Italian factory correction design mega-thread - Page 2 - Ship Design

Professional

Friday, October 31st 2014, 3:36pm

Quoted from "Brockpaine"

By the way, in the main list of new construction, what happened to the Caeser class ships (the 6x12" vessels)?

Already accounted for in quarterly, so not listed under the revised numbers of ships to be constructed. See the spreadsheets here, specifically the Naval Construction 1931-1935 sheet. The list under Preliminary Planed Composition Q3/45 has only the new construction that has not been accounted for under the quarterly breakdown.

The reason I am going though and redoing/redesigning everything on that list is that I do not yet know how all of it is going to fit together. The designs should not differ much from the existing, I am not out to change the fundamental nature of the Italian Navy and I want it to feel as close as possible to the current incarnation. What is going to differ is when units are laid down. I am going to keep the capital units fixed in place as best I can, which means that there will possibly be lots of adjustments the smaller the ships get. I would like to approach how these changes play out by doing my best to smooth out construction in general which is going to result in changes in laydown years, not to mention those changes that will inevitably be forced by tonnage constraints. I would rather go into that process with an arsenal of Springsharp sims that are vetted by the community that I can then tweak laydown years rather then having to go and do redesigns as I go. Hitting it all at once makes the process simpler for me.

With regards specifically to Portaerei 1936. Part of the reason the design comes out heavier then RA's is the difference in range. 7000nm @25knt is somewhat insane IMO, so I sought to reign that in. With that range, it is a difference in the tens of tons. Looking at the armament again, I can probably slice the number of 100mm to 8 and place the 4 resulting twins in the positions vacated by the midships 152mm guns. Does this look better?

Quoted

Portaerei 1936, Italian Aircraft Carrier laid down 1936

Displacement:
30,000 t light; 30,852 t standard; 35,637 t normal; 39,465 t full load

Dimensions: Length overall / water x beam x draught
856.31 ft / 820.21 ft x 98.43 ft x 29.53 ft (normal load)
261.00 m / 250.00 m x 30.00 m x 9.00 m

Armament:
8 - 5.98" / 152 mm guns in single mounts, 110.23lbs / 50.00kg shells, 1934 Model
Breech loading guns in deck mounts with hoists
on side ends, evenly spread, 4 raised mounts - superfiring
8 - 3.94" / 100 mm guns (4x2 guns), 30.86lbs / 14.00kg shells, 1931 Model
Anti-aircraft guns in deck mounts with hoists
on side, all amidships, all raised mounts - superfiring
16 - 1.46" / 37.0 mm guns (4x4 guns), 1.82lbs / 0.83kg shells, 1932 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
12 - 0.98" / 25.0 mm guns (6x2 guns), 0.55lbs / 0.25kg shells, 1936 Model
Machine guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 1,164 lbs / 528 kg
Shells per gun, main battery: 200

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 5.98" / 152 mm 533.14 ft / 162.50 m 9.84 ft / 3.00 m
Ends: 2.36" / 60 mm 287.04 ft / 87.49 m 9.84 ft / 3.00 m
Main Belt covers 100 % of normal length

- Torpedo Bulkhead:
1.97" / 50 mm 533.14 ft / 162.50 m 32.81 ft / 10.00 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.97" / 50 mm 1.18" / 30 mm 0.79" / 20 mm
2nd: 0.12" / 3 mm 0.79" / 20 mm 0.79" / 20 mm
3rd: 0.39" / 10 mm 0.39" / 10 mm -
4th: 0.39" / 10 mm - -

- Armour deck: 4.33" / 110 mm, Conning tower: 2.76" / 70 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 140,000 shp / 104,440 Kw = 31.58 kts
Range 6,000nm at 25.00 kts
Bunker at max displacement = 8,614 tons

Complement:
1,296 - 1,685

Cost:
£9.063 million / $36.250 million

Distribution of weights at normal displacement:
Armament: 141 tons, 0.4 %
Armour: 7,572 tons, 21.2 %
- Belts: 1,577 tons, 4.4 %
- Torpedo bulkhead: 1,274 tons, 3.6 %
- Armament: 75 tons, 0.2 %
- Armour Deck: 4,581 tons, 12.9 %
- Conning Tower: 64 tons, 0.2 %
Machinery: 3,928 tons, 11.0 %
Hull, fittings & equipment: 9,933 tons, 27.9 %
Fuel, ammunition & stores: 5,637 tons, 15.8 %
Miscellaneous weights: 8,425 tons, 23.6 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
53,224 lbs / 24,142 Kg = 496.7 x 6.0 " / 152 mm shells or 8.9 torpedoes
Stability (Unstable if below 1.00): 1.20
Metacentric height 6.8 ft / 2.1 m
Roll period: 15.8 seconds
Steadiness - As gun platform (Average = 50 %): 61 %
- Recoil effect (Restricted arc if above 1.00): 0.04
Seaboat quality (Average = 1.00): 1.41

