"The destroyer we are going to build has an initial standard displacement set at 1,400 tons," Shire said. "The full load displacement is around 2,000 tons, which can be adjusted as needed."

Tijani took notes while saying, "Why don't we build a cruiser with a standard displacement of around 4,000 tons directly? The larger the displacement, the stronger the firepower, Vice Admiral, it is even more cost-effective."

As the "prince" of the Brest Shipyard, Tijani knew that tonnage and cost were not directly proportional, and often, the larger the tonnage, the lower the average cost.

"Speed, General." Shire's answer was simple: "Under the same technical and industrial level, the larger the tonnage, the slower the speed."

"Speed?" Tijani put down his pen and looked at Shire with confusion. "If we already have airplanes, I mean, airplanes carrying torpedoes, why do we need to emphasize the speed of destroyers?"

Shire countered, "Even on land, with aircraft cover, do tanks not need speed?"

Tijani hesitated for a moment, reluctantly saying, "But this seems different from tanks. Tanks can hide with quantity and various methods, but there are few warships on the sea, facing aircraft, they can't evade."

Shire continued to counter, "What if the enemy uses torpedo boats or destroyers, those small but high-speed ships, to attack? Do we also choose to use aircraft carrying torpedoes to sink them?"

Tijani was speechless.

Sinking destroyers might be feasible, but torpedo boats are fast and hard to hit with torpedoes, even if they are hit, it wouldn't be worthwhile.

Shire continued to analyze:

"Any combat should be systematic, General."

"In previous naval battles, the system included torpedo boats, destroyers, cruisers, and battleships, which cooperated with each other to form powerful combat capabilities."

"Our new type of destroyer is not just a destroyer, but aims to break this old system to form a new combat system."

Tijani thought for a while, his face uncertain: "You mean, a new system formed by the cooperation between destroyers and aircraft?"

"Yes," Shire replied. "Both must cooperate, not constrain each other, requiring both to have self-preservation capabilities so they won't be each other's weak spots to be exploited by the enemy."

Tijani understood: "Aircraft have self-preservation ability, they can always fly out of enemy fire range and join the battle at the right time, but warships can't."

Shire nodded: "The self-preservation capability of warships is also speed."

"You're right," Tijani generously admitted his mistake. "So, the tonnage of the warship is determined by the current technical level and the speed of enemy warships. The enemy's destroyers have a speed of around 33 knots, ours must have at least this speed as well."

With a speed of 33 knots plus aircraft reconnaissance, battleships with speeds around 19 knots can be completely ignored, as they simply can't catch up with destroyers.

It can also largely ignore cruisers with speeds around 29 knots.

Thus, on the vast ocean, destroyers will only face enemy destroyers, or when entering enemy's coastal regions, they might face torpedo boats.

Understanding this makes the subsequent decisions easier.

"Since our main opponent is enemy destroyers, the ship's guns can't be reduced; preliminary designs include four 130MM primary guns."

This is determined by the enemy destroyers' firepower in this era and the lack of dive bombers development; the new destroyers cannot have only a few guns like modern ones.

"Additionally, add two triple torpedo launchers."

Most destroyer torpedo tubes at this time are dual launchers. Shire's use of triple launchers aims to increase the number of torpedoes launched simultaneously, enhancing the impact of new torpedoes.

"Two deep water bomb tracks with 22 bombs."

Shire deliberately weakened the destroyer's anti-submarine requirements.

The reason is the primary opponent of the French Fleet is the Royal Navy, not the German Navy.

On the other hand, Shire's new destroyer is designed for maneuver warfare at sea, utilizing the high-speed of 33 knots rather than for escort purposes.

Submarines during World War I sailed at around ten knots on the surface and only eight to ten knots underwater, posing no real threat to this type of warship.

Tijani noted all this down, although he had some questions regarding anti-submarine warfare, he didn't ask further.

After considering for a moment, he raised a question: "I heard our new warship is mainly for air defense, yet so far, I haven't seen any air defense firepower."

Shire took out a blueprint from a drawer and handed it to Tijani: "The air defense firepower will use this machine cannon, with a 20MM caliber."

"20MM caliber?" Tijani asked with suspicion, "The Germans' Becker cannon?"

But after taking Shire's blueprint, he found the machine cannon on the blueprint was slightly different from the Becker cannon, with roughly the same structure but a longer, thinner barrel.

(The prototype for the Oerlikon cannon, invented by the Germans' Becker, hence called Becker cannon. Initially used by the Germans on aircraft, it was soon shot down and captured by the Allies. Its feature is the unique advanced recoil system, reducing recoil, thus widely used in air defense cannons and aircraft cannons)

(Mass-used Oerlikon machine cannon on warships)

Shire only showed the blueprint to Tijani briefly and then took it back, instead handing over a data file.

"I will be responsible for the production of the machine cannon," Shire said, "You only need to know these data and reserve cannon positions on the broadside."

This machine cannon used for air defense can't be said to be secret, but Shire's improved version of the Oerlikon 20MM cannon was indeed a secret. It had higher rate of fire and muzzle velocity than the original Becker, with significantly improved performance, and couldn't be easily disclosed.

Shire planned for this cannon to be manufactured in the artillery factory in Davaz Town.

Regarding equipment that could counterbalance one's own designs, Shire believed caution was necessary.

Like this Oerlikon cannon, during World War II, nearly 30% of aircraft were shot down by it.

Besides, it could also be used as an aircraft cannon.

Putting it on aircraft to shoot at tanks could easily penetrate the tank's top armor, turning into an effective ground attack aircraft.

Tijani understood the implications and nodded: "Understood, Vice Admiral. If I were you, I would also do everything to keep it secret. After all, you're inventing equipment to counter your own."

Then he laughed: "This must be exhausting, I mean, becoming your own opponent!"

Shire sighed inwardly.

Inventing equipment to a certain extent inevitably leads to such a situation.

Now he could only hope the enemy wouldn't quickly replicate and "feedback" it back to him!