On the protection of Russian dreadnoughts from the detonation of ammunition
It is well known that at the beginning of the First World War, both German and British battleships and cruisers were prone to tragic death when an enemy shell penetrated into the barbettes of the main caliber towers. The reason was that ammunition was supplied to the guns almost directly, which is why a strong explosion inside the turret or barbette led to the spread of fire along the entire supply chain of ammunition up to and including their cellars.
In the battle at Dogger Bank, Hochseeflotte learned an extremely painful, but also extremely useful lesson. A heavy British 343-mm projectile hit the barbette of the aft turret of the battlecruiser Seydlitz. There was an ignition of charges in the working compartment of the tower, and the fire passed into the turret compartments and reached the artillery cellars. As if that weren't enough, the door to the turret compartment of the adjacent turret was open, causing the fire to spread to it as well. The ship was on the verge of death, and only quick and clear actions to flood the cellars saved it from an explosion. But both aft towers still burned out, at least 153 people died in them.
That same hit
However, a detailed description of the damage to the Seidlitz at the Dogger Bank is beyond the scope of this article. The only important thing is that the Germans wisely used the experience bought at such a high price.
Before the battle at Dogger Bank, the German ships, as well as the British, had a similar scheme for supplying ammunition to the main caliber guns. Both shells and charges were stored in the respective cellars, from where they were fed into the reloading (working) compartment through special devices - elevators. In the reloading compartment, shells and charges were reloaded into other elevators, which delivered them directly to the guns in the tower.
This scheme had two fundamental drawbacks. Firstly, the charges to the elevators were supplied in ordinary caps, which made them extremely vulnerable to even short-term exposure to fire. Secondly, no one bothered with the shutters between the ammunition magazines and the reloading compartment. Thus, the fire that broke out at the guns could easily go to the reloading compartment and then directly to the cellars, thereby causing their detonation.
According to the experience of the Dogger Bank, the Germans carried out two innovations. They introduced special flaps that automatically closed after the shells and charges were delivered to the reloading compartment, and fire-resistant canisters for filing charges. This turned out to be necessary and sufficient so that, despite the many battle damage to the main battery towers in Jutland, not a single artillery cellar of a battleship or battlecruiser Fleet the high seas did not explode.
The British, alas, were lucky in the battle at Dogger Bank - despite the fact that their battlecruisers received almost four times more hits than the German ones (not taking into account the Blucher armored cruiser, of course), not a single British tower was hit just as it happened with Seidlitz. As a result, the British did not see any reason to introduce any improvements in the design of their turret squads, and it can be safely assumed that the death of three British battlecruisers in Jutland was somehow connected with this.
Of course, I will not undertake to assert that if the Queen Mary, Indefatigable and Invincible were modernized in the model and likeness of the linear forces of the Hochseeflotte, they would certainly have survived. For such a statement, one still needs to know exactly the places and trajectories of hits by German shells, but it is absolutely impossible to get all this. Of course, if some German projectile managed to “pass” directly into the powder magazine, then the design of the turret compartments would no longer solve anything. But such a scenario is extremely doubtful, at least for the Invincible and Queen Mary, which were destroyed from relatively short distances, at which the shells still maintain a flat trajectory, so such a “penetration” looks unlikely.
In general, the version that the tragedy of the British battlecruisers was dictated precisely by the explosive nature of the design of their turrets has long become canonical, and I have no reason to refute it.
But how were things in this matter with the Russian dreadnoughts?
Very interesting information about this is contained in the book of the respected S. E. Vinogradov "The battleship" Empress Maria ", which I strongly recommend to any reader interested in history Russian fleet.
I would like to note that in this work, S. E. Vinogradov, of course, gives a description of the Black Sea dreadnoughts. But he also notes that the design of their turrets and turret compartments was extremely close, and the main difference was only an increase in the thickness of the turret and barbette armor. There were some other differences that allowed the battleships of the "Empress Maria" type to develop a better rate of fire than their Baltic "colleagues", but otherwise the designs were, if not identical, then extremely close to this.
