Starting with the smashing of Dunkirk

Chapter 139 Destroy Dover Port Forever

Before firing, the artillery groups at Cape Grêmio in Porto Calais were divided into five groups as planned.

During combat, these cannons would also fire in groups, alternating to avoid interfering with the observation of the impact points—at this time, the technology of dye shells for naval main guns had not yet been invented. When multiple warships or multiple turrets fired simultaneously, if the shells were widely dispersed, it would be difficult to distinguish which water column was caused by which shell's explosion, which would also affect the efficiency of subsequent fire correction.

Therefore, before the war, Colonel Keitel, Lieutenant Colonel Loeb, and several other lieutenant colonels in charge had already discussed and planned the group divisions:
All eight 380mm armored turrets were divided into three groups according to a 3/3/2 configuration. Each group would select a target before firing, with each group firing every 10 seconds. In other words, each turret would fire a round every 30 seconds, but initially only group A would fire, followed by group B after 10 seconds, then group C after another 10 seconds, and so on.

This 3/3/2 division is not arbitrary, but based on the natural distribution of these turrets during construction and installation.

During construction, due to the terrain limitations of the white cliffs at Cape Greene, these artillery units were initially divided into three relatively concentrated positions. The goal was to concentrate the artillery fire on one ship from each position, while dispersing the guns would maximize their effectiveness.

In battles between battleships, this "semi-salvo" can easily introduce new errors. This is mainly because the warship will roll and sway after the main guns fire, causing the actual elevation angle of the battleship's main guns to fluctuate constantly, affecting accuracy.

However, shore artillery does not have this disadvantage because the ground does not shake. The "half-volley" tactic can fully utilize its advantages and completely avoid its disadvantages, so it is simply a waste not to use it.

Apart from the three groups of armored turrets, all five 380mm railway guns were grouped together in one group, and all 15 280mm railway guns were grouped together in another group. Each group shared preset parameters and firing calibration data.

Meanwhile, considering that Dover Harbour has two main anchorages, including the main anchorage in Dover Harbour and the Folkestone anchorage a few kilometers away, pre-war planning required all three armored turrets to target the main anchorage in Dover Harbour, while all railway guns were to aim at the secondary Folkestone anchorage.

Two airships will also be hovering at an altitude of 4 meters, providing observation and firing correction for the Dover and Folkestone anchorages, 20 kilometers away, respectively.

随着凯特尔上校的“开火”指令装甲炮塔群A组的3座6门380毫米炮，立刻发出轰天巨响，朝着多佛港主锚地的预设泊位坐标射出6枚750公斤重的穿甲弹。

Meanwhile, on the other side of the railway gun corps, two 380mm railway guns also fired two 750kg armor-piercing shells at the preset berth coordinates of the Folkestone anchorage. The railway guns were too slow to reload, taking more than four minutes to fire a round, so they could not fire all five guns at once, but could only fire one or two rounds at a time, slowly calibrating the firing.

The shells flew through the air with a sharp whistling sound that tore through the sound barrier, taking nearly 80 seconds to cover a distance of 36-38 kilometers. If the opposing warship was traveling at 20 knots, that would be enough time for the enemy ship to travel half a nautical mile.

Fortunately, the opposing warships were all anchored, which completely eliminated this major factor affecting the hit rate.

80秒的炮弹飞行时间，4轮就要320秒，所以5门380列车炮按2/1/1/1分组，刚好确保最后一轮的炮弹落地时，第一批开火的2门380列车炮又装完弹冷却好了。

至于280炮，也可以按5门一组、分成3组、每组间隔60秒开火，因为280列车炮的装填周期只有3分钟，分三组就够了。280炮的水柱也和380明显不同，不会影响观测分辨。

Although the 280mm gun had a relatively small caliber and propellant charge, it could still reach a considerable distance when tilted up to 45 degrees, as Demania's 280mm guns all started with barrels of 50 calibers or more. In contrast, the longest of those 380mm guns was only 45 calibers.

Thanks to its longer barrel and longer acceleration travel, the Type 280 can, with modifications to the breech chamber and the adoption of a high-charge firing mode that disregards barrel life, barely reach the edge of a target 35 kilometers away. However, this firing method drastically reduces the barrel's accuracy and lifespan to the point where it becomes unusable after only about 100 shots.

然后只能拉回去扩膛重新划膛线，扩两次后就彻底废了。第一次扩膛后可以装305毫米口径的炮弹，再扩一次就得装320毫米的炮弹。而且装305炮弹时寿命只够再打60发，扩到320后只能再打40发。

With both breech-expanding operations combined, the total number of shots fired throughout its lifespan is only around 240. Furthermore, the Empire hasn't yet prepared 320mm shells; fortunately, such shells have never actually been used, so there's no need to open a separate production line.