Hull form characteristics:
Hull has raised forecastle
and transom stern
Block coefficient: 0.523
Length to Beam Ratio: 8.33 : 1
'Natural speed' for length: 33.07 kts
Power going to wave formation at top speed: 51 %
Trim (Max stability = 0, Max steadiness = 100): 43
Bow angle (Positive = bow angles forward): 30.00 degrees
Stern overhang: 5.31 ft / 1.62 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 53.31 ft / 16.25 m
- Forecastle (20 %): 54.95 ft / 16.75 m (17.22 ft / 5.25 m aft of break)
- Mid (50 %): 17.22 ft / 5.25 m
- Quarterdeck (15 %): 17.22 ft / 5.25 m
- Stern: 17.22 ft / 5.25 m
- Average freeboard: 24.64 ft / 7.51 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 82.3 %
- Above water (accommodation/working, high = better): 144.7 %
Waterplane Area: 57,175 Square feet or 5,312 Square metres
Displacement factor (Displacement / loading): 143 %
Structure weight / hull surface area: 123 lbs/sq ft or 600 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.01
- Longitudinal: 1.00
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Good seaboat, rides out heavy weather easily

2.75m Internal deck hight plus .5m Void

Hanger hight is 11m

Misc Wieght breakdown
--5184t for 72 Aircraft.
--2100t for 50mm flight deck armor.
--500t for crated spares, parts, and workshops
--150t Aircraft Operations Center
--150t Flag Facilities
--100t RADAR
----2xRSC.1 Suface Warning (10t each)
----2xRAC.1 Air Warning (10t each)
----6xRCF.1 General Gunnery Directors (10t each)
--125t Inert gas shielding for AVGAS lines and tanks
--50t Two hydraulic catapults on bow-end of flight deck
--50t Crew Comfort considerations
--16t Reserve

You smug-faced crowds with kindling eye
Who cheer when soldier lads march by,
Sneak home and pray you'll never know
The hell where youth and laughter go.
-Siegfried Sassoon

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Rooijen10

Mr. Valentines Day

Posts: 9,644

22

Friday, October 31st 2014, 3:50pm

Quoted

The design is heavier than Garibaldi by 650 tons. Certainly not saving any tonnage.

Seems to me that it was done to make calculations easier, though I think it should have been brought down to 29,000 tons instead and not up to 30,000 tons.

Quoted

This ship is the same size and only slightly heavier yet carries 12 extra aircraft plus those extra 100mm guns etc.

It is all about calculations. On the original design, it was 6,000 tons for 60 aircraft (at 100 tons each). Now it is 5,184 tons for 72 aircraft (at 72 tons each). On the original design though, it had an armored hangar which is most likely why 100 tons was used.

Quoted

The designs should not differ much from the existing

Based on those two sims and the indication that you want to make calculations easy, it seems to me that the values you gave are the ones you will use, but I can't agree with increasing tonnages of ships to achieve this.

If I read it correctly, you go from

Quoted

Impavido 1933 - 4x2104
Squadrista 1934 - 2x1583
Rosolino Pilo 1936 - 4x2301
Antonio Mosto 1937 - 4x1648
Rimini 1938 - 12x4284
Venezia 1942 - 14x2250
Admiral 1944 - 12x2700

52 destroyers, 142,686 tons

to

Quoted

DD 1933 - 4x2500
DD 1935 - 4x2500
DD 1937 - 4x2500
DD 1939 - 12x2500
DD 1941 - 12x2500
DD 1943 - 12x2500

48 destroyers, 120,000 tons

and from

Quoted

San Calepodio 1932 - 2x6905
Duca degli Abruzzi 1934 - 2x8095
Ischia 1935 - 4x4581
Lombardia 1936 - 4x9910
Genoa 1942 - 4x9750

