Armor penetration is a phenomenally complex issue, and one that isn’t wholly understood even today. But a basic explanation is necessary to understand why warship armor was designed the way it was during the dreadnought era.¹ The basic factors that drive armor penetration can be roughly broken down into the armor, the shell, and how they meet. We’ll start with the last of these.

“How the armor and shell meet” boils down to impact velocity and obliquity, or angle of impact. A higher striking velocity is always going to result in higher penetration, all else equal. Obliquity is measured between the axis of the shell and the line normal (perpendicular) to the plate, so 0 obliquity is a direct hit and 80 degrees is a very glancing blow indeed. Oblique impacts have less penetration than direct ones, sometimes significantly so. This is not simply due to the geometry of the impact sending the shell through more metal, despite what most works that discuss armor penetration would have you believe. The front of the shell hits first, and the contact tends to make it rotate, either glancing off or hitting the armor side-first. This is obviously tremendously less efficient than a direct hit, and the usual counter was to design the projectile to dig in to the armor slightly, which would actually reverse this process. A shell hitting and piercing at high obliquity would come out with a lower obliquity than it went in at.²

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Besides the major naval powers, quite a few other countries bought or tried to buy dreadnoughts. Last time I discussed those built as part of the South American Dreadnought race. This time, we'll look at the Ottoman, Spanish, Austro-Hungarian, Greek, and Dutch battleships.

HMS Erin with a kite balloon for spotting

The Ottomans attempted to buy two battleships in the years before World War I. One of them, Sultân Osmân-ı Evvel, began life as the Brazilian Rio de Janeiro, and was discussed last time, while the other, Reşadiye, was ordered by the Ottomans directly, and armed with 10 13.5” guns. The design was similar to the British Iron Duke, although somewhat lighter.³ Like Sultân Osmân-ı Evvel, Reşadiye was seized by the British shortly after she was completed, for fear they would turn her over to the Germans. The ship, commissioned as HMS Erin, served at Jutland, where she fired a grand total of 6 rounds from her 6” secondary battery. Contrary to the experience of Agincourt, she was very cramped.⁴ After the war, Erin was scrapped under the Washington Naval Treaty.

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Armoring a warship doesn’t seem like it should be hard. Figure out how much armor you need to stop what you expect to be shooting at you, and then slap that much on.

Dents on the turret of a Monitor after seeing action

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While Huascar was fighting the Esmeralda, another action was taking place off off Iquique. Another Peruvian ironclad, Independencia, had come with her, and had gone in pursuit of the Chilean Covadonga. This fight was, if anything, even more uneven than Huascar’s. Independencia was five times Covadonga’s size, armored, and three times faster.

Independencia

Covadonga’s captain, Carlos Condell, handled her with skill equal to Prat’s. He stayed close inshore, using the fact that Covadonga drew considerably less water than Independencia to avoid the Peruvian ship. The fact that his gunnery was as good as Independenica’s was bad helped, too. Independencia tried to ram twice, both times taking careful soundings on the way in and aborting when the water grew too shallow. A third attempt occurred near Punta Gruesa, where Covadonga barely avoided grounding. Independenica’s helmsman was killed by a sharpshooter just as she touched the reef, and she ran hard aground. Covadonga rounded and poured fire into Independenica’s stern, setting her on fire. Read more...

Most of the attention given to the dreadnoughts focuses on those of the major powers, Britain, the US, Germany, and Japan, with lesser attention on those of France, Italy, and Russia. But this is not the full story of the big-gun warship. Several smaller nations also bought them before World War I. The most prominent of these ships are those involved in the South American Dreadnought Race.

Minas Geraes in 1910, shortly after delivery

In 1907, flush with cash from a boom in rubber and coffee, and attempting to assert itself as a world power, Brazil ordered a pair of ships from British yards. These ships, the Minas Geraes class, were briefly the most powerful battleships in the world. Each ship had 12 12" guns, and a 10-gun broadside thanks to the unusual combination of wing and superfiring turrets. In response, Argentina and Chile both rushed to order dreadnoughts of their own.

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The story of the ironclad in battle takes us next to the Pacific,⁵ and the monitor Huascar. Built by Laird Brothers of Birkenhead for Peru, she was commissioned in 1866, slightly too late for the war she'd been ordered to fight. 1,870 tons, 220 ft long, and mounting 2 10" guns in a single turret, she was a reasonably powerful vessel for the day, although she was essentially a coastal defense ship. The belt ranged from 2.5" to 4.5", and her maximum speed was 12 kts.

Huascar as completed

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Ran across a 2-part article, and thought I'd share it here. By a former Navy engineer, with lots of interesting bits on running a steam plant. Particularly valuable for his insights into reactivating old ships. I would quibble that there are still people who know how to run Iowa's plan and can make it down the ladder (I've done tours with a couple of them), but that's just nitpicking.

Part 1

Part 2

Today marks the 76th anniversary of one of the most important days in the demise of the battleship. While the Pearl Harbor attack gets much more attention, the sinking of Force Z, the battleship Prince of Wales and the battlecruiser Repulse, at the hands of the Japanese was in many ways more influential. Both Pearl Harbor, and Taranto before it, were made on ships that were at anchor and unaware of the attackers. Force Z was at sea and alerted to the possibility of attack, a condition that many believed would keep it safe.

Prince of Wales in Singapore Harbor

Repulse and Prince of Wales were dispatched to Singapore by Churchill in October of 1941 in an attempt to deter the Japanese from starting a war.⁶ The two ships entered Singapore with four destroyers⁷ on December 2nd. They were greeted with a blaze of publicity unusual during the war. Read more...

As I’ve been talking a lot about ironclads lately, I’m going to discuss one of the weirder episodes of the Victorian Royal Navy. In that era, the most important force in the RN was the Mediterranean Fleet. It was tasked with defending the vital link between Britain and the Empire East of Suez from the French and Russians, Britain’s most probable adversaries in the event of war. The newest and best ships were sent there, as well as the ones with low freeboard, as the Mediterranean is considerably calmer than the Atlantic.

Victoria firing her guns

HMS Victoria was commissioned in 1890, one of the last classic turret ships built. She carried two 16.25” guns in a twin turret, the largest guns ever to arm a British battleship.⁸ The guns were not successful. Slow-firing and inaccurate, they could only fire about 75 rounds before needing to be replaced.⁹ Victoria was sent to the Mediterranean shortly after commissioning, and in 1893, she was still one of the most highly thought-of ships in the RN. Vice-Admiral Sir George Tryon, commanding the Mediterranean Fleet, chose her as his flagship. Read more...

Mr. Vice President, Mr. Speaker, members of the Senate and the House of Representatives: Yesterday, December 7th, 1941 — a date which will live in infamy — the United States of America was suddenly and deliberately attacked by naval and air forces of the Empire of Japan.

The United States was at peace with that nation, and, at the solicitation of Japan, was still in conversation with its Government and its Emperor looking toward the maintenance of peace in the Pacific. Indeed, one hour after Japanese air squadrons had commenced bombing in the American island of Oahu, the Japanese Ambassador to the United States and his colleague delivered to our Secretary of State a formal reply to a recent American message. And while this reply stated that it seemed useless to continue the existing diplomatic negotiations, it contained no threat or hint of war or of armed attack.

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