Late Ming sea owl

Chapter 245 Disadvantages of the Manila Galleon

Hearing the decision announced by Lin Hai, all the craftsmen were very excited. Even Old Song, who had been the most ardent opponent of building a cruise ship, was eager to try it.

Those who can become master craftsmen are not stupid. Everyone understands that once someone's design is selected, he or she will basically be the chief designer of the ship.

As the chief designer of the company's first independently built cruise ship, there is no need to explain the significance of this. This has a fatal attraction to all master craftsmen, even Lao Pan, the director of the Ship Bureau, is no exception.

After much hesitation, Lao Pan decided to give up this opportunity: "Boss, I will not participate in this matter. I believe that you masters will come up with the best design."

The ship designs of this era were certainly not as complicated as those of later generations, but they were not random either. Although there were no precise drawings, there were still rough patterns, and the key dimensions had to follow general rules based on experience.

In the later era of sailing battleships, warships were mainly designed around artillery arrangements, and the input conditions given by the navy to the designers mainly included: the number of guns on each gun deck, the spacing between guns, and the height from the gun ports of the lower gun deck to the waterline.

Based on these constraints, the length of the gun deck can be calculated, and then the beam, depth, draft and other parameters can be designed. The length-to-width ratio of the gun deck is between 3 and 4, generally around 3.5. The depth generally does not exceed 75% of the beam, and the draft generally does not exceed 75% of the depth, and most of them are around 50%.

These are all empirical values, and actual adjustments will be made based on the situation. The so-called molded depth refers to the distance from the midpoint of the beam of the first continuous deck above the waterline to the upper edge of the keel. For a sailing battleship, this deck is the lower gun deck.

The draft also limits the design of the underwater line shape. Generally speaking, the shape of the rib with the largest width in the middle of the hull must be determined first, which determines the line shape of the cross section. Then the longitudinal shape is designed based on experience, and the shape of the remaining ribs can be calculated based on this. At this point, the main dimensions of the hull structure are basically designed.

However, warships at that time were not designed around artillery. People often considered the ship first and then the artillery. Therefore, Lin Hai only gave a tonnage constraint, and the rest was left to the designers to decide based on their own experience.

As for the configuration of the artillery, it can only be determined according to the situation of the ship at that time. In a nutshell, the ship determines the artillery, not the artillery determines the ship. This is the case for warships of this era, and this is also the biggest difference between galleons and battleships.

Lin Hai did not have the blueprints of future battleships, so he did not dare to easily change the design habits of that era. What the Construction Department feared most was administrative intervention in technology and laymen guiding experts.

After all, Gu Erye's Vasa is a living example. The result of this guy's blind command was that this 69-meter-long giant ship only sailed 1300 meters after being launched and capsized when a gust of wind blew.

However, after weighing the pros and cons, Lin Hai decided to put forward his own request: "Everyone, I want to say one more thing. When designing a cruiser, you must give priority to firepower. This is the most critical indicator for a warship."

There are many performance indicators for warships. Firepower, speed, seaworthiness, and maneuverability are all important, and it is even difficult to say which one is more important. Many of these indicators are mutually constrained, and the design work is mainly about making trade-offs and trying to achieve the overall optimality.

But if we have to choose the most important one among all the performance indicators, it should still be firepower for a cruiser.

The reason is simple. Firepower can destroy all performance indicators of the enemy ship: So what if you have a high speed? I will destroy a few of your sails and then come out for a walk? So what if you have good maneuverability? I will destroy your rudder, bowsprit, or mizzenmast and then we will fight again?

After all, a sailboat is a slow and clumsy machine - while a cannon is as powerful as thunder! After hearing Lin Hai's words, Pan Xuezhong thought for a while: "In other words, try to design the warship to be longer."

The guns of a battleship are mainly arranged on the sides. The larger the length-to-width ratio, the easier it is to arrange more guns. This is an obvious principle.

For example, the Dingyuan, the flagship of Huiyou Company, has a displacement of 1000 tons. The Spaniards only installed 38 guns on it. After the company installed more guns, it now has 44 guns, including 2 bow guns and 2 stern guns.

In comparison, the famous Dutch battleship VIII Provinces, which was built more than 1200 years later, had a displacement of 80 tons but was equipped with 54 guns, and that was only the broadside guns. Of course, this is definitely unfair, as VIII Provinces had two gun decks, but even if one was removed, it still had guns, which was a clear advantage.

What was the problem? The lower gun deck of Qisheng was 46.14 meters long and 12.17 meters wide amidships, with a length-to-width ratio of 3.8, which was greater than the length-to-width ratio of the entire Dingyuan (excluding the bowsprit)!

The Manila Galleon was really fat! This was reflected in the cross-sectional line shape, and also in its small aspect ratio.

This may be because the Spanish were the first to invent the galleon, and the galleon was derived from the caravel. So compared to the British and Dutch, who had the latecomer advantage, the Spanish galleon retained more of the caravel's legacy - the latter's length-to-width ratio is generally around 3, which is the length-to-width ratio of the entire ship excluding the bowsprit.

Another example of the Carrack legacy is that Spanish ships tend to have taller poops, which has the following disadvantages:

First, a superstructure that is too high is prone to capsizing, firstly because the center of gravity is raised, and secondly because the side area exposed to wind is increased;
Secondly, the heavy poop brings a deeper stern draft, which not only reduces the seaworthiness but also reduces the speed, which in turn reduces the rudder efficiency.
Finally, the towering stern tower is like a huge air tail, which together with the deeper tail draft improves the static stability of the heading.

Does this last point sound like an advantage? Maybe for merchant ships that sail mainly with the wind, but not for warships.

How often does a warship sail downwind? I'm afraid it's more likely to sail with a sidewind, a crosswind, or even close to the wind. At this time, the effect of static stability is negative and not conducive to maintaining the course.

Static stability refers to the tendency of the posture to return to the same direction as the fluid under the action of the fluid. Strong static stability will lead to reduced maneuverability. For example, in the aerospace field of later generations, launch vehicles that do not pursue maneuverability tend to be designed with strong static stability, while air-to-air missiles that particularly emphasize lateral maneuverability often adopt a statically unstable overall layout.

"Pan, you are so good at talking! Let me ask you, if the battleship is designed to be longer, not to mention the larger turning radius, how can the longitudinal strength be guaranteed?"

At this time, Master Song, who couldn't hold back, jumped out again. He didn't dare to criticize Lin Hai in person, so he caught Pan Xuezhong and criticized him, his saliva almost sprayed on the boy's face.

However, even Master Song himself did not realize that since joining the Ship Bureau of Huiyou Company, he has used many new words that he has never said before, such as turning radius and longitudinal strength.

(End of this chapter)