16 light cruisers, 126964 tons

to

Quoted

CL 1932 - 2x8000
CL 1934 - 2x8000
CL 1936 - 2x8000
CL 1938 - 2x10000
CL 1940 - 2x10000
CL 1942 - 2x10000
CL 1944 - 2x10000

14 light cruisers, 128,000 tons

I see a pair of destroyer designs that are increased more than 50% in displacement. I think that going from 1583 tons to 1600 is acceptable, but 2500 tons? No. Can't really accept that. I could accept going from 4 4581 ton cruisers to 2 4600 ton cruisers, but 2 8000 ton cruisers? No. Can't really accept that. (that's almost a 75% increase)

Also, if you want to save tonnage, going from 126,964 tons in 16 light cruisers to 128,000 tons in 14 light cruisers is not what I would do (especially considering how much needs to be saved). (I know the values are preliminary, but I just thought I should mention it

)

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snip

Professional

Posts: 1,294

23

Friday, October 31st 2014, 4:18pm

Ok, the buy-in is not here. Going to scrap this idea and go back to the drawing board on how to fix the issue.

You smug-faced crowds with kindling eye
Who cheer when soldier lads march by,
Sneak home and pray you'll never know
The hell where youth and laughter go.
-Siegfried Sassoon

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Hood

Ugly Aircraft, Inc

Posts: 8,155

24

Friday, October 31st 2014, 5:49pm

You have a massive task on your hands, I think you need a solution that's easy and quick to implement.

I understand why you want a bundle of designs to work with and moving lay down dates is a very sensible idea.

However, Walter's points are pertinent and echo my own fears. There is a huge gap in funding and cuts or redesigns are necessary but these plans haven't go enough cut, especially if we're talking about 200,000 tons to save. The problem is an infrastructure one, not a design one. By mixing them up you risk all sorts of confusion and don't forget these ships have been around 10-5 years now and doubtless me and Brock and other Med powers have looked at these ships and based our own fleets and plans in response to some of these vessels.

So the answer is either a) cutting hull numbers of existing ships, b) redesigning certain classes that won't fit the available budget to save weight c) a mixture of a & c.
It think whatever the outcome it has to be accepted that a large part of the fleet will cease to exist.

I wonder if there is scope for the mods to do some hand-waving, some kind of gentleman's agreement that some of surplus ships were built by raiding civilian IP/tonnage, perhaps to be paid back later?

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Brockpaine

The Shadow

Posts: 15,109

25

Friday, October 31st 2014, 6:44pm

Quoted from "Hood"

I wonder if there is scope for the mods to do some hand-waving, some kind of gentleman's agreement that some of surplus ships were built by raiding civilian IP/tonnage, perhaps to be paid back later?

It was discussed, but there was insufficient consensus for it.

Quoted from "Rooijen10"

Quoted

This ship is the same size and only slightly heavier yet carries 12 extra aircraft plus those extra 100mm guns etc.

It is all about calculations. On the original design, it was 6,000 tons for 60 aircraft (at 100 tons each). Now it is 5,184 tons for 72 aircraft (at 72 tons each). On the original design though, it had an armored hangar which is most likely why 100 tons was used.

Correct. If you will recall, RA used his own weight calculation for aircraft, rather than using the formula in the Gent's Rules. We had a debate on implementing his formula, but the proposal was voted down since it would have cut the airgroups of all non-Italian carriers by 25-50%. RA continued designing to that calculation, however. Since his formula assigned more weight per aircraft than our rules called for, the mods never saw reason to take action on it while he was here. I.E. "oh well, your loss."

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Rooijen10

Mr. Valentines Day

Posts: 9,644

26

Friday, October 31st 2014, 7:43pm

One thing I missed with Snip's initial post....

Quoted

The new Reginia Elena might get built still. Would depend on what else needs doing. I sort of like having one of (if not the) fastest capital ships in WW.

Depends on how 'capital ships' is defined. I could be wrong, but I think it is probably the fastest ship with a displacement greater than 20,000 tons.

... guess I need to do something about that.

Quoted

So the answer is either a) cutting hull numbers of existing ships, b) redesigning certain classes that won't fit the available budget to save weight c) a mixture of a & c.

"c) a mixture of a & c"? ... uhm... that would be the same as using option "a".

Personally I think "a" to be better as removing a few hulls here and there is going to have a bigger impact on the tonnage total than altering the tonnages of the design, unless the tonnage savings are more extreme like with the Andrea Doria class and the 2 later BB classes.

