Saint Louis class

[Ariecho]

http://www.secondegu...pr/st_louis.gif

 

Little is available about that class, as it was never built.

 

This class was meant to replace the aging Duguay-Trouin class that appeared in 1923.  Approved in April 1940, their entry into service was scheduled for 1943.  Experts believe that these modern ships would have been very close to the US Baltimore class.

 

Displacement: 15,950 tons standard -19,422 tons fully loaded

Dimensions 202 m (length), 20 m (width), 5,80 m draft.

Propulsion 4 turbines Parsons, 130,000 hp.

Speed: 34 kts

Protection: 210 mm

Armament: 9 203 mm (3x3), 8 100 mm (4x2), 8 37 mm (4x2), 16 13.2 mm AA MGs, 3 planes

Crew: 760

 

 

http://i61.servimg.c...83/saint-10.jpg

 

[EDIT] Edited to convert tonnes into tons.

[JeeWeeJ]

Awesome ship Ari! But i believe you missed a little bit af French in the specs as it says "de tirant d'eau".. :Smile_smile:

[Ariecho]

JeeWeeJ, on 01 October 2012 - 02:36 PM, said:

Awesome ship Ari! But i believe you missed a little bit af French in the specs as it says "de tirant d'eau".. :Smile_smile:

You're correct!  At least, that tells you that I get my information from the right sources :Smile_teethhappy:

[JeeWeeJ]

Ariecho, on 01 October 2012 - 02:41 PM, said:

You're correct!  At least, that tells you that I get my information from the right sources :Smile_teethhappy:

Lol, as if anyone on these forums doubted your sources on French ships.. :Smile_glasses:

[Capcon]

A belt of 210mm is substantial.

[ReiAyanami]

Ariecho, great post and great ships, +1.

BTW  it says 4,470 tonnes standard which is too light and can't be true if they are17,620 tonnes fully loaded, probably the number is 14,470t

 

Also 9x8 inch guns,a 210mm belt and, 34knots at a max displacement of 17000t doesn't seem realistic considering the rest of ww2 heavy cruisers which couldn't achieve all that with larger displacement. I suspect that one of those three stats would have been nerfed by the builders to make the other two possible, or the ships would actually be many thousand tons heavier.

[Capcon]

ReiAyanami, on 01 October 2012 - 03:10 PM, said:

Ariecho, great post and great ships, +1.
BTW  it says 4,470 tonnes standard which is too light and can't be true if they are17,620 tonnes fully loaded

Also 9x8 inch guns,a 210mm belt and, 34knots at a max displacement of 17000t doesn't seem realistic considering the rest of ww2 heavy cruisers which couldn't achieve all that with larger displacement. I suspect that one of those three stats would have been nerfed by the builders to make the other two possible, or the ships would actually be many thousand tons heavier.

Not that I disagree that this is a lot in a package this size, It has more horsepower than a Baltimore, more armor but  . . .
I'm assuming the operational range would be short by US standards so it would save on weight of fuel
I would expect it to save on weight of hull, typical for French versus US construction at the time.
Six 5"/38 gunhouses ammo and crew do add up to quite a bit more weight than four twin 4" AA guns.

Interesting ship.

[Ariecho]

ReiAyanami, on 01 October 2012 - 03:10 PM, said:

Ariecho, great post and great ships, +1.
BTW  it says 4,470 tonnes standard which is too light and can't be true if they are17,620 tonnes fully loaded, probably the number is 14,470t

Also 9x8 inch guns,a 210mm belt and, 34knots at a max displacement of 17000t doesn't seem realistic considering the rest of ww2 heavy cruisers which couldn't achieve all that with larger displacement. I suspect that one of those three stats would have been nerfed by the builders to make the other two possible, or the ships would actually be many thousand tons heavier.

