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The Marine Nationale will lay down two new classes of warships in 1926, two Duquesene class heavy cruisers, and nine Gallant class destroyers. Their Springstyles follow:

MN Duquesene and MN Gloire will have the range to undertake operations throughout the far-flung French colonial empire:

Duquesene class, French Heavy Cruisers laid down 1926

Displacement:
9,496 t light; 9,997 t standard; 11,773 t normal; 13,193 t full load

Dimensions: Length overall / water x beam x draught
621.43 ft / 613.52 ft x 61.35 ft x 21.98 ft (normal load)
189.41 m / 187.00 m x 18.70 m x 6.70 m

Armament:
9 - 7.87" / 200 mm guns (3x3 guns), 286.60lbs / 130.00kg shells, 1926 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, majority forward, 1 raised mount - superfiring
12 - 3.94" / 100 mm guns (6x2 guns), 35.27lbs / 16.00kg shells, 1926 Model
Dual purpose guns in deck mounts
on side, all amidships
24 - 1.57" / 40.0 mm guns (8x3 guns), 1.98lbs / 0.90kg shells, 1926 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
6 - 0.51" / 13.0 mm guns in single mounts, 0.07lbs / 0.03kg shells, 1926 Model
Machine guns in deck mounts
on side, evenly spread
Weight of broadside 3,051 lbs / 1,384 kg
Shells per gun, main battery: 150

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 3.54" / 90 mm 407.64 ft / 124.25 m 9.84 ft / 3.00 m
Ends: Unarmoured
Main Belt covers 102 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 4.72" / 120 mm 1.97" / 50 mm 3.15" / 80 mm
2nd: 0.98" / 25 mm 0.39" / 10 mm -
3rd: 0.98" / 25 mm - -

- Armour deck: 1.18" / 30 mm, Conning tower: 2.76" / 70 mm

Aviation:
2 Seaplanes, 1 Catapult

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 90,299 shp / 67,363 Kw = 33.00 kts
Range 12,750nm at 15.00 kts (Bunkerage = 3,196 tons)

Complement:
564 - 734

Cost:
£3.493 million / $13.972 million

Distribution of weights at normal displacement:
Armament: 326 tons, 2.8 %
Armour: 1,533 tons, 13.0 %
- Belts: 590 tons, 5.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 344 tons, 2.9 %
- Armour Deck: 569 tons, 4.8 %
- Conning Tower: 31 tons, 0.3 %
Machinery: 2,890 tons, 24.6 %
Hull, fittings & equipment: 4,696 tons, 39.9 %
Fuel, ammunition & stores: 2,277 tons, 19.3 %
Miscellaneous weights: 50 tons, 0.4 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
12,948 lbs / 5,873 Kg = 53.0 x 7.9 " / 200 mm shells or 1.6 torpedoes
Stability (Unstable if below 1.00): 1.09
Metacentric height 2.8 ft / 0.9 m
Roll period: 15.3 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.77
Seaboat quality (Average = 1.00): 1.03

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.498
Length to Beam Ratio: 10.00 : 1
'Natural speed' for length: 28.27 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 68
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 29.53 ft / 9.00 m
- Forecastle (20 %): 22.31 ft / 6.80 m
- Mid (50 %): 22.31 ft / 6.80 m (16.40 ft / 5.00 m aft of break)
- Quarterdeck (15 %): 16.40 ft / 5.00 m
- Stern: 16.40 ft / 5.00 m
- Average freeboard: 19.93 ft / 6.08 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 102.2 %
- Above water (accommodation/working, high = better): 168.2 %
Waterplane Area: 26,031 Square feet or 2,418 Square metres
Displacement factor (Displacement / loading): 118 %
Structure weight / hull surface area: 114 lbs/sq ft or 557 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.96
- Longitudinal: 1.41
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform

Gallant class destroyers:

Gallant class, French Destroyers laid down 1926

Displacement:
1,350 t light; 1,398 t standard; 1,554 t normal; 1,678 t full load

Dimensions: Length overall / water x beam x draught
360.89 ft / 360.89 ft x 32.81 ft x 11.48 ft (normal load)
110.00 m / 110.00 m x 10.00 m x 3.50 m

Armament:
3 - 4.72" / 120 mm guns in single mounts, 61.73lbs / 28.00kg shells, 1926 Model
Dual purpose guns in deck mounts
on centreline ends, majority forward, 1 raised mount
8 - 1.57" / 40.0 mm guns (4x2 guns), 1.95lbs / 0.89kg shells, 1926 Model
Anti-aircraft guns in deck mounts
on side, all amidships
4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1926 Model
Machine guns in deck mounts
on side, evenly spread
Weight of broadside 201 lbs / 91 kg
Shells per gun, main battery: 150
9 - 21.0" / 533 mm above water torpedoes
40 tons depth charges/mines

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.20" / 5 mm -
2nd: 0.98" / 25 mm - -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 35,857 shp / 26,750 Kw = 34.50 kts
Range 6,000nm at 12.00 kts (Bunkerage = 280 tons)

