The late 19th century saw the development of smokeless powder, which replaced the traditional black powder with something that was more powerful, burned more consistently, and was hopefully safer. These powders were split into two categories: single-base powders that were based entirely on nitrocellulose and used by the US and France, and double-base powders that contained nitroglycerine as well, and were used by the British and Germans. Before the war, a number of ships were destroyed by internal explosions, but it was believed that these had mostly been solved.

HMS Bulwark explodes

Unfortunately, this was not the case. The first warning came to the British in November 1914, just after the outbreak of war, when the pre-dreadnought Bulwark exploded after some cordite charges were left against the boiler-room bulkhead, killing all but a dozen men onboard. Neither this nor various prewar explosions nor the loss of the armored cruiser Natal a year later to a similar explosion were enough to shake British confidence in their cordite, as they had run a number of tests which seemed to confirm its safety. None involved a reasonable quantity of cordite in a confined space, an oversight that would prove disastrous on one day in 1916. Read more...

It's time once again for our regular Open Thread. Talk about anything you want, so long as it's not culture war.

I'm going to highlight a non-naval military history resource. Nicholas Moran, also known as the Chieftain, is a tank historian, but a really good one. He's also a tanker in real life, and spends a bunch of time on the bits like ergonomics and maintainability that aren't nearly as easy to find in a typical reference book. The best series is probably "inside the Chieftain's Hatch", where he crawls over a historic tank and talks through all of the various features.

He works for wargaming.net, the people behind World of Tanks and World of Warships. I have extremely mixed feelings about them. They're an Iowa sponsor, and I'm grateful for that, as well as for the amount of money they've pumped into military history in general, but I also am not a huge fan of their products. And the less said about their video on the Iowa, the better.

On another note, I'm planning on dusting off some of the "So You Want to Build a Modern Navy" stuff for the virtual meetup tomorrow. Just in case anyone was wanting more of that.

2018 overhauls are Missouri Part 2, Nautical Measurements,* Falklands Part 5, Underwater Protection Part 1, My review of the International WWII Museum and the Standard Type battleships. 2019 overhauls are turret designations, Naval Weddings and wedding decorations, Spanish-American War parts seven and eight and Falklands Part 17.

The development of smokeless powder in the late 19th century marked a radical change in gun propellants. Previously, all powder had been a mechanical mixture of oxidizers and fuels, and had turned less than 50% of its weight into gas, with the rest (mostly potassium compounds) making up the bulk of the smoke. Smokeless powders were single substances which could turn completely into gas, reducing smoke and increasing the energy released.

Paul Vieille

The first chemical explosive to be discovered was nitrocellulose, also known as guncotton, in 1846. Nitrocellulose is produced by the application of concentrated nitric acid on cellulose, the usual source of which is either cotton or wood shavings. Early nitrocellulose was unstable and dangerous to make, and a practical method didn't arrive until the 1860s. Even then, it burned entirely too quickly to be suitable for use in guns, because it was still cotton-like, allowing virtually the entire mass to burn at once. Instead, it was used primarily in torpedoes and mines and for blasting purposes. It wasn't until 1884 when the first proper smokeless powder was produced, by French chemist Paul Vieille. His Poudre B consisted of a mix of different types of nitrocellulose, some with more nitro groups than others, gellatinized using ether and an alcohol. It was then rolled into flat sheets, dried, and cut into strips or squares. This meant that only a relatively small proportion could burn at any one time, spreading out the gas production and making it a viable propellant.¹ Read more...

Gunpowder first revolutionized warfare in the 13th century, with the invention of practical cannons. Over the centuries, improvements in powder went hand-in-hand with developments in gun design. But it wasn't until 1839, when French scientist Guillaume Piobert figured out how powder burned, that research could be placed on a truly scientific footing.

Different sizes of black powder grains

The ideal powder would instantly produce enough gas to reach the maximum pressure the gun could safely stand, and then moderate its burning rate to keep the pressure at the same level until the projectile reaches the muzzle. This is obviously impossible in practice, because as Piobert figured out the rate of gas production is proportional to the surface area that is currently ignited (in other words, powder burns only on the outside, and thus outside-in), and also rises with increasing pressure, although the relationship is more complicated and depends on the powder. Read more...

Gentlemen,

It has been a busy year for us. We've commissioned two battleships, a carrier and 10 destroyers, and, thanks to increased tensions with Germany, laid down a carrier, two light carriers and one heavy and three light cruisers. We also refitted four of our old BCs and started a major modernization for Saint Louis. And we have a significant budget surplus even after all of that.

The biggest concern is what to do about Germany. We defeated them a few years ago, but tensions are creeping up again. Fortunately, our alliance with the British is holding strong, and we should be able to face them if necessary. As for what to do with the surplus, the staff has worked out a design for a 70-plane 28,000-ton carrier, which should be able to help give us a serious striking force against their fleet. Another issue to address is the potential escort shortage. Our 600 and 700 ton destroyers are overage, and it might be a good idea to build new corvettes to replace them. On the good news front, we also recently developed the technology for dive bombers, and have a design in work. Read more...

