In order to protect the construction of the pontoon bridge from the enemy's destruction, it is necessary to provide appropriate protection while building the pontoon bridge, so that the pontoon bridge is foolproof.

For this reason, Cao Liang had a bold idea, which was to build a crossbow flying stone ship.

This is a brand new design concept, combining the crossbow cart with the chain catapult and the warship. At the bow, a fixed crossbow is set up, and in the middle of the ship, a serial catapult cart invented by Ma Jun is arranged.

The serial catapult car is based on ordinary catapult car, and adopts a rotor design, hangs the stone bullets on the rotor and launches them in turn, greatly increasing the launch frequency.

However, the chain catapult car that Cao Liang now uses is not the original version of Ma Jun, but has been improved by his design. When Ma Jun designed the chain catapult car, he did not yet have the concept of equipped catapult car. Even the chain catapult car is a human pulling type, which requires a lot of pulling hands to operate, and may be implemented on flat ground, but if this catapult car is really moved to the warship, there is no room for operation.

Therefore, Cao Liang upgraded the human-pulled catapult to a counterweight type, which greatly reduced the number of people operating the catapult, making it possible to get on the boat.

Cao Liang did not use ordinary catapults, but used an improved version of the serial catapults. The main reason is that the launch frequency of ordinary catapults is low, and the launch frequency of serial catapults is four to five times that of ordinary catapults. If dozens of warships attack at the same time, they can form an effective strike force.

Although the stone bombs used in the chain of stone casters were smaller and the damage was much less powerful, the target they needed to attack this time was not a solid city wall, and these small stone bombs were just right to use.

This is a very bold idea and creativity. Before this, no one would have linked a ship with a catapult carriage and a crossbow carriage, but Cao Liang could break the old rules, innovate, and creatively designed this brand new warship.

When Cao Liang handed the drawings to Huan Fan, Huan Fan looked numb and was not surprised at all. After all, there were too many incredible things that Cao Liang created. It seemed that in this world, there were only things Cao Liang could not imagine, and nothing he could not do. Cao Liang's many inventions and creations were already far ahead of this era. One by one, his own innovations were already amazing. Huan Fan would naturally not be too surprised when he moved the crossbow and the chain catapult to the ship. He just needed to assign craftsmen to strictly follow the drawings provided by Cao Liang.

This kind of ship is slightly larger than an ordinary ferry, but it is not difficult to build. After all, the skills of shipbuilders in the north are much worse than those in the Wu Kingdom. The craftsmen in the Wu Kingdom can not only build warships like Mengchong, but also build tower ships up to five or six floors. There are no big rivers and rivers in the north, and craftsmen cannot build large ships.

However, Cao Liang only needs to be able to install a series of catapults and two crossbows. Obviously, an ordinary warship is more than enough, and there is no need for too much ship.

Before Cao Liang's northern expedition, each sample ship was quickly built. At the bow, two crossbows were placed side by side. This crossbow car has the characteristics of long-range and fast firing speed. It has miraculous effects in suppressing enemy archers. In the center of the hull, a chain catapult car was placed. At this time, in order to pursue stability, the wheels of the catapult car had been removed, and the base of the catapult car was completely fixed on the deck of the ship. No matter how big the vibration was, it would not cause displacement.

In order to avoid being learned by Sima's army's detailed work, this model ship was built completely under extremely confidentiality. Only a few people in the Bingzhou army knew about it. After completion, Cao Liang conducted a test launch on it, but he was quite satisfied with the results. After some minor adjustments, he will eventually enter large-scale mass production.

At that time, when the Huns Liu Yuan invaded Bingzhou, Cao Liang gave up his plan to cross the river and resolutely returned to Bingzhou to resolve the Hu people's rebellion first, and assigned the task of building a crossbow flying stone ship to Huan Fan.

Cao Liang originally planned to build at least fifty crossbow flying stone ships, which was just a plan proposed when time was tight at that time. The crossing plan was shelved for more than a year. Huan Fan had the time to calmly build crossbow flying stone ships. With sufficient raw materials, Huan Fan finally built 100 such ships, which was doubled compared to Cao Liang's original plan.

In addition, Huan Fan also reserved tens of thousands of special stone bullets and tens of thousands of crossbow arrows. These crossbow flying stone ships and other ships were moored at the ferry on the north bank of the Yellow River, and were covered with thick blue curtains. Not only did the Sima army not know what these ships were, but even most of the Bingzhou army were kept in the dark and thought they were ordinary ferries.

After Cao Liang arrived in Liyang, he immediately went to the Yellow River to inspect the water conditions. As the ice surface of the Yellow River melted, the water of the Yellow River also became smoother and the water level was greatly reduced. This was the best time to cross the river.

Baima Ferry is an extremely important ferry crossing in the lower reaches of the Yellow River. The river surface is wide and the water flows smoothly. It became Cao Liang's first choice for crossing the river.

Of course, Sima Shi also fought against the tit-for-tat, personally stationed the Baima, gathered heavy troops at the Baima Ferry, and prepared to fight Cao Liang to the death.

This battle is also very important for Sima Shi. After the defeat of Jizhou, the Sima army suffered heavy losses and had lost the ability to compete with the Bingzhou army head-on. Only by relying on the natural danger of the Yellow River can we barely support the current situation. If the Yellow River defense line is lost, the entire Qingyan, Xuyu and the four prefectures south of the Yellow River will directly fall under the iron hoof of the Bingzhou army, and even Luoyang may be difficult to preserve, so the importance of this Yellow River defense line is self-evident.

The Yellow River defense line that Sima devoted all his efforts to build, and it was naturally not easy to conquer it. However, Cao Liang had his own killer weapon, which was these crossbow flying stone ships. When hundreds of ships of the Bingzhou army were launched together and the crossbow arrows flew stones like locusts, even the strongest defense line of Sima would be useless.

On the night of arriving in Liyang, Cao Liang convened a meeting of all the generals above the camp and fully deployed the plan for crossing the river. He decided to launch a comprehensive general attack on the sixth day of the second month, seven days later.

Cao Liang asked that the troops of each battalion must complete the preparations before crossing the river before the fifth day of the second month, and the construction of the floating bridge will also be carried out in advance to ensure that the completion will be completed smoothly on the sixth day of the second month, and the general attack time will not be delayed for a moment.
Chapter completed!