The idea of ​​"ultimately expanding the barrel to 320 mm to make the most of the remaining lifespan" was also proposed by Colonel Lelouch. It was met with opposition from many people, who said that the Empire did not have a production line for 320 mm shells and that it was not worth wasting resources and production capacity to open a separate production line for a cannon that might be partially scrapped in the future.

However, Colonel Lelouch insisted on including this plan as a backup, stating that a separate production line wasn't necessary; it was merely a backup technical demonstration. Lelouch knew that the Italian naval gun company, Oto Melara, initially started by copying the Demania 305mm gun. Later, after the outbreak of World War II, they also worked on using older guns with increased propellant charges and subsequently enlarging the barrels, resulting in the 320mm gun (12.6 inches). This design was used in the post-war refitting of the Andriadria-class dreadnoughts, and a shell production line was even established.

Historically, the Italians may not have excelled in other areas, but they have always been adept at increasing the explosive charge of cannons regardless of their lifespan and in retrofitting them to maximize their potential. They have a wealth of practical experience in this area. Otherwise, the Veneto-class "KY cannons" would not have been developed during World War II.

Since Otto Melara has already conducted research in this area, the Empire might as well include this backup technology route in its planning. Once Italy is destroyed, these technologies can simply be used directly, right?
This is called waste utilization; it avoids wasting any resources.

When Lelouch made this plan, Vice Admiral Hipper of the Navy was also dumbfounded when he saw these notes during the final approval of the plan, but he still secretly approved it in the end.

Lelouch, that brat has some nerve! This is utter contempt for the Italians.

In modern terms, it's like viewing the other party as an experience pack for "leveling up and looting." It's like a World of Warcraft undead player controlling a Death Knight with level 3 Death Coil, excitedly shouting "My skeleton!" upon seeing a human peasant.

Everything was arranged so meticulously; all the effort was spent on the pre-war staff preparation phase.

It can be said that one minute on stage requires ten years of practice off stage.

……

"Boom! Boom! Boom!" The first round of loud explosions occurred near the main anchorage of Dover Harbour. The shells generally traveled nearly 2 kilometers further before exploding in the harbor's storage yards and warehouses, without damaging any ships on the berths.

"Lower the muzzle by at least 3 degrees! Test fire again! It went too far! A full two kilometers. It veered at least 600 meters to the left."

After observing the impact point of the shells, Colonel Keitel immediately flashed a spotlight signal towards the command post of his own artillery group, which was more than ten kilometers away.

In the rear artillery command post, observers were using high-powered telescopes—fixed high-powered telescopes with a speed almost twice that of ship-mounted rangefinders—to observe their own airships and ensure that every light signal sent back by the airships could be accurately interpreted.

In this way, one spotlight emits the light, and a high-powered telescope watches it closely to ensure that the spotlight flash can be clearly seen from more than ten kilometers away.

Upon seeing the signal, which was two kilometers away and 600 meters to the left, the gunners immediately began to lower the gun's elevation angle and simultaneously fine-tune the left and right aiming positions by one degree and several tens of degrees.

The distance to the enemy port anchorage is too far, with an error of about 600 meters, and even a slight adjustment of just over 1 degree in the azimuth angle is needed.

Soon, the second and third artillery groups also began firing in sequence at 10-second intervals. These artillery groups had already lowered their muzzles somewhat, and the range error was indeed reduced.

Every time, even though the aiming was precise, the target would always veer to the left. Even after taking into account the wind force and speed of the day, this error could not be eliminated.

While Colonel Keitel was relaying messages from the airship to the rear to minimize errors, he couldn't help but wonder after the message was finished:
"The left and right azimuth angles are clearly aimed directly at the berths pre-surveyed on the map, so why are they all veering to the left? Wind force and direction were taken into account, and there wasn't much wind this morning..."

After firing two or three more rounds and gradually reducing the error, Colonel Keitel finally remembered a few casual reminders that Commander Lelouch had mentioned when the plan was first formulated.

"...We had never considered such a high-angle trajectory to fire at a target 35 kilometers away. The apex height of previous artillery shell trajectories had not exceeded 1 meters."

However, this issue needs to be considered when attacking targets more than 35 kilometers away. The upper atmosphere may be too thin, so air resistance may suddenly decrease at the highest point of the projectile's trajectory, and the projectile's air friction stall will also decrease, so the final actual range may be farther than expected.