Looking at the Littorio class, going from 3 40,026 ton battleships to 2 40,000 ton battleship is a good step. That already is 40,078 tons saved, 20% of the mentioned 200,000 tons.

Not sure about the Pisa conversions. If they are partial rebuilds (i.e. 50%) then not doing them saves 29,514 tons. Snips idea to probably replace them with 2-4 smaller CVs is probably not really wise when trying to reduce tonnage useage.

When replacing the current Andrea Doria design with a 30,000 tons one, that would be another 15822 tons saved. If you change the Rimini class DDs from 12 hulls to 8, that would be another 17136 tons.

If you add all those numbers up, that would already get you to 102,550 tons.

I think option "b" does not really matter when it does not fit the available budget. You can shift things around, use less tonnage per quarter and take longer to build the ships in order to make it fit into the quarterly budgets, especially when you combine the shifting of toonages with the removal of a hull here and there in the building program.

Quoted

We had a debate on implementing his formula, but the proposal was voted down since it would have cut the airgroups of all non-Italian carriers by 25-50%. RA continued designing to that calculation, however. Since his formula assigned more weight per aircraft than our rules called for, the mods never saw reason to take action on it while he was here. I.E. "oh well, your loss."

Looking at it, I get the impression that he used armored flightdecks and according the SS notes:

Quoted

British-type carriers with armored flight decks may require a lower airgroup limit, perhaps 2/3 the number generated by this rule.

... so if the Guiseppe Garibaldi is like that, with 6000 tons that is actually only enough for 51 planes if you use 2/3 of the number generated by the SS rules.

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Brockpaine

The Shadow

Posts: 15,109

27

Friday, October 31st 2014, 8:21pm

Quoted from "Rooijen10"

Quoted

We had a debate on implementing his formula, but the proposal was voted down since it would have cut the airgroups of all non-Italian carriers by 25-50%. RA continued designing to that calculation, however. Since his formula assigned more weight per aircraft than our rules called for, the mods never saw reason to take action on it while he was here. I.E. "oh well, your loss."

Looking at it, I get the impression that he used armored flightdecks and according the SS notes:

Quoted

British-type carriers with armored flight decks may require a lower airgroup limit, perhaps 2/3 the number generated by this rule.

... so if the Guiseppe Garibaldi is like that, with 6000 tons that is actually only enough for 51 planes if you use 2/3 of the number generated by the SS rules.

Right, although that doesn't match up with the number of aircraft RA said the ships operated. It might perhaps be a case of wanting to have your cake and eat it too. :rolleyes:

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snip

Professional

Posts: 1,294

28

Friday, October 31st 2014, 8:28pm

Stuff like this is also part of why I want to do resims. Gets rid of any rule issues with RA's designs.

You smug-faced crowds with kindling eye
Who cheer when soldier lads march by,
Sneak home and pray you'll never know
The hell where youth and laughter go.
-Siegfried Sassoon

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Hood

Ugly Aircraft, Inc

Posts: 8,155

29

Friday, October 31st 2014, 9:10pm

Sorry I meant, C) mixture of A and B.

True, there are question marks over RAs carrier sims, so I've no objection to anything that is suspect being resimmed, but that should probably be resims as corrections rather than keel-up redesigns.

I think Walter had some good ideas for tonnage savings there.
Another 6,500 tons could be saved by making the Tripolitanias repeat/improved Littorios (at the expense of 6 guns though). The last Pisa conversions were done after quite a gap so they could be removed, even so I've always had doubts over their utility.

Another thought, did any of the excess tonnage take Italy over the Cleito Treaty limits? This would have to be another consideration during the early period of the new reports.

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BruceDuncan

Ex chaos ordo

Posts: 12,916

30

Friday, October 31st 2014, 11:28pm

Depending how the proposed Italian building schedule progresses, I have a concern that may go away. However, in looking at the plan previously posted I note that the Italian stockpile at the end of 4Q30 exceeds 100,000 tons.

This violates our current stockpile rule (where a nation's total stockpile may not exceed one years production) and it certainly violates the stockpile rule in play at the time of the original sim reports. In the circumstances, I feel that a rolling stockpile up to our current limit (which for Italy, with 18+2 factories in 1930 would be 80,000 tons) would be acceptable, but I would not want to see a stockpile grow beyond it. Doing so would make the final version of the Italian Navy far younger that it would otherwise be.

