The panokseon warships advancing up the Yalu River were vessels scheduled for retirement after the mass deployment of Haeeung-class ships had taken over their patrol duties in the West Sea and South Sea archipelago regions.
However, with Liaodong’s suspicious movements, they had returned to the front lines.
“While the Yalu River is a natural defensive line, it also hinders us when we’re attacking.”
“We need a means to solve this.”
In the process of finding suitable means, the panokseon caught their attention.
“This looks good.”
-The panokseon’s greatest advantage is being a flat-bottomed vessel. Flat-bottomed vessels have flat bottoms and shallow drafts.
-The relatively shallow draft allows for some movement even in rivers. In the case of panokseon, if ballast is reduced, they can advance upriver at least as far as Insan Fortress without difficulty.
-The flat bottom maintains horizontal stability even if grounding occurs accidentally or intentionally. If this advantage is well utilized, it can serve as both an excellent fixed position and a pontoon bridge for river crossing.
-One panokseon carries 26 guns including Type-Eul war wagons. If at least ten ships can enter, they can become a sufficiently powerful force.
Following this decision, the panokseon retirement was temporarily suspended, and they were concentrated in Gyeonggi and Hwanghae naval bases.
After gathering the panokseon thus, the Joseon navy simultaneously conducted extensive repairs and various modifications.
And as soon as battle broke out at Insan Fortress, they deployed these prepared panokseon.
The panokseon fleet that first gathered at the Yalu River estuary began preparing to advance upriver.
“Dump the ballast!”
“Yes, sir!”
Following the captains’ orders, soldiers began removing concrete blocks laid in the ships’ bottoms and throwing them into the sea.
After confirming the panokseon had become appropriately lighter, the captains issued their next orders.
“Start the engines!”
“Yes, sir!”
Following the captains’ orders, the embarked stokers began operating the steam engines.
***
The crowning achievement among modifications made for this battle was the installation of steam engines.
Rather than large engines like those mounted on sailing ships plying the northern routes or iron horses, they installed one small steam engine from artillery towing vehicles.
Mounted in the rear of the panokseon’s first deck, the steam engine had a power distribution device containing over ten gears. The distribution device had two long iron rods attached, which descended at an angle toward the water surface. At the ends of these angled iron rods entering the water were propeller-style thrusters.
It was a makeshift device, as there hadn’t been enough time to modify them like the sailing ships operating in the north.
However, after creating and testing a prototype, it received an evaluation of being usable. According to experiments on the Han River, though slow, it steadily advanced upstream.
“With oarsmen too, it’s enough!”
***
As the steam engines’ pressure rose sufficiently, the stokers operated the levers to activate the power distribution devices.
As the screws began turning, the panokseon started advancing up the Yalu River.
Their target was Insan Fortress, 80 li (approximately 32km) away.
***
While the panokseon fleet formed Joseon’s left wing, cavalry formed the right wing.
The scale of cavalry mobilized for this battle was two divisions (부(部, bù = division)), about 35,000 troops. Though the numbers might seem weak to call it a great army, in terms of combat power alone, it could be called supreme.
The reason for this assessment was that they were cavalry and operated mass artillery.
***
According to Joseon’s military reforms planned by Sejong and seasoned by Hyang, artillery was the core of Joseon’s military power, supported by gun troops and cavalry.
-Considering Joseon’s national economy, troops cannot be increased recklessly.
-Though forces are supplemented through reserve mobilization when wars threatening national survival occur, during normal times maximum combat power must be extracted from appropriate-sized forces.
-Considering the above conditions and Joseon’s expanding territory, units combining powerful mobility and firepower must become the military’s core.
Following these decisions, Joseon’s Land Defense Forces were divided into two.
One comprised those stationed in strongly built fortresses like Insan Fortress, and the other was cavalry.
The common point between these two groups was that they operated mass artillery.
Whether fortress garrisons or cavalry, artillery was the core of combat power.
***
As soon as Liaodong’s movements were detected, Joseon’s cavalry moved quickly. One division continued northward. Their mission was to strike Liaodong’s rear by beginning invasion from the northeastern region.
Two divisions moving to strike the flanks of Liaodong forces battling at Insan Fortress sprinted along military roads built on the Gaema Plateau, then circled around south of Mount Baekdu to cross the Yalu River.
After crossing, the Joseon cavalry sprinted at full speed toward Insan Fortress along the north bank of the Yalu River.
***
Thus arriving, the panokseon fleet and Joseon cavalry began striking the Liaodong army’s left and right flanks.
About 30 panokseon had advanced upriver. Among them, 10 formed a single line in the middle of the Yalu River.
Their targets were Liaodong forces crossing the river. Therefore, the ships assigned this mission carried 60 Type-Eul war wagons instead of naval guns.
A total of 600 Type-Eul war wagons targeted Liaodong forces gathered on both riverbanks and in the river.
Of the remaining 20 ships, 5 advanced along the south bank while 15 advanced and settled along the north bank.
The 400 guns and 80 Type-Eul war wagons loaded on these 20 panokseon settled along the riverbanks targeted Liaodong forces gathered along the banks and nearby.
“Open fire!”
At the orders of captains standing tall in the panokseon towers, the guns and Type-Eul war wagons all spewed fire.
