15, 2018

So You Want to Build a Modern Navy - Aviation Part 1

Bean: I think it's probably time to look at our options for fixed-wing aviation at sea. As I see it, we have a couple ways to do this, and I'm not sure which one we should go for.


HMS Queen Elizabeth

First, we could buy full CATOBAR carriers like the US and France use. These would be smaller than the US carriers, ideally about the size of the British Queen Elizabeths, although we might be able to go a bit smaller. The advantage is that this gives us the best payload and the widest range of aircraft options. One of the highlights would be being able to fly E-2 Hawkeyes, giving us one of the best AWACS planes in the world. The problem is that ships that big are also expensive, and we'd have to develop a whole new set of skills. We do have aircraft options here, though. We could buy either Dassault Rafales or Boeing Super Hornets, and we'd probably get a pretty good deal on either one. Even better, we could fly the same plane from our land bases, giving us commonality between our sea and land based squadrons.

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June 13, 2018

The Battle of Pungdo

After Lissa, fleets of ironclads didn't clash for almost three decades, and when they finally did, it was in the Far East. The Japanese, increasingly assertive in the wake of the Meiji Restoration, desired to end centuries of Chinese sovereignty over Korea. This tension spilled over into Korean politics, which became increasingly bloody, and in 1885, Japan and China signed the Convention of Tientsin, limiting troop deployments to Korea.

In 1894, a major peasant revolt broke out, and China sent 3,000 men to suppress it. Japan responded by sending 8,000 troops, claiming that the Chinese had not informed them as required under the Convention. These troops replaced the Korean government with a pro-Japanese one. At this point, war was inevitable.

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June 10, 2018

The Falklands War Part 3

After Argentina invaded the Falkland Islands in 1982, the British frantically prepared their fleet to sail to the South Atlantic and recapture them. The 8,000-mile logistics chain included only one base, Ascension, a tiny island in the central Atlantic.8

Ascension was critical to Britain's counterinvasion of the Falklands, providing the base where the Task Force assembled and sorted itself out after its hasty departure from the UK. Ascension was primarily used as a base by the Americans, who had a NASA tracking station and a signals intelligence center on the island. Wideawake Airfield, with a 10,000 ft runway, would be vital. Although the runway was enough to support virtually any airplane, it had no taxiway and only a small hardstand, and the operations contract with Pan Am provided for only 285 aircraft movements per year. At the height of the operation, Wideawake would see more than 300 aircraft movements in a day, making it the busiest airport in the world.


Ascension viewed from the ISS, with Wideawake at the bottom

Ascension's other facilities were equally bare-bones. There were no hotels, and visitors were not allowed without permission from the British Administrator. Children reaching 18 who were not employed were required to leave. There was a golf course, but it was among the worst in the world due to the lack of greenery.9 Ascension did not have the facilities to support a large influx of visitors: the island's supply of fresh water, produced by desalination, was very limited, and there was virtually no shelter for the new arrivals. Read more...

June 08, 2018

Museum Review - USS Alabama and Battleship Memorial Park

I visited Alabama again in 2025, and came away with a much better impression of the ship. If you are looking for information on the current state of Alabama, please read that review instead. I leave this one up only for historical interest.


I visited Alabama in December of 2015, on a Friday. It was only weeks after I started at Iowa, and I was excited to get a point of comparison and to see stuff I hadn't gotten to see before. Ultimately, though, I wasn't impressed.


Me at Alabama
Type: Museum Battleship with Submarine and Air Museum
Location: Mobile, Alabama
Rating: 3.8/5, Not bad, but definitely the weakest of the big ships I've been to10
Price: $15 for normal adults

Website

Alabama, in Mobile, is a decent way to spend an afternoon. She's a member of the South Dakota class, and still pretty much in WWII configuration, which was a big change from Iowa. A lot of the ship is open, including the turrets, a combined engine/boiler room, one of the magazines, and most of the living space.

My biggest complaint was that I didn't see anyone there who wasn't directly involved with making money. Just to be clear, I totally understand that something of this nature is a fiscal black hole in the shape of a ship. I'm not criticizing them for trying to soak guests for all they can. We at Iowa do the same thing. My problem was that there was nobody there whose job was to make my visit better. That's what I did on Iowa, and I was disappointed that they didn't have anyone doing that sort of thing. Also that I didn't have anyone to geek with.

Beyond that, the museum aspects were really variable. For a ship which has been open for 50+ years, some parts were just not that well done. The turrets, while open, had such poor lighting that I can only conclude that personal injury lawsuits do not exist in Alabama, and basically no signage. A lot of spaces looked like they'd been stripped out and then had the major elements reinserted. The bulkheads were way too clean, and even the spaces that had been dressed up as if they were live were a bit spartan. Some spaces were good, such as the engine room and particularly the magazine they had opened up. Another thing I noticed is that the ship is deep in the mud, and doesn't move like a proper ship. It feels weird. I know you may not think I could tell, but I promise you that you do feel it if you've spent time shipboard recently.

The rest of the facility was better. The USS Drum, a WWII fleet submarine, is next to the battleship. While it's on land, it's much closer to its original condition, and I enjoyed it more than Alabama, at least per-minute. There's a medium-sized air museum, and some outdoor military hardware displays, too. They have an A-12 spyplane (predecessor to the SR-71) and a YF-17 prototype, along with a pretty good collection of planes from Vietnam and later eras. Their WWII stuff is pretty standard, the sort of stuff that can be seen anywhere.

It's entirely possible that I'd have a very different review if I'd gone on a day where they had a couple of guides on hand. It certainly wasn't a bad day, although I'd much rather spend the day on Iowa, Midway or Massachusetts, which is the one to visit if you really want to see a SoDak.


1 The various transfer equipment required so much power that the speed of the oiler was reduced to about 6 kts.

2 Later on, astern refueling was used fairly extensively during WWII. It was the primary method used for the Japanese heavy ships, although they had the ship being refueled in front. The British fitted their tankers for both alongside and astern refueling, and both methods were used to pass fuel from merchant tankers to destroyers escorting the Atlantic convoys.

3 This is not a serious proposal, and I would be most annoyed at anyone who actually did it.

4 Ships are traditionally measured in long tons of 2,240 lb. I use this everywhere on the blog, but metric tons are easier to do math on.

5 This also applied to Orion, and to many later ships on both sides of the Atlantic.

6 There was a late proposal to stretch the ship 3 frames (12') and add a second turret superfiring aft. The marginal cost, except to the armament budget, was minimal, but for unknown reasons, the suggestion was not adopted.

7 Even teenage girls owe him a debt, actually. He's also the inventor of the abbreviation OMG.

8 I've written a glossary to make it easier to keep track of terms in this series, and the full list of posts is here.

9 It was a facility run by the US Air Force. Of course there was a golf course.

10 One reader has given a more positive review of Alabama, and I'll freely admit that circumstances for my visit were less than ideal. My second visit resulted in a 4.6/5.