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snip

Professional

Posts: 1,294

31

Friday, October 31st 2014, 11:32pm

Quoted from "BruceDuncan"

Depending how the proposed Italian building schedule progresses, I have a concern that may go away. However, in looking at the plan previously posted I note that the Italian stockpile at the end of 4Q30 exceeds 100,000 tons.

This violates our current stockpile rule (where a nation's total stockpile may not exceed one years production) and it certainly violates the stockpile rule in play at the time of the original sim reports. In the circumstances, I feel that a rolling stockpile up to our current limit (which for Italy, with 18+2 factories in 1930 would be 80,000 tons) would be acceptable, but I would not want to see a stockpile grow beyond it. Doing so would make the final version of the Italian Navy far younger that it would otherwise be.

As things take greater shape I would flesh out that period more.

You smug-faced crowds with kindling eye
Who cheer when soldier lads march by,
Sneak home and pray you'll never know
The hell where youth and laughter go.
-Siegfried Sassoon

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BruceDuncan

Ex chaos ordo

Posts: 12,916

32

Friday, October 31st 2014, 11:36pm

Quoted from "snip"

Quoted from "BruceDuncan"

Depending how the proposed Italian building schedule progresses, I have a concern that may go away. However, in looking at the plan previously posted I note that the Italian stockpile at the end of 4Q30 exceeds 100,000 tons.

This violates our current stockpile rule (where a nation's total stockpile may not exceed one years production) and it certainly violates the stockpile rule in play at the time of the original sim reports. In the circumstances, I feel that a rolling stockpile up to our current limit (which for Italy, with 18+2 factories in 1930 would be 80,000 tons) would be acceptable, but I would not want to see a stockpile grow beyond it. Doing so would make the final version of the Italian Navy far younger that it would otherwise be.

As things take greater shape I would flesh out that period more.

I realize that not everything may be accounted for in the current iteration of your spreadsheet, but looking at the out years the values for the stockpile - as they stand at the moment - grow alarmingly - hence my concern.

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Rooijen10

Mr. Valentines Day

Posts: 9,644

33

Saturday, November 1st 2014, 12:22am

Quoted

Another thought, did any of the excess tonnage take Italy over the Cleito Treaty limits? This would have to be another consideration during the early period of the new reports.

From what I can remember, there was something that Italy violated, but could not remember what so I looked around.

Unfortunately I can't find a Cleito Treaty on the board (only empty posts with no text). I have one but that is a CT discussion version so I can't tell if it is the same as the final one.

Based on that copy I have, I noticed that in most cases Italy was within the limits, but Italy was allowed to have a maximum of 70000 tons carrier tonnage. With the rebuild Francesco Morosini (1x27986), two Aquila (2x22813) and two converted Condottieris (2x6101) the total is 85814 tons. With the 5% error we were allowed, 95% would give 81524 tons in the early 1930s.

Unfortunately, Italy's violations of the CT was one of the reasons Japan left so I can't agree to changes which would result in Italy no longer violating the CT.

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BruceDuncan

Ex chaos ordo

Posts: 12,916

34

Saturday, November 1st 2014, 12:50am

Walter, you mean this isn't the Cleito Treaty?

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The Rock Doctor

Old-School Heel

Posts: 5,310

35

Saturday, November 1st 2014, 12:50am

My recollection is that SATSUMA disbelieved a class of cruisers qualified as the Class A ships they were claimed to be. I don't recall Italy being over it specific tonnage allocations per se.

I'm pretty certain Snip's already said those cruisers are going to happen.

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Rooijen10

Mr. Valentines Day

Posts: 9,644

36

Saturday, November 1st 2014, 1:53am

Quoted

Walter, you mean this isn't the Cleito Treaty?

With search, I actually ended up with this one...
http://wesworld.jk-clan.de/index.php?pag…+treaty#post536

Noticed now that it is in the archives. I guess I should have looked further than that.

On the other hand, from what I can see this is not the original one. I get the impression that this is the post Copenhagen conference version (although it should not vary too much with the original when it comes to tonnages).

*goes off to check the tonnages*

Quoted

My recollection is that SATSUMA disbelieved a class of cruisers qualified as the Class A ships they were claimed to be. I don't recall Italy being over it specific tonnage allocations per se.

You could be right with that, Rocky. Still I do know there was something with Italy's ships that was not 100% right.