All guns work on the same basic principle. Something is burned inside a tube, and the burning produces gas which pushes the projectile out. Traditionally, this something was gunpowder, also known as black powder, and by extension pretty much all solid propellants² for guns are known as powder.

Black powder is a mix of saltpeter (potassium nitrate), sulfur and charcoal, and was discovered in China during the early 9th century. Early formulations were only useful for fireworks and incendiaries, but by the 13th century, the knowledge had spread across Eurasia and the recipe had been improved to the point that cannons as we know them today were practical. The saltpeter is the largest ingredient by weight, and provides oxygen, allowing combustion of the other two components to occur much more rapidly than would otherwise be possible. Charcoal is the main fuel, while the sulfur lowers the ignition temperature of the mixture, improving reliability. When they burn together, about 43% of the mass becomes gas, while the rest remains solid. Most of this leaves the gun as thick smoke, but some remains behind to foul the weapon. Read more...

The Hanford Site, in southeast Washington State, was one of the fruits of the Manhattan Project. It was chosen because of ready access to hydropower and cooling water from the Columbia River and a large area of land well away from the coasts. These were the necessary conditions for the site that would house the plutonium breeder reactors which produced the vital ingredient in the world's first atomic bomb.

Me with some friends in front of the main face of B Reactor

Website

Hanford's active role in plutonium production continued until 1987, but as the Cold War wound down, the government realized that it was now the largest single contaminated site in the country. Work on environmental remediation began, and continues to this day. As you'd expect, the site is not accessible to the general public, but the various organizations involved (Hanford is the subject of some truly bizarre jurisdictional overlap) run occasional guided tours on certain days over the summer, which require advance ticket reservations. At least at the time I went (summer 2015), there were three major tours: one covering the site as a whole with an emphasis on cleanup, one specifically focusing on the Manhattan Project, and one looking at the history of the site before Leslie Groves and his minions showed up. I was able to go on the first two, which is what I expect most here to be interested in. Read more...

It's time once again for our regular open thread. Talk about anything you want, so long as it isn't Culture War.

I'm going to declare this OT the occasional "suggest topics for future Naval Gazing" thread. I don't promise to actually implement any of the suggestions, but it's always helpful to get a look at what people are interested in.

Also, note that our next Naval Gazing virtual meetup will be on Saturday the 21st instead of the 14th or 15th. Sister Bean is getting married, so I'll be on the road.

2018 overhauls are The 15" Battleships, Museum Ships - United States, my pictures from Wayne E Meyer, Information, Communication and Naval Warfare Part 1, So You Want to Build a Modern Navy - Aviation Part 3 and my look at the Operational Intelligence Center in WWII. For 2019, overhauls are Wolverine and Sable, Italian Battleships in WWII, So You Want to Build a Battleship - Trials and Commissioning, How to Build a Battleship - 1942, The Maximum Battleship and the Spanish-American War Part 6.

The most powerful weapons in the world are useless if they don't hit, and during the battleship era, an incredible amount of ingenuity went into solving the problems of fire control. So far, I've covered in some detail problems like finding the range in the first place and keeping track of it during an action. But as good as those systems were, there was no real possibility until the development of radar that they would pinpoint the target closely enough to get immediate hits. For that, the gunnery team of a ship would use the best data it had, the splashes of its shells that missed the target.

Shell splashes rise near a practice target

In the early days of modern naval gunnery, it was common for each gun to fire independently. Ranges were short, and the gunner could spot his shell's impact by eye. But as ranges climbed, it became easy for a gunner to get confused about which shell was his, and apply the wrong corrections. The solution to this was salvo firing, where a group of guns were fired at once, using the same set of targeting data passed from the central transmitting station. The shells would fall in a cluster, and while hits tended to be invisible, misses raised large splashes. A spotter, usually stationed high on a ship's mast in or near the director, would track where these were and pass that information to the fire-control team, who in turn updated their solution for the target's range and motion. Read more...

In the aftermath of the Crimean War, relations between Britain and France soured. The British were particularly concerned that steam power, still a novelty, would render their traditional strategy of close blockade obsolete, and make an invasion easy to pull off. As a result, and despite experience in the Crimea suggesting that fortifications were generally overrated, a commission was set up in 1859 to determine if Britain needed new fortifications, and if so, how many. The commission recommended a large program of fortification at the ports on the south and east coasts of England, and the program was pushed through by the Prime Minister, Lord Palmerston.

Horse Sand Fort, a sea fort guarding Portsmouth

Unfortunately, this all took place right before the American Civil War gave final proof that the masonry forts which had dominated coastal defenses for the first half of the 19th century were obsolete. The so-called Palmerston Forts mostly belonged to this type, although some forts made extensive use of iron plates to supplement their masonry walls. They also introduced a gun mounting that would become common over the next half-century, the disappearing gun. This was a variant on the barbette mount which improved protection by lowering the gun entirely below the parapet for loading, then bringing it back up to fire.³ This mount had a number of advantages over the casemates used by previous forts. It provided more protection to the crew, the positions themselves were cheaper and lighter to construct, because they were simple pits instead of massive masonry structures, and they were much harder for attackers to spot. It was also easier and faster to load the gun after it had been retracted than to do so in a more traditional mount. Read more...