Cases for semi-charges
So, let's start from the stove, that is, from the cellars of charges to 305-mm guns. The charges were gunpowder packed in silk caps with straps, for which it was convenient to pull these caps. Taking into account the fact that the combat semi-charge weighed 65,52 kg, the reinforced practical one - 49,14 kg and the practical one - 36,24 kg, this measure looks quite reasonable.
Semi-charges on Russian dreadnought battleships were stored in racks, and each was provided with a separate case “model 1909/1912”. This case was a cylinder 1 mm high and 323 mm in diameter, made of 320 mm thick steel. The functions of the stiffening ribs were performed by six annular protrusions, and from the inside the case had a layer of asbestos 1,6-3 mm thick so that the semi-charge did not come into direct contact with the steel case of the case.
The case, of course, came with a lid. It closed like this - in the upper part of the case there was a brass ring that created a gap between brass and steel and had 6 grooves. A special mastic was poured into this gap, which had a melting point of at least +90 degrees. and not corroded by sea water. The cover had such a shape that during installation its edge went into the gap, and then you just had to turn it all the way so that the corresponding protrusions on it fit into the grooves on the brass ring. For "turning" a special key was used. And the same key was used to open the case, after which the half-charge was removed from it with the help of the straps mentioned above.
Special attention should be paid to the fact that the case for semi-charges, except for cases of loading ammunition into the cellar, did not move with it, but remained on the rack. Thus, in a combat situation, half-charges were taken out of their cases right in the cellar: but what would happen if such a half-charge ignited?
Accident at Sevastopol
On the morning of October 17, 1915, work was in full swing in the turret compartments of the bow turret of the newest dreadnought. Five sailors reloaded 42 semi-charges in cases from the upper charging cellar to the lower one. As usual, nothing foreshadowed the tragedy, but when only three cases remained to be unloaded, one of them caught on the coaming of the hatch, slipped out of the sling and fell to the floor of the lower cellar from a height of about 3,5 m.
Later, it turned out experimentally that smokeless powder charges are prone to ignite when dropped from a height, and that they are guaranteed to ignite if they are dropped from about 9 m. But in this particular case, 3,5 m was enough - the gunpowder in the half-charge caught fire.
"Sevastopol" goes to Kronstadt, 1914
The result most of all resembled the work of a rocket booster: the lid of the case, of course, was immediately knocked out along with a certain amount of gunpowder, both of which were thrown back into the upper charging cellar, and the two sailors who fed the cases from this cellar were badly burned.
At this time, the case itself was spinning like a top at the place of impact, spewing a powerful stream of fire: the nearest rack with semi-charges peacefully lying in it, packed in cases, fell under its blow. Of the three sailors who were at that moment in the cellar engulfed in fire, one died immediately, and the other two managed to escape to the adjacent spare cellar. Both of them were severely poisoned by gases, which is why the next morning one sailor died.
When smoke was found on the Sevastopol bridge, the order to flood the cellars and turn on the irrigation was given immediately. But he was late - later the commission found that water began to flow even when the gunpowder in the ignited semi-charge burned out completely.
Subsequently, the commission examined 40 cases with semi-charges: thawing of the sealing lubricant was observed in all of them. Traces of burning were observed in 11 cases, and the same number of caps in the cases had traces of singed fabric. But still, the complete burnout of the semi-charge in the powder magazine did not lead to the ignition of the ammunition stored there, or to detonation. It is also interesting that the respected S. E. Vinogradov points out that this accident was not the first on the battleship, and that an incident had previously taken place, in all respects similar to the incident described above. It obviously also did not lead to the detonation of other powder charges.
Thus, it should be assumed that even if one or two half-charges ignited in the powder magazine of the Sevastopol or Empress Maria type battleships in a combat situation, this would hardly have entailed a catastrophe. And more of them could hardly have flared up, due to the design of domestic turret compartments, which will be discussed below.
