Shipbucket

I've always been a bit unimpressed by battlecruisers historically. As a whole, they were not a very successful type of ship in my opinion. That is not to say they never had combat success, but for ships that attempted to be powerful enough to fight in the battle line they wound up getting their teeth kicked in by real battleships whenever they encountered them. Even Germany's newest, most advanced battlecruisers of World War 1, the Derrflingers, stood no chance coming under fire from the Royal Navy's Queen Elizabeth class. So I think it was a mistake to try and squeeze enough firepower out of them to make them functional line of battle warships.

The idea of taking the armored cruiser concept and applying the dreadnought principle of a unified main battery however is an entirely different story. At the Falklands, Dogger Bank, and even at Jutland battlecruisers proved they could kick the living daylights out of other fast ships. To build large high speed ships wasn't the mistake. So with all this in mind I took a stab at creating a contemporary to Vonn der Tann and Invicible, but one that focuses it's strengths on being suited to fighting cruisers while forgoing any notion of battle line combat. As with most of my designs, she's not tied to any real countries or people.



And as always, a Springsharp File to outline her capabilities,

Surigao, Regia Nautica Battlecruiser laid down 1907 (Engine 1909)

Displacement:
16,374 t light; 17,104 t standard; 18,958 t normal; 20,441 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(553.89 ft / 552.00 ft) x 81.00 ft x (28.00 / 29.69 ft)
(168.83 m / 168.25 m) x 24.69 m x (8.53 / 9.05 m)

Armament:
8 - 10.00" / 254 mm 50.0 cal guns - 608.00lbs / 275.78kg shells, 100 per gun
Breech loading guns in turret on barbette mounts, 1908 Model
4 x Twin mounts on centreline, evenly spread
2 raised mounts
Aft Main mounts separated by engine room
12 - 4.00" / 102 mm 43.0 cal guns - 31.26lbs / 14.18kg shells, 300 per gun
Quick firing guns in casemate mounts, 1905 Model
12 x Single mounts on sides amidships
6 - 2.25" / 57.2 mm 50.0 cal guns - 6.03lbs / 2.73kg shells, 500 per gun
Anti-air guns in deck mounts, 1910 Model
6 x Single mounts on sides amidships
6 raised mounts
Weight of broadside 5,275 lbs / 2,393 kg
8 - 18.0" / 457 mm, 22.00 ft / 6.71 m torpedoes - 1.024 t each, 8.192 t total
In 4 sets of deck mounted side rotating tubes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 8.00" / 203 mm 332.00 ft / 101.19 m 16.00 ft / 4.88 m
Ends: 3.00" / 76 mm 190.00 ft / 57.91 m 16.00 ft / 4.88 m
30.00 ft / 9.14 m Unarmoured ends
Upper: 4.00" / 102 mm 332.00 ft / 101.19 m 8.00 ft / 2.44 m
Main Belt covers 93 % of normal length

- Hull Bulges:
0.00" / 0 mm 0.00 ft / 0.00 m 0.00 ft / 0.00 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 9.20" / 234 mm 3.00" / 76 mm 9.20" / 234 mm
2nd: 5.50" / 140 mm - -

- Armoured deck - single deck: 2.25" / 57 mm For and Aft decks

- Conning towers: Forward 9.20" / 234 mm, Aft 0.00" / 0 mm

Machinery:
Coal fired boilers, steam turbines,
Direct drive, 4 shafts, 80,391 shp / 59,972 Kw = 28.00 kts
Range 10,000nm at 10.00 kts
Bunker at max displacement = 3,336 tons (100% coal)

Complement:
807 - 1,050

Cost:
£1.595 million / $6.381 million

Distribution of weights at normal displacement:
Armament: 1,126 tons, 5.9 %
- Guns: 1,117 tons, 5.9 %
- Torpedoes: 8 tons, 0.0 %
Armour: 4,900 tons, 25.8 %
- Belts: 2,662 tons, 14.0 %
- Armament: 1,109 tons, 5.9 %
- Armour Deck: 988 tons, 5.2 %
- Conning Tower: 141 tons, 0.7 %
Machinery: 4,020 tons, 21.2 %
Hull, fittings & equipment: 6,069 tons, 32.0 %
Fuel, ammunition & stores: 2,584 tons, 13.6 %
Miscellaneous weights: 260 tons, 1.4 %
- Hull below water: 45 tons
- Hull void weights: 10 tons
- Hull above water: 45 tons
- On freeboard deck: 100 tons
- Above deck: 60 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
21,806 lbs / 9,891 Kg = 43.6 x 10.0 " / 254 mm shells or 2.3 torpedoes
Stability (Unstable if below 1.00): 1.15
Metacentric height 4.8 ft / 1.4 m
Roll period: 15.6 seconds
Steadiness - As gun platform (Average = 50 %): 56 %
- Recoil effect (Restricted arc if above 1.00): 0.51
Seaboat quality (Average = 1.00): 1.03