Kaboom!
Ratatatata!
The naval The cannons fired by the panokseon’s guns and the rain of bullets from Type-Eul war wagons began instantly crushing the Liaodong forces.
“Uwaaah!”
“Aaagh!”
Liaodong forces fell screaming under Joseon’s attack.
Those suffering the most devastating casualties from the Joseon naval attack were Liaodong forces crossing the Yalu River. Liaodong soldiers staggering against the natural obstacle of water fell to Type-Eul war wagon fire, and the Yalu’s waters instantly began turning bright red.
A similar situation unfolded on the Liaodong army’s left flank.
Kaboom!
The cannons fired by Joseon cavalry began thoroughly destroying the Liaodong army’s left flank.
Ratatata!
As soon as the cannons volley ended, Joseon cavalry’s volley followed.
“Argh!”
“Counter-attack! Return fire!”
Though Liaodong’s left wing greatly wavered after receiving Joseon cavalry’s devastating strike, Liaodong commanders soon regained their senses and ordered counterattacks.
At the commanders’ orders, Liaodong soldiers aimed matchlocks and bows at the Joseon cavalry.
However, it was a futile effort.
The range of their matchlocks and bows was pathetically short compared to Joseon cavalry’s Type-Eul rifles.
At Insan Fortress and surrounding trench zones, they could engage in firefights within matchlock range using friendly artillery support and terrain features like craters created by explosive shells.
But now they were fighting in open terrain.
This was the optimal place to properly utilize the Type-Eul rifle’s superior range.
This was Joseon’s lethal strike after deceiving about the range of Type-Gap and Type-Eul rifles through all sorts of methods until now.
The Liaodong army’s left flank began gradually crumbling under Joseon cavalry’s concentrated attack.
As the enemy lines began collapsing, Joseon cavalry continued bombardment and rifle fire while gradually advancing.
As this collapse and advance repeated, the hole torn in the Liaodong army’s left flank grew increasingly larger.
Then suddenly, Joseon’s rifle fire stopped.
When the gunfire ceased, elderly Jurchen warriors shouted.
“Prepare for cavalry charge!”
“Prepare for cavalry charge!”
Before their shouts even ended, Joseon cavalry’s charge began.
Thud-thud-thud-thud-thud!
As thousands of cavalry charged at once, the heavy rumbling shook the ground.
Following orders, Liaodong soldiers formed battle formations and gripped matchlocks and spears, swallowing dry saliva while awaiting Joseon’s charge.
As the cavalry’s distinctive long spears aimed at them grew larger, soldiers with matchlocks took aim.
In that moment, what struck them was the cannons.
Kaboom!
The battle formation instantly collapsed from the cannons explosions, and following that, Joseon cavalry’s long spears pierced through them.
“The Joseon bastards’ feet are tied! Strike!”
“We must tie their feet to stop their second attack!”
“Uwaaaah!”
Though Joseon cavalry’s charge broke through the first defensive line, the cavalry’s speed had decreased. At this, second line commanders ordered their men to catch the Joseon cavalry trying to break out to the sides.
Speed was cavalry’s lifeblood. Catching them would make them lose their greatest weapon, and could also stop the approaching Joseon cavalry’s second strike.
At this, Liaodong soldiers charged toward nearby Joseon cavalry with battle cries.
“No! Retreat! Retreat!”
Elderly Jurchen veterans shouted to fall back, but it was too late. The weapons Joseon cavalry truly favored began spewing fire.
Bang-bang-bang-bang!
The six-shot Type-Gap horse pistols began firing as if possessed, and surrounding Liaodong soldiers fell. Seeing this, other Liaodong soldiers hesitated, and without missing this opening, Joseon cavalry broke out to the sides.
As the first attack wave broke free, the second attack wave descended upon the Liaodong forces.
***
Under attack from Joseon cavalry and navy, the Liaodong army slowly began to crumble.
The Liaodong forces that had already crossed the river and were attacking Insan Fortress’s trench lines fell into panic, from soldiers to commanders.
The Joseon trenches they had felt were about to break now suddenly filled with new Joseon soldiers pushing them back.
The reinforcements meant to support them were becoming fish food in the middle of the Yalu River.
Pillars of fire were rising everywhere from their main camp across the river.
“This won’t do! Let’s run!”
“Retreat! Retreat!”
Soldiers who realized things had gone wrong began turning and fleeing.
“Stop!”
“Hold that position! Hold it!”
Commanders bellowed trying to stop the retreating soldiers. They even cut down deserting soldiers trying to force them to hold position, but were swept away by the mass of retreating soldiers.
The collapse that began thus soon spread across the entire battle line.
“Retreat!”
“Run away!”
Countless soldiers turned and ran toward the Yalu River while shouting at the top of their lungs.
As this disorderly retreat unfolded, the middle of the Yalu River turned into hell.
A state of congestion occurred as soldiers halted by panokseon attacks became entangled with fleeing soldiers.
And these entangled soldiers became tasty prey for the Type-Eul war wagons.
“You bastards! Think we’d just let you go!”
“Bring all the ammunition we have!”
Joseon soldiers, anger risen to the maximum, madly pulled their triggers at the Liaodong forces tangled in the middle of the river.