Turret squads
The cycle of supplying ammunition to the gun, of course, began in the artillery cellars. On domestic dreadnought battleships in the 2nd and 3rd towers, they occupied 2 floors: the shell and under it - the charger. This was a very reasonable layout, since the most detonating ammunition was stored at the very bottom and was maximally protected from the effects of enemy artillery.
By the way, it will be said that the battleships of the classical layout were usually deprived of the opportunity to equip the charging cellars under the shells. This was because the ends where the towers are located are relatively narrow, and the closer to the bottom, the less space. But the charges are less dense and require more storage than shells, so placing them "on the floor below" required excessive elongation of the cellars, which was considered even more evil. At the same time, when the design of the ship made it possible to do this, it was done. So, for example, the placement of charging cellars under the shells was considered an advantage of the battleships Nelson and Rodney, in which the main caliber turrets were concentrated closer to the center of the hull.
Unfortunately, for the same reasons, the charging cellar "did not fit" under the shell cellar under the bow and stern turrets of the main caliber of domestic dreadnoughts - both Baltic and Black Sea. Therefore, in the aft tower, the charging cellar was traditionally located above the shell cellar, and the cellars of the bow tower had a three-story structure at all - charging, shell and charging again.
Green arrows point to charging cellars, red arrows point to shell magazines.
Briefly, the supply of ammunition to the tower looked like this. Through the lower charger, the projectile and semi-charges fell into the reloading compartment, where they were unloaded and placed on the charging table. Then they were reloaded into the upper charger, which already delivered the shot to the gun. Accordingly, there were two chargers for each turret gun - upper and lower.
Supply of ammunition
So, as mentioned above, the semi-charge was removed from the case with the help of appropriate straps and fit into the feeder, called the feeder. The latter delivered the charge to a special charging table, where he laid out. For the lower cellar of the bow tower, the route was longer - it was transported on a special lift to the upper cellar, and from there to the feeder and to the charging table, which was the same for both "floors" of the cellars where the semi-charges were stored.
Above the cellars was the reloading compartment. The ammunition was transported there by the lower charger, which was a metal box with three compartments for a projectile and two semi-charges, respectively. At the same time, the lower charger was made “decoupling”: the projectile compartment could move separately. This was necessary, since the projectile and charges were fed into the loader on different "floors" of the turret compartments, and it did not make sense to do this sequentially to save time. Instead, the charger was uncoupled, loaded with ammunition, and then, again "hooked", was fed into the reloading compartment.
Judging by the descriptions given by S. E. Vinogradov, it was here that the “chain” of supplying ammunition from the cellars to the guns was interrupted. Unfortunately, the respected master, stating the fact of such an interruption, does not give technical details, mentioning only the presence of “flaps, shutters”. But it is easy to assume the presence of flaps or hatches that closed immediately after raising or lowering the lower charger.
After the charger moved to the reloading compartment, its explosive contents were removed from it and placed on the charging table. Unlike the tables located in the cellars, this one was the same for both shells and semi-shots. Having unloaded, the lower charger went back to the cellars.
This was followed by the procedure for loading ammunition into the upper charger. It, unlike the lower one, was made non-releasing. Its lower "floor" was intended for the projectile, the upper two - for semi-charges. Of course, the procedures for moving “lower charger - table - upper charger” were mechanized, here a special rammer helped the sailors: it is, in principle, possible to turn the semi-charges manually, but moving 470,9 kg shells was clearly beyond human strength.
The upper charger, having received its deadly load, delivered it to the gun and mated with its swinging part. Thus, not only was it possible to ensure loading at any elevation angle of the gun, but also to carry it out with continuous tracking of the gun behind the target. Simply put, the stabilization of artillery mounts had not yet been invented, as well as accurate inclinometers that ensured the firing of a shot at the time the ship was on an even keel. Accordingly, the gunner was forced to constantly "follow" the target, combining the angle of vertical aiming of the gun with what the officer in charge of artillery fire asked. Loading guns on domestic dreadnoughts did not interfere with this process.