At the same time, we are used to viewing the Earth's atmosphere as a soft spherical shell that rotates with the Earth. However, once we reach the thinner regions of the upper atmosphere, the friction between air molecules will be greatly reduced, which may not be enough to make the upper air rotate at the same speed as the lower air.

What if, at that point, the lower atmosphere can keep up with the Earth's rotation, but the upper atmosphere rotates slower? Wouldn't that be equivalent to the upper atmosphere exerting a crosswind force against the direction of the Earth's rotation on the projectile at its apex? Therefore, it's quite normal for high-angle projectiles, as long as they reach an altitude of over 1 meters, to have a slight margin of error in the opposite direction of the Earth's rotation.

When Keitel was planning this project, he heard these anecdotes from Commander Lelouch, but he only listened casually. During the actual maximum elevation firing tests of the cannon, some errors were encountered, and they considered calibrating it. However, because the firing direction varied in each test, they never accurately recorded all the actual conditions.

Because the Coriolis effect varies slightly depending on the launch direction of the projectile. The barrel life of these artillery pieces is also quite valuable, and there aren't enough ammunition to repeatedly test coordinates.

Fortunately, this practical exercise also included high-altitude firing calibration from an airship, providing excellent visibility, and there was still time for on-site calibration.

At least having this in mind makes the reaction much faster than having no concept at all—originally, in Earth's history, the Demanians didn't understand the impact of the thin stratosphere and the Coriolis effect on the trajectory of the ballistic missile until the end of 1917 when they developed the "Paris Cannon" to bombard Paris 120 kilometers away.

All of these shortcomings can be addressed today.

By the fifth round of calibration, the additional errors introduced by the Coriolis effect and the thin upper atmosphere had been largely corrected.

……

At the same time, inside Dover Harbor.

Three minutes ago, when the first round of shells landed, everyone in Dover Harbor was startled and immediately ran out of their houses to look around and search for the source of the explosion.

Most people even thought they had been attacked indiscriminately by airships at extremely high altitudes.

"General Hood! Something terrible has happened! The port area has been attacked by Demacian airships! It's estimated that they dropped 100-kilogram aerial bombs over a large area!"

In the Straits Fleet headquarters at Dover, the office door of Rear Admiral Horace Hood, the fleet's deputy commander, was flung open, and several officers on duty burst in, panting and shouting incoherently.

"Air raid? Which direction? Have you spotted the airship?" Major General Hood suddenly stood up, ran to the window, and looked outside.

The headquarters was located several kilometers away from the port berth area, so it was normal that the sound of the explosion could not be heard.

The adjutant immediately pointed frantically to the distant berth area, and Major General Hud quickly grabbed his binoculars and carefully searched that area. Sure enough, within a few dozen seconds, he saw several faint flashes of light, followed by plumes of smoke. Judging from the explosive yield, it shouldn't have been a very heavy bomb.

Major General Hu quickly pondered for several seconds and then issued several orders:

"Immediately order all ships to heat up their boilers and prepare to depart from port, while simultaneously maintaining air defense! All shore-based anti-aircraft guns within the port area are also to freely search for targets and fire freely! However, once a target's location is detected, it must be reported immediately!"

"Call other major bases and ask if they have experienced similar airstrikes!"

After some confirmation, which took three or four minutes, it was learned that enemy airships had indeed been spotted in Harrich Harbor.

Meanwhile, Hood learned over the landline that enemy airships were heading towards the berth at Harrich Harbor. They had likely accumulated navigational errors during the night and would need to adjust their course and head towards the port as soon as visibility improved at dawn. However, Harrich Harbor was already in complete chaos, even before it had been bombed, as everyone was trying to prevent the airships from approaching.

(Note: This refers to the bombing in the early morning of July 28th, which is mentioned in Chapter 137.)

The reason why Hood and his men failed to realize for so long that the enemy was shelling rather than attacking from the air was not entirely their fault—because normal shelling would produce a sharp whistling sound as the shells cut through the air.

However, if you understand a little physics, you'll know that the so-called whistling sound of artillery shells cutting through the wind is actually based on a physical principle called "sonic boom".

A sonic boom only occurs when a projectile's speed exceeds or is very close to the speed of sound, about to break the sound barrier.

During World War I, the muzzle velocity of a normal large-caliber naval gun would be at least 700 to 800 meters per second, which is more than twice the speed of sound.

However, as the shell flies, it is rubbed by air resistance, and its speed will gradually decrease. At the maximum range, it is often rubbed down to subsonic speed - this is only possible with artillery fire of more than 35 kilometers.