Correct, it is 14,470 tonnes

[Ariecho]

Capcon, on 01 October 2012 - 03:25 PM, said:

Not that I disagree that this is a lot in a package this size, It has more horsepower than a Baltimore, more armor but  . . .
I'm assuming the operational range would be short by US standards so it would save on weight of fuel
I would expect it to save on weight of hull, typical for French versus US construction at the time.
Six 5"/38 gunhouses ammo and crew do add up to quite a bit more weight than four twin 4" AA guns.

Interesting ship.

I also suspect that the belt didn't cover front and aft part of the ship, as was typical of French designs.  As a matter of fact, if you look at the C5 top picture, it says "longueur protegee" (protected length) and shows the area that would have received a protected belt.

[ReiAyanami]

Capcon, on 01 October 2012 - 03:25 PM, said:

Not that I disagree that this is a lot in a package this size, It has more horsepower than a Baltimore, more armor but  . . .
I'm assuming the operational range would be short by US standards so it would save on weight of fuel
I would expect it to save on weight of hull, typical for French versus US construction at the time.
Six 5"/38 gunhouses ammo and crew do add up to quite a bit more weight than four twin 4" AA guns.

Interesting ship.

I quote from wiki

Quote

Standard displacement
The standard displacement, also known as Washington disp, is a term defined in the Washington Naval Treaty. It is defined as the displacement of the ship complete, fully manned, engined, and equipped ready for sea, including all armament and ammunition, equipment, outfit, provisions and fresh water for crew, miscellaneous stores, and implements of every description that are intended to be carried in war, but without fuel or reserve boiler feed water on board

So 14,470 for Saint Louis vs 14,733 for Baltimore, so I'm still unconvinced. I don't doubt the French engineering, but this is too op, as fast as a destroyer and immune to heavy cruiser guns, hmmm

[Ariecho]

ReiAyanami, on 01 October 2012 - 04:21 PM, said:

I quote from wiki


So 14,470 for Saint Louis vs 14,733 for Baltimore, so I'm still unconvinced. I don't doubt the French engineering, but this is too op, as fast as a destroyer and immune to heavy cruiser guns, hmmm

So, what is the difference then between standard displacement and fully loaded displacement?

[JeeWeeJ]

Maybe the amount of fuel has something to do with it? As i believe French ships usually carried a lot less fuel than their American counterparts did.

[Capcon]

Ariecho, on 01 October 2012 - 05:37 PM, said:

So, what is the difference then between standard displacement and fully loaded displacement?

Full load should be all fuel, reserve feed water (fresh water for boilers) but not overload, all ammo, full crew, and supplies for X days, with X being set by the navy in question. Basically all gassed up and ready to fight.

Fuel and feed water for a battle ship would be thousands of tons.

Destroyers carried something like 500-600 tons of fuel on an 1,800 ton standard displacement.

[Ariecho]

ReiAyanami, on 01 October 2012 - 04:21 PM, said:

I quote from wiki


So 14,470 for Saint Louis vs 14,733 for Baltimore, so I'm still unconvinced. I don't doubt the French engineering, but this is too op, as fast as a destroyer and immune to heavy cruiser guns, hmmm

Could it just be that we're talking tonnes versus tons?  So, 14,470 tonnes would be 15,950 tons?

[Elouda]

JeeWeeJ, on 01 October 2012 - 05:41 PM, said:

Maybe the amount of fuel has something to do with it? As i believe French ships usually carried a lot less fuel than their American counterparts did.

Standard displacement is the ship with everything minus fuel and reserve boiler feed water on board.

I agree those numbers look a little too optimistic for 14,470 tons, even if the belt is short (which most cruiser belts were anyway). Then again, it would be far from the only optimistic design study in the interwar period.

[Ariecho]

Elouda, on 01 October 2012 - 05:54 PM, said:

Standard displacement is the ship with everything minus fuel and reserve boiler feed water on board.

I agree those numbers look a little too optimistic for 14,470 tons, even if the belt is short (which most cruiser belts were anyway). Then again, it would be far from the only optimistic design study in the interwar period.