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Rooijen10

Mr. Valentines Day

Posts: 9,644

37

Saturday, November 1st 2014, 2:23am

Okay. According to the Cleito Treaty link, Italy is allowed a maximum of 70,000 tons of Carrier tonnage so it does not change the fact that Italy exceeded the carrier tonnage by more than 10,000 tons. In RA's mind, a pair of cranes on the flightdecks of the Alberico da Barbiano and Bartolomeo Colloeoni was enough to get around the "It must be so constructed that aircraft can be launched therefrom and landed thereon" bit and thus those two ships should not be counted towards the carrier tonnage.

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snip

Professional

Posts: 1,294

38

Thursday, November 6th 2014, 5:25pm

Walter and Hood. I really want to address your concerns here to move forward with this. So far I think the sticking points are below. If I missed anything, please let me know.

--Why not just handwave the issue out of existence or handle it IC?
----We discussed this when the problem was just isolated to 1931, but when the 1929 issues came to light as well it was felt by both myself and others that the problem had outgrown the scope of what a handwaved or IC solution could address.

--Why modify designs at all?
----I feel there are a lot of Italian designs that do not make sense under the reduced factory numbers. I know Italian practice in the past has not exactly been the paragon of sanity, but I feel strongly about some of the designs *cough*Rimini*cough* not making any practical sense to construct under a reduced factory cap.

--Why resim most of the designs that would be kept anyway?
----I want to make sure that any silly business left within the sims gets squashed. Also having correct sims allows me to shuffle around construction dates and plan refits more efficiently.

--What about other navies responding to the original designs?
----That is why the sims presented so far do not have much difference from the classes that were built by RA around the same time. I want to keep the same feel of the Italian Navy, especially with regards to capital units.

--Why does the preliminary plan have such different tonnage numbers for smaller ships?
----I wanted to give myself lots of flexibility when reworking smaller ships. I felt the best way to do that was to over-budget for them.

--Why do some ship classes have a budget of higher then there current counterparts?
----Again on the over-budgeting. Additionally, playing with the fuel loads (for achieving a standardized cruise speed and toning down radical numbers) will be altering the displacement. See Portaerei 1936 vs GG.

--Why does the plan seem so loaded into 1930+?
----I just realized I forgot to copy the header of that table. The plan is currently geared around what the fleet would look like in Q3/45. I figured that it would be the best place to start. My apologies for missing the header.

Any other questions/comments/concerns?

You smug-faced crowds with kindling eye
Who cheer when soldier lads march by,
Sneak home and pray you'll never know
The hell where youth and laughter go.
-Siegfried Sassoon

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snip

Professional

Posts: 1,294

39

Friday, November 7th 2014, 12:04am

I went in and shaved 1000t off of the Portaerei 1936 at the expense of some flightdeck armor. Note the hangers are not armored, just the flightdeck.

Quoted

Portaerei 1936, Italian Aircraft Carrier laid down 1936

Displacement:
29,000 t light; 29,829 t standard; 34,498 t normal; 38,233 t full load

Dimensions: Length overall / water x beam x draught
856.31 ft / 820.21 ft x 98.43 ft x 29.53 ft (normal load)
261.00 m / 250.00 m x 30.00 m x 9.00 m

Armament:
8 - 5.98" / 152 mm guns in single mounts, 110.23lbs / 50.00kg shells, 1934 Model
Breech loading guns in deck mounts with hoists
on side ends, evenly spread, 4 raised mounts - superfiring
8 - 3.94" / 100 mm guns (4x2 guns), 30.86lbs / 14.00kg shells, 1931 Model
Anti-aircraft guns in deck mounts with hoists
on side, all amidships, all raised mounts - superfiring
16 - 1.46" / 37.0 mm guns (4x4 guns), 1.82lbs / 0.83kg shells, 1932 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
12 - 0.98" / 25.0 mm guns (6x2 guns), 0.55lbs / 0.25kg shells, 1936 Model
Machine guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 1,164 lbs / 528 kg
Shells per gun, main battery: 200

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 5.98" / 152 mm 533.14 ft / 162.50 m 9.84 ft / 3.00 m
Ends: 2.36" / 60 mm 287.04 ft / 87.49 m 9.84 ft / 3.00 m
Main Belt covers 100 % of normal length