Hull form characteristics:
Hull has rise forward of midbreak,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.530 / 0.539
Length to Beam Ratio: 6.81 : 1
'Natural speed' for length: 23.49 kts
Power going to wave formation at top speed: 58 %
Trim (Max stability = 0, Max steadiness = 100): 55
Bow angle (Positive = bow angles forward): 4.00 degrees
Stern overhang: -4.00 ft / -1.22 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 27.00 ft / 8.23 m, 26.00 ft / 7.92 m
- Forward deck: 40.00 %, 26.00 ft / 7.92 m, 25.00 ft / 7.62 m
- Aft deck: 20.00 %, 12.00 ft / 3.66 m, 12.00 ft / 3.66 m
- Quarter deck: 20.00 %, 12.00 ft / 3.66 m, 14.00 ft / 4.27 m
- Average freeboard: 20.48 ft / 6.24 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 91.9 %
- Above water (accommodation/working, high = better): 149.7 %
Waterplane Area: 30,626 Square feet or 2,845 Square metres
Displacement factor (Displacement / loading): 108 %
Structure weight / hull surface area: 144 lbs/sq ft or 704 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.94
- Longitudinal: 1.86
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent

To summarize, I ended up on a hull roughly the size of Invincible and VdT. The armor scheme is comparably thick to the best contemporary armored cruisers, and the 8x 10 inch gun broadsidew uses a custom approach to the 10 inch caliber I devised. It lobs a much heavier 600~ pound projectile and uses a longer barrel to accelerate it to a moderate but respectable velocity. It's supposed to rely more on throw weight than striking velocity.

The propulsion situation is interesting, because the indicated speed is 28 knots, 2 knots faster than Invincible. But the indicated horsepower says she makes over 80,000 SHP, which is nearly twice that of Invincible's design base horsepower. And slightly higher than the 10,000 tons heavier HMS Lion. Who also makes 28 knots. Either Springsharp is giving me an incredibly oversized engine for making 28 knots or the real speed of the ship is something in excess of 30 knots in all likelylyhood. Either way, the design does place a high emphasis on speed to chase down and kill armored cruisers that are weaker than it, and the extremely high speed gives it a comfortable margin of safety against even the fastest WW1 battleships.

Oh yeah and it has rotating torpedo tubes. Because it's already an oversized cruiser, so might as well make it able to launch torpedo attacks with the rest of the cruisers.

Thoughts and criticism are welcome, please and thank you

That is Jabbas Invincible hull, so the first thing to do is to get your crediting correct, His name goes first, yours second.

The drawing itself is no more than ok. The guns are too long for the size of the turrets. BC's of that era have very tall topmasts because of the weak radio signals they had at the time. The higher the mast and wireless wires the further they could send and receive, very necessary when hunting armoured cruisers in the Pacific or Atlantic oceans.

Propulsion at 28 knots is about right for the hull shape. Invincible was 567x79, to increase the hull to 81 feet will only slow you down, using 10" guns you could reduce the hull size to 75 feet. Turbine propulsion of that era were large and clumsy. It will be another 25 years before you could put that propulsion system into that sized hull.

Fixed the crediting issue, and I'm really sorry about it. It's an older drawing I dusted off, back from before I knew proper crediting. And yeah, my skills are unremarkable aesthetically. I need to improve but I'm not entirely sure how.

The hull has been extended by 60 feet and trimmed at the beam by 7 feet (for a total beam of 76 feet). Also frees up space for another 4 inch secondary gun per side. Be afraid destroyers, be very afraid.

Also added taller radio masts to crows nest to increase signal range without adding undue top weight as per your tip about radio signals. Hopefully this would make a noticable improvement.

I still have a hard time believing that a ship that ostensibly generates as much power as HMS Lion, on a 10,000 ton lighter hull, can't go any faster. Springsharp is giving me 76,000 horsepower indicated after the beam reduction. Can you explain a bit of the numbers and engineering behind this a bit in depth? I'm always looking to further my understanding of naval engineering if you are willing to elaborate.

Those are the 9.2" Mk XII Originally made as 9.45" Elswick Pattern 'E' made for the two coastal defence ship of the Bjorgvin class that was bought by the Brits from Norway and named Gorgon class. The gun itself was lifted from a railroad artillery. They was given the length on those barrels to increase the velocity and range on those guns. When they was made, they had the second longest firing range, for Naval guns, only a 18" monitor gun had longer range.

Note these turrets had only 1 gun in them, but in his drawing they are supposed to have two guns. With that he should have increased the turret ring, and increased the turret counter weight. But I would just take HMS Agincourt 12" turret and replace the 12" guns with the 9.2" (10") guns




All ship hull have an Naturall top-speed, if you want more speed than the hull can give, you need to multiply the size of the engine. The faster a ship goes thus more water it push and drag with it, these more water it push, more power you need.

