So… let’s talk about the Marco Polo. Being revealed as the tier IX Premium Italian battleship, Marco Polo is inspired by the design UP.41. from Ansaldo.
For the description of the design, credits to Phoenix_jz, one of our great naval history enthusiasts on Discord. I sadly lack knowledge on Italian designs but he, on the other hand, really knows a lot about them.
Now I say that Marco Polo is inspired by the UP.41 because there are a few differences. Firstly, the layout for the secondary battery is different. On the Marco Polo, the 90 mm secondaries are close to each other around the superstructure while on the UP.41, they were meant to be split into groups of 3 turrets.
There is also the issue of the engine power. Where the UP.41 was planned to have 180 000 HP, Marco Polo only has 140 000 HP.
From what I understood, there are also issues with the armor scheme that shouldn’t look like that/doesn’t fit in terms of thickness.
For the classic reminder, this is a ship in testing, anything can change so don’t look at her like she would already be released.
To compensate for her low HP pool, the Marco Polo presents some really good armor protection which, coupled with her good handling and good firing angles will allow her to mitigate the damage against AP or simply shatter the HE of enemy cruisers.
The bow section
The bow is mostly covered by the usual 32 mm plating. except for a 130 mm extended belt.
The extended belt ends with an internal 70 mm bulkhead to help dealing with shells that would possibly penetrate the bow.
Behind that bulkhead, there are 2 armored decks above each other. These are 100 mm thick and combined with the rest, will effectively protect the ship from getting citadelled through the bow.
For the protection of the middle section, the upper casemate is 150 mm thick. Then, there is a 300 mm bulkhead that includes the upper part of the citadel athwartship and finally, a lower, underwater casemate that is 38 mm thick.
The middle section
When it comes to the middle section, the deck is 55 mm thick granting her an immunity against the HE of most cruisers outside of the British 234 mm, Graf Spee, Ägir and Siegfried (without counting IFHE).
For the sides, the upper belt is 70 mm thick except for a tiny little 60 mm strip before the main belt. The said main belt is 350 mm thick and finally, the underwater torpedo bulge is 38 mm.
The internal protection of the Marco Polo is simply crazy. Firstly, behind the main belt, she has an additional 40 mm thick armored belt. After that, she has… somewhat of a mix of turtleback and sloped citadel deck at 62° to 70° which is 35 mm thick.
Finally, the lower part of the citadel is 60 mm thick.
So yes, 2 belts to go through and then either the sloped deck or the turtleback. This ship will be very hard to citadel for sure…
…Unless it’s against carriers with AP bombs in which case, it looks fairly easy.
Below the 55 mm weather deck, there is a first 25 mm deck and then the main armor deck which is 90 mm thick on the sides and 100 mm thick for the citadel deck. In total, it doesn’t seem to be much but the different layers are potentially far enough from each other for the bombs to explode before reaching the citadel.
For the external protection of the stern, it is the classic 32 mm plating.
Inside the stern, there is an internal armored deck which is 130 mm thick for the sloped sides and 100 mm thick in the middle.
For the protection of the middle section, the upper casemate is 150 mm thick then you have the 300 mm thick bulkhead and the lower casemate with 38 mm of armor.
When it comes to the superstructure, it’s is fairly small and narrow. It is for the most part protected by 19 mm of armor except for the conning towers with 250 mm to 370 mm of armor.
There are also the barbettes of the 90 mm secondaries standing high with 80 mm of armor.
The turrets of the Marco Polo are fairly well protected. The face is 410 mm thick with a 20° slope, the sides are 150 mm thick, the back is 400 mm thick and for the roof, it’s 220 mm thick at the front and 190 mm thick and the rear.
For the barbette, the top is 100 mm thick, the upper part is 350 mm thick and the lower part is 200 mm thick.
The ship has one major downside in the form of the second-lowest HP pool of all non-stock tier IX battleships. Except that… she frankly looks pretty damn strong. The guns will be fairly nasty with the SAP boosting 102 mm of penetration, being able to overmatch anything under 30 mm of armor AND the high alpha. The AP is also nothing to laugh at since it’s one of the best performing 406 mm AP shells after the Izumo, Champagne and Slava.
The combination of strong armor, speed, agility and concealment will also be a good compensation for the lack of HP.