For example, the VSS, the "catapult" in PUBG, is a subsonic bullet gun, so it is extremely silent. When you are hit by a VSS in PUBG, you have no idea which direction it came from.

In fact, during the Paris bombardment in 1917, the Franks were subjected to shelling for a long time before they confirmed it was artillery fire. Initially, to prevent public unrest, the authorities claimed it was aerial bombardment.

Although the citizens of Paris never saw the airship, they couldn't refute the argument that it was because they couldn't hear the sonic boom of the supersonic shells.

The situation in Dover is similar now. A shell with an initial velocity of over 700 meters per second has a terminal velocity of only over 300 meters per second, leaving only 45% of its velocity. Armor-piercing shells have even less than 20% of their kinetic energy (a junior high school physics formula states that kinetic energy is proportional to the square of velocity).

Having traveled such a long distance, the shells' armor-piercing capability was significantly reduced. Fortunately, they were almost impossible to hit the main armor belt on the sides, and could only land on the warship's horizontal deck at an angle of about 50 degrees.

Battleships during World War I generally had relatively thin horizontal armor because they were designed for close engagements. Even a 15-inch armor-piercing shell with only 2% of its kinetic energy remaining could still penetrate it.

"Boom!" With the sixth round of shelling, the Bellerophon-class battleship "Reckless" was hit on the top by a 380mm shell. The shell tore through the horizontal armor and the dome armor and exploded in the lower compartment of the bow, leaving a large hole in the bow of the entire warship.

It was only then that the Royal Navy commanders, led by Rear Admiral Hood, realized the source of the attack.

"It was enemy battleship shelling! Not an air raid! Small bombs weighing a hundred or two kilograms couldn't possibly have that armor-piercing capability!"

Their previous assessments were all based on the explosive yield of the blast. Officers near the front-line explosion points also consistently reported the blast power as that of small to medium-sized aerial bombs.

But small and medium-sized aerial bombs don't have that kind of penetrating power! This is probably a specialized armor-piercing projectile with a pointed nose cap! It's specifically designed for armor penetration!
Rear Admiral Hu immediately used radio to command and request the patrolling light vessels of his own side to report on whether they had seen enemy warships being deployed from the opposite shore, especially the eastern port.

However, radio communication is much slower than telephone communication. Even the most urgent telegram would take five or ten minutes to send a round trip.

The fleet officers and soldiers in the port were bombed for several more minutes, like headless flies.

在“鲁莽号”中弹后，对着“鲁莽号”轰击的敌军炮群射速陡然就变快了数倍，从原先80秒一轮提到了30秒一轮。3分钟内又有2枚380炮弹分别炸中了主舰桥和正前方的1号炮塔。

Almost all the shells were aimed at the bow of the HMS Reckless, which was unavoidable—the HMS Reckless was currently docked facing north-south. In a normal battleship exchange, both sides should engage the enemy with their broadsides, but now they could only face the enemy bow to bow.

The ship's bow-facing orientation actually increases the enemy's chances of hitting it: as is well known, it is easy to adjust the left-right error when firing at long range, but difficult to adjust the near-far error.

When shelling at a distance of 35 kilometers or more, with identical firing parameters, the final impact point of the shell may fall within an error range of 150 meters wide and 400 meters long. By positioning the warship bow towards the enemy guns, it actually provides the shell with a larger projected cross-section.

The main gun turret of the "Belle-Lophon-class" has 11 inches of frontal armor, which is enough to make it immune to 15-inch armor-piercing shells with a terminal velocity of only 300 meters at such a long distance.

Unfortunately, the armor on the top of its turret was only 4 inches thick. A shell flying from 35 kilometers away would have penetrated its skull at a 50-degree angle.

The armor-piercing shell violently tore open the top cover of the twin-mounted 305mm main gun turret, exploding inside and blowing the turret off its surface. Had the main gun turret not been without spare ammunition while the ship was moored, the shell detonation alone would have been enough to seriously damage the warship.

Meanwhile, HMS Magnificent, a sister ship of the same type berthed next to HMS Reckless, finally took its first hit from the continuous fire of the other three 380mm turrets.

The ship was hit on the bow side again, but this time the shell landed near the main gun turret on the port side, piercing the deck armor and also blowing through the main gun turret ring and the side wall of the ammunition well.

Countless bearing steel columns flew outwards from the side of the ship, and the entire port forward turret was blown up and tilted several degrees to the left, looking like it was about to collapse.