All these number in the text below are not accurate numbers, they are numbers taken out of the air to present an example and should be treated like that
Many ship of the era have around 50% of the engine power going to move the water, the other 50% goes to move the weight of the ship. That will say that with a 1000 ton ship you are moving 1000 ton of water, at top speed. But when you want more speed, the ratio start to change. for example 2-3 knots more: you use around 56% of the engine power to move the water around the ship, that will say a 1000 ton ship, moving 2-3 knots faster, you move 1560 ton of water. 5 knots more: 68-70% of engine power goes to the water: 1000 ton ship moves 1700 ton of water. 8 knots more: 80% engine power goes to water: 1000 ton ship, 1800 ton of water.

so a ship at 20000 tons going 4 knots faster the the Natural top speed of the hull itself are pushing 33600 ton of water... one of the reason is due to that many ship with these hull design have a tendency to go deeper in the water at higher speed.

For example: When the a largest cruise ship of the time, Royal Caribbean's Allure of the Seas. delivered from a shipyard in Finland had to go under Denmark's Storebaelt Bridge. They had to go at max speed, because when they did, the ship hull dig it self deeper in the water. just to get under the bridge...

So what I'm getting from Huehue's explanation is that once you exceed natural speed any increase in engine size gives diminishing returns. So the only way to get a significant increase in speed is to improve hull form.

Also, the barbette one my drawing is bigger than the one I pulled off the part sheet. 37 pixels for the single mount, 43 for my twin type. Perhaps further expansion is required to make it more realistically sized?

Your bow is also out of place. Capitol ships of the time had a ram bow, even the battlecruisers. Some of the British ones had basicly a "stubby" ram bow, not as prominent as on the battleships.

I'm struggling to see what this would give you over the Lion Class that comes along only a couple of years later. The Lion can keep up with it, hits harder and from further away. I will grant you that it's a marked improvement over the 1st gen battlecruisers and a lovely looking ship.

There are many things, that give advantage over Lion class
same speed yes, but not so maneuverable as an smaller and lighter ship. easier to avoid incoming shoots
3.5" bigger guns, more weight, but have shorter range. Lion class 13.5" guns had a range of only 22+km, while the guns Surigao is based on have a max range of 36 km (the second longest shooting gun, in that era!). It can also fire faster than the Lion.


So overall if we look on weight of shell that can be delivered during a time period, the difference isn't that big. but the biggest advantage Surigao class have over Lion class is that it have longer ranging guns.




Lion class Battlecruiser
build 1910-1912
armed with a 13.5" guns that have an maximum range of 22 km (as a ship mounted gun, coastal artillery have longe range)

Surigao class (the drawing)
build 1909
Armed with 10" guns, The gun is based on the 9.2" Mark XII guns, that have an maximum range of 28km (Standard) and 36km (supercharged)

Trying to hit anything at that range in WWI (or worse in 1907) is simply imposable so the extra is totally wasted apart from secondary missions like shore support.
You have guns firing 275Kg shells v 574.5 kg that's not a small difference (even worse, 172.4 kg if you go with the super long range Norwegian shell!),
The firing rates on navweps are effectively the same (2 v 1.5-2 and the twin 10"will be probably be slower than the real single).

She is massively smaller and earlier than Lion so you should match her v Indefatigable class but she still will lose v a 385.6 kg.

Anyway she does look nice my questions about the design would be.
Why the 1907/8/9 date change hull/engines/guns ?

- 6 - 2.25" / 57.2 mm 50.0 cal guns - 6.03lbs / 2.73kg shells, 500 per gun
Anti-air guns in deck mounts, 1910 Model,
who are you shooting down in 1909?

- single deck: 2.25", bit early for single deck isn't it?

- 4 sets of deck mounted side rotating tubes, why not under water?

- No TDS ?

-Range 10,000nm at 10.00 kts do you need ?

- 'Natural speed' for length: 23.49 kts, can you make this better ?

The problem is, between 1908 and 1920 you go from the 18,000 ton Invincible through to the 42,000 ton Hood. Virtually when one class is completed, the enemies answer outclasses it and requires ever larger sized ships with bigger guns and more speed.

So you can only compare apples with apples, Scootia23's BC of 1909 is equivalent to Invincible (1908) and Von Der Tann (1910) and outclasses all previous armoured cruisers up to and including the German Blucher. The ship is faster than Invincible and Von der Tann, fires further than both. In terms of shells Scootia23's 10" is a development of the earlier long range 9.4" sleeved to 9.2" 'Norwegian' gun. Firing a 600lb shell compared to the 660lb German and 850lb RN shell. The armour schemes, the Surigao has 8" belt, Invincible 6", Von der Tann 9.8". Von Der Tann is the best of the 3 ships. Completed in 1910 it was Germanys answer to Invincible, but where the Germans built one, the three Invincibles' would have overwhelmed the Von der Tann. The Surigao should probably beat the Invincible but it is like the USA-USSR, Mutually Assured Destruction, one lucky hit from either could spell doom.