And it was carried out quite simply and clearly - after the gun was mated with the charger, the projectile tray opened, it rolled out so that its axis was aligned with the axis of the barrel, after which the chain breaker sent it. Then the semi-charge tray was opened, and everything was repeated. After the second half-charge hit the gun, the charger disengaged and fell down into the reloading compartment for a new shot ...
Ready to march and fight
At sea, if there was a threat of meeting with the enemy, they prepared for battle like this. The guns were loaded, with one shot for each gun in the upper loader, one more on the table in the reloading compartment, one in the lower loader and one on the cellar tables: a total of five shots.
As a result, each tower of the dreadnought was capable of firing 15 shots, "having only orderlies on the marching schedule." Accordingly, the dreadnought was ready to open intense fire at any moment, even before the artillery cellar teams took their places on alert.
Conclusions
According to the description of the respected S. E. Vinogradov, the turret squads of domestic dreadnoughts were extremely well protected from fire. In fact, the lessons that the Germans had to "learn" during the battle at Dogger Bank, and the British - during the Jutland, were learned by us even before the start of the First World War.
The metal chargers in which the ammunition was transported protected the semi-charges well from the short-term exposure to hot gases generated during the explosion of an enemy projectile: unless the projectile exploded so close that the box was destroyed. This decision dramatically reduced the likelihood of fire in comparison with the transportation of semi-charges without any protection.
Caps with gunpowder were outside the charger only during the loading procedure, on the charging table of the reloading compartment, and also during the supply from the cellars to the lower chargers. But the ignition of the semi-charge at the moment of reloading the gun could hardly cause the spread of fire into the reloading compartment. Even if this happened, and the charges in it ignited, then, taking into account the dampers blocking access to the cellars, the fire could hardly have gone lower.
But let's say an enemy shell pierced the 125-mm Sevastopol upper belt and the 75-mm barbet behind it and exploded, igniting the half-charges ready for loading on the upper chargers in the reloading compartment at the moment when the corresponding "claps" are open (it just so happened, that just at that moment one of the lower chargers was lowered into the cellars, for example). Even in this case, the chances of fire penetrating into the cellar, located a few meters below, are not too great. Suppose, however, that the burst of an enemy projectile dropped one of the ignited half-charges directly into the open "slam", and it fell straight onto the table, where other half-charges were waiting for loading into the lower charger. What then?
Even in this case, the maximum possible is the ignition of several half-charges, and not in the cellar itself, but in the supply pipe of the tower. Even if, by some miracle, there are six semi-charges on the table, and they all light up, it is far from certain that the flame will be able to “reach out” to the ammunition storage racks.
Of course, the description of the Seidlitz fire comes to mind, in which a tongue of fire “as high as a house” rose above the towers. But you need to understand that as many as 6 tons of gunpowder ignited on the German battlecruiser, while even in six semi-charges for the 305-mm / 52 domestic gun it was slightly less than 400 kg. And even if the flame still reached the cellars, then, as we can see from the experience of Sevastopol, the cases in which the caps were packed confidently protected gunpowder from short-term exposure to even a very powerful fire jet. At the same time, the storage of semi-charges outside the cases was strictly prohibited and not practiced.
Thus, it can be assumed that the weak armor of the turrets and barbettes of the Sevastopol-class battleships was to a certain extent compensated for by the successful design of the turret compartments, which minimized the likelihood of disasters in the manner of those that befell the British battlecruisers in the battle of Jutland. It was to be expected, of course, that in the event of a hypothetical battle between the Sevastopols and German dreadnoughts, the latter hitting the towers and barbettes of Russian ships would lead to heavy damage and no less heavy losses, which could well have been avoided by strengthening their armor protection. But still, catastrophes caused by the detonation of powder magazines, perhaps, should not have been expected.
Here, of course, a respected reader may have a question: what about the “Empress Maria”, and why did she explode if everything was so great with the cellars? But let's not forget that the cause of the death of this ship was a fire that arose in the magazines of ammunition. The causes of this fire have not been established so far: sabotage is not excluded. In the case of the Empress Maria, we are talking about a long-term effect of fire on the charges stored there, and not a short-term one, which was to be expected when the ship received combat damage.
Information