- Torpedo Bulkhead:
1.97" / 50 mm 533.14 ft / 162.50 m 32.81 ft / 10.00 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.97" / 50 mm 1.18" / 30 mm 0.79" / 20 mm
2nd: 0.12" / 3 mm 0.79" / 20 mm 0.79" / 20 mm
3rd: 0.39" / 10 mm 0.39" / 10 mm -
4th: 0.39" / 10 mm - -

- Armour deck: 4.33" / 110 mm, Conning tower: 2.76" / 70 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 140,000 shp / 104,440 Kw = 31.81 kts
Range 6,000nm at 25.00 kts
Bunker at max displacement = 8,404 tons

Complement:
1,265 - 1,645

Cost:
£8.878 million / $35.512 million

Distribution of weights at normal displacement:
Armament: 141 tons, 0.4 %
Armour: 7,497 tons, 21.7 %
- Belts: 1,576 tons, 4.6 %
- Torpedo bulkhead: 1,274 tons, 3.7 %
- Armament: 75 tons, 0.2 %
- Armour Deck: 4,509 tons, 13.1 %
- Conning Tower: 63 tons, 0.2 %
Machinery: 3,928 tons, 11.4 %
Hull, fittings & equipment: 9,733 tons, 28.2 %
Fuel, ammunition & stores: 5,498 tons, 15.9 %
Miscellaneous weights: 7,700 tons, 22.3 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
52,195 lbs / 23,675 Kg = 487.1 x 6.0 " / 152 mm shells or 8.8 torpedoes
Stability (Unstable if below 1.00): 1.21
Metacentric height 7.0 ft / 2.1 m
Roll period: 15.7 seconds
Steadiness - As gun platform (Average = 50 %): 61 %
- Recoil effect (Restricted arc if above 1.00): 0.04
Seaboat quality (Average = 1.00): 1.43

Hull form characteristics:
Hull has raised forecastle
and transom stern
Block coefficient: 0.507
Length to Beam Ratio: 8.33 : 1
'Natural speed' for length: 33.14 kts
Power going to wave formation at top speed: 50 %
Trim (Max stability = 0, Max steadiness = 100): 43
Bow angle (Positive = bow angles forward): 30.00 degrees
Stern overhang: 5.31 ft / 1.62 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 53.31 ft / 16.25 m
- Forecastle (20 %): 54.95 ft / 16.75 m (17.22 ft / 5.25 m aft of break)
- Mid (50 %): 17.22 ft / 5.25 m
- Quarterdeck (15 %): 17.22 ft / 5.25 m
- Stern: 17.22 ft / 5.25 m
- Average freeboard: 24.64 ft / 7.51 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 82.1 %
- Above water (accommodation/working, high = better): 146.0 %
Waterplane Area: 56,278 Square feet or 5,228 Square metres
Displacement factor (Displacement / loading): 143 %
Structure weight / hull surface area: 122 lbs/sq ft or 595 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.00
- Longitudinal: 1.01
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Good seaboat, rides out heavy weather easily

2.75m Internal deck hight plus .5m Void

Hanger height is 11m

Misc Wieght breakdown
--5184t for 72 Aircraft.
--1350t for 30mm flightdeck armor
--500t for crated spares, parts, and workshops
--150t Aircraft Operations Center
--150t Flag Facilities
--100t RADAR
----2xRSC.1 Surface Warning (10t each)
----2xRAC.1 Air Warning (10t each)
----6xRCF.1 General Gunnery Directors (10t each)
--125t Inert gas shielding for AVGAS lines and tanks
--50t Two hydraulic catapults on bow-end of flight deck
--50t Crew Comfort considerations
--16t Reserve

You smug-faced crowds with kindling eye
Who cheer when soldier lads march by,
Sneak home and pray you'll never know
The hell where youth and laughter go.
-Siegfried Sassoon

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Hood

Ugly Aircraft, Inc

Posts: 8,155

40

Friday, November 7th 2014, 9:30am

Thanks Snip, that rationale makes sense to me.
This is just such a huge project that its best to make sure its good from the start. I think resimming makes sense in regards to the problems. It's hard to have meaningful comments when you've only just started, hopefully as you post more designs and flesh out the spreadsheets more it'll make more sense as we go along.

It was just the balance seemed out with much larger ships replacing smaller ones, if you can keep a decent mix then it should be ok. Certainly some of the odder designs should probably go or be recast.

Portaerei 1936 looks ok to me. Shaving the hangar armour is probably a wise move, as is removing that odd stern catapult. Both are luxury items the new Italian Navy can ill afford.

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