Again, it's 14,470 tonnes, not 14,470 tons!!!  14,470 tonnes is equal to 15,950 tons

[Elouda]

Ariecho, on 01 October 2012 - 05:56 PM, said:

Again, it's 14,470 tonnes, not 14,470 tons!!!  14,470 tonnes is equal to 15,950 tons

Actually that would be 14,700 tons, since the ton in use here (and most naval literature) is the long ton. As the variance is ~1.6%, it makes little difference to the result in most ballpark estimates.

[Ariecho]

Elouda, on 01 October 2012 - 06:00 PM, said:

Actually that would be 14,700 tons, since the ton in use here (and most naval literature) is the long ton. As the variance is ~1.6%, it makes little difference to the result in most ballpark estimates.

All French documents I found about the Saint Louis refer to metric tonnes.

[Elouda]

Ariecho, on 01 October 2012 - 06:03 PM, said:

All French documents refer to metric tonnes.

Yes, as do German and Japanese post-metric conversion. Most US and UK documents use long tons, as do the Washington and London Naval Treaty numbers unless otherwise stated.

1 tonne = 1000kg
1 long ton = 2240lbs = 1016kg

Again, unless were doing something very precise like actual physical models, that ~1.6% difference makes no difference to the matter at hand.

[Ariecho]

Elouda, on 01 October 2012 - 06:05 PM, said:

Yes, as do German and Japanese post-metric conversion. Most US and UK documents use long tons, as do the Washington and London Naval Treaty numbers unless otherwise stated.

1 tonne = 1000kg
1 long ton = 2240lbs = 1016kg

Again, unless were doing something very precise like actual physical models, that ~1.6% difference makes no difference to the matter at hand.

But are we talking long ton or short ton (and I'll admit I don't have a clue)?  All converters I found were that 1 tonne = 1.10 ton = 907kg

[Elouda]

Ariecho, on 01 October 2012 - 06:10 PM, said:

But are we talking long ton or short ton (and I'll admit I don't have a clue)?  All converters I found were that 1 tonne = 1.10 ton = 907kg

The short ton is the more commonly used one in the US as far as I know, except when dealing with naval matters, where the standard is the long ton, often abbreviated to just ton. Practically all US ship displacements (and certainly everything post-WNT) is given in long tons.

[Ariecho]

Elouda, on 01 October 2012 - 06:20 PM, said:

The short ton is the more commonly used one in the US as far as I know, except when dealing with naval matters, where the standard is the long ton, often abbreviated to just ton.

I stand corrected.

[Elouda]

Ariecho, on 01 October 2012 - 06:20 PM, said:

I stand corrected.

No worries, it was a good catch, and worth explaining. Im prone to just sticking 'ton' in there even for metric designs simply out of habit, and partially out of laziness (ton is easier to type than long ton or tonne :tongue:).

I still think the designs look a little optimistic on that displacement, but as said it would be far from the only one paper study to do that.

If one accepted the belt being rather limited (ie Magazine and Machinery only, and limited in height) and horizontal (deck) protection being practically nothing, then I could see it work on ~15,000tons and a 'stressed' hull. I'd guess 16,000tons to do it 'properly' though.

[MasterWolf]

ReiAyanami, on 01 October 2012 - 04:21 PM, said:

I quote from wiki


So 14,470 for Saint Louis vs 14,733 for Baltimore, so I'm still unconvinced. I don't doubt the French engineering, but this is too op, as fast as a destroyer and immune to heavy cruiser guns, hmmm

Difference is Short Ranged med based cruiser with limited operational theater (typical french inter war thinking) vrs Long Range extended operation theater (US interwar thinking) - the fule bunkerage alone would accont for much of the weight differential

[Elouda]

MasterWolf, on 01 October 2012 - 06:32 PM, said:

Difference is Short Ranged med based cruiser with limited operational theater (typical french inter war thinking) vrs Long Range extended operation theater (US interwar thinking) - the fule bunkerage alone would accont for much of the weight differential

Except these are standard tonnages, which do not include fuel.

There will be some difference due to differences in living quarters and amenities, but not enough for that difference by a long shot.