"Report! It's not enemy battleships firing! It's coastal defense artillery firing from the direction of Calais Port across the sea!"

"The 4th Destroyer Reconnaissance Squadron is currently located 10 nautical miles south of the port and has observed muzzle flashes at the White Cliff Bay depression at Cape Greene, 14 nautical miles southeast of the port!"

It wasn't until both dreadnoughts were hit by shells and badly damaged that the Strait Fleet finally pinpointed the exact source of the attack.

By this time, a full ten minutes had passed since the first shell landed.

"What? They're shelling across the sea?!" When Major General Hu De heard this, he was so shocked that he jumped up, not even caring that his hat had fallen to the ground.

His hands gripped the desk so tightly that he seemed to be trying to dig marks out of the oak with his fingernails, unaware that his nails were aching.

"Evacuate the fleet at top speed! All warships, start fires and set sail immediately! Move out of port immediately! Abandon Dover anchorage!"

"All combat reconnaissance aircraft have taken off, sparing no effort to attack and interfere with the enemy's airships over the strait! It must be those two airships providing coordinate calibration errors to the coastal defense artillery on the other side!"

Unfortunately, even with the Britannian Navy's vigilance, the Dover harbor, being close to the front lines, meant that the ships' propulsion systems were generally not completely shut down. Setting sail under these conditions would take nearly an hour. Furthermore, with so many ships, the departure channels would be congested, meaning that dispersing the fleet would actually take at least two hours.

Being bombarded by the enemy for two hours while stationary, even if the accuracy of ultra-long-range artillery is very low, as long as there is aerial observation and fire correction, two hours is enough to do a lot of things.

此后10分钟，加莱方向的3座双联装380装甲炮塔，对着“鲁莽号”足足倾泻了120枚380炮弹，取得了直接命中9枚的成绩。

The three main gun turrets at the front of the "Reckless" (one directly forward and one on each side) were all smashed through by the head-on attack. Although the conning tower of the main bridge could not be penetrated at this distance, the main bridge was not that thick all over.

Except for the conning tower, any part of the bridge that was hit by the bomb was bound to be penetrated. In the end, after a series of heavy blows, part of the main bridge was even blown away and fell into the sea.

The foredeck was also pierced by three large holes. The force of the explosion tore through the bow armor from the underwater inside, causing a large amount of seawater to rush in. Later, because the impact area was very concentrated, even the armor-piercing shells continued to penetrate into the bow, which had already been blasted open by the previous shells, and even blasted through the bow keel and created a hole in the bottom of the ship.

The three main gun turrets at the front of the entire "Reckless" were completely destroyed, and the former compartments in the core area were also completely destroyed and flooded. Even the head of the keel was broken. It can be said that the entire bow was completely blown up and was beyond repair.

The stern was thus raised high and the bow plunged into the water. The twisted hull even caused the surviving keel to twist, because the keel simply could not withstand such a complete self-weight torque for an extended period of time.

Even if you repair this kind of thing, it's still useless. Just dismantle the two rear turrets for spare parts, remove the other instruments and equipment, and melt down the hull as scrap steel. That way you can barely recover 20-30% of the ship's value.

Although the "Magnificent" was hit 6 minutes later than the "Reckless," there is no order of precedence in learning; the one who achieves it first is the one who comes first.

The "Magnificent" was ultimately hit by only 8 shells, 2 of which were spared. However, the ammunition silo of the forward main gun turret was continuously bombarded head-on and torn open from the front, eventually causing the forward main gun ammunition magazine to explode and sink directly to the bottom of the sea.

The explosion on the HMS Magnificent even affected a nearby destroyer and several tugboats and barges, sinking these innocent vessels as well.

This kind of death would be absolutely impossible in normal naval warfare—the reason why the ammunition silo of the forward main gun magazine was so easily torn open was entirely because the armor in the non-core area of ​​the bow was very thin. Therefore, an armor-piercing shell that hit the bow deck could leave a huge hole in the bow.

While the armor of the ammunition silos and magazines is thick, the thickening is concentrated along the port and starboard sides, not the front. This is because, under normal circumstances, the front is already shielded by the ship's own bow, which provides several tens of meters of protection; there's no need to defend that direction.
If even this area needs to be defended, wouldn't that mean the front dozens of meters of the warship would be completely penetrated? No designer would waste tonnage and armor on such a tricky angle that would be impossible to penetrate in actual combat.

But today's battle is at a distance and angle of attack that are unprecedented in a century. Who can we complain to?
The two dreadnoughts were thus unilaterally and utterly sunk without any suspense or resistance.

(End of this chapter)