Complement:
123 - 160

Cost:
£0.624 million / $2.498 million

Distribution of weights at normal displacement:
Armament: 22 tons, 1.4 %
Armour: 7 tons, 0.4 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 7 tons, 0.4 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 823 tons, 53.0 %
Hull, fittings & equipment: 458 tons, 29.5 %
Fuel, ammunition & stores: 204 tons, 13.1 %
Miscellaneous weights: 40 tons, 2.6 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
426 lbs / 193 Kg = 8.1 x 4.7 " / 120 mm shells or 0.3 torpedoes
Stability (Unstable if below 1.00): 1.30
Metacentric height 1.5 ft / 0.5 m
Roll period: 11.2 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.20
Seaboat quality (Average = 1.00): 1.04

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.400
Length to Beam Ratio: 11.00 : 1
'Natural speed' for length: 21.80 kts
Power going to wave formation at top speed: 66 %
Trim (Max stability = 0, Max steadiness = 100): 67
Bow angle (Positive = bow angles forward): 0.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 21.33 ft / 6.50 m
- Forecastle (20 %): 15.09 ft / 4.60 m
- Mid (50 %): 13.12 ft / 4.00 m
- Quarterdeck (15 %): 13.12 ft / 4.00 m
- Stern: 13.12 ft / 4.00 m
- Average freeboard: 14.31 ft / 4.36 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 184.7 %
- Above water (accommodation/working, high = better): 75.9 %
Waterplane Area: 7,564 Square feet or 703 Square metres
Displacement factor (Displacement / loading): 62 %
Structure weight / hull surface area: 31 lbs/sq ft or 152 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 1.74
- Overall: 0.57
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is cramped
Ship has slow, easy roll, a good, steady gun platform

Quoted

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern

Didn't we agree that transom sterns were only for ships faster than 34knts?

Invincible BCs have a transom stern as well (historical N3 were planned with one I noticed from a Warships1 LD of that ship andit is of 1921) and I don't remember them being faster than 30 knots or so. Definitely not 34.

http://wesworld.jk-clan.de/thread.php?th…4b139cdd3af84c9
Last ship in the list, and it has a transom stern at 30 knots.

Of course this one as well and is 7 knots slower than the Invincible.

The way I understood it was that transoms could be used on CL-size-and-smaller from '25 onwards, and on larger ships starting ~1930, unless the historical design had a transom (the G3s for instance).

Note that the historical German K-class CLs had a transom stern, so it's not as far-fetched as it seems...

I thought it had to do with getting a more accurate speed for those smaller ships (without them actually having a transom stern). Still I could be wrong.
However, I don't see why a nation would not be able to incorporate a transom stern in the design of a larger vessel when something like the Invincibles are roaming the oceans.
Now if the Invincibles were closely guarded inside a secret antarctic base where no one would see them, then it would be something different.

The problem is that giving ships a transom stern just increases their capability with no obvious side effect. The problems with transom sterns are; bad for minelayers, only work at higher and higher speeds for larger vessels, bad for slow speeds.

HMS Vanguard had a transom stern which resulted in an increase in speed of 3/4 knt. However because she was such a large ship, the transom only really started to be effective at around 25-28knts. At lower speeds than that, it is worse than a normal hullform. As a result, cruising radius is reduced considerably.

Realistically it just means that I can increase speed by about 1-2knts on just about any ship that I have.

Duquesene class, French heavy Cruiser laid down 1926

Displacement:
9,683 t light; 10,154 t standard; 11,917 t normal; 13,328 t full load

Dimensions: Length overall / water x beam x draught
616.80 ft / 616.80 ft x 61.68 ft x 22.38 ft (normal load)
188.00 m / 188.00 m x 18.80 m x 6.82 m

Armament:
9 - 7.87" / 200 mm guns (3x3 guns), 242.51lbs / 110.00kg shells, 1926 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, majority forward, 1 raised mount - superfiring
12 - 3.94" / 100 mm guns (6x2 guns), 35.27lbs / 16.00kg shells, 1926 Model
Dual purpose guns in deck mounts
on side, all amidships
24 - 1.57" / 40.0 mm guns (8x3 guns), 1.95lbs / 0.89kg shells, 1926 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
Weight of broadside 2,653 lbs / 1,203 kg
Shells per gun, main battery: 150

Aviation:
2 Seaplanes, 1 Catapult

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 3.54" / 90 mm 451.61 ft / 137.65 m 9.51 ft / 2.90 m
Ends: Unarmoured
Main Belt covers 113 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 4.72" / 120 mm 1.97" / 50 mm 3.15" / 80 mm
2nd: 0.98" / 25 mm 0.20" / 5 mm -
3rd: 0.98" / 25 mm - -

- Armour deck: 0.98" / 25 mm, Conning tower: 3.94" / 100 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 104,210 shp / 77,740 Kw = 33.00 kts
Range 12,000nm at 15.00 kts (Bunkerage = 3,174 tons)

Complement:
569 - 741

Cost:
£3.731 million / $14.923 million

Distribution of weights at normal displacement:
Armament: 326 tons, 2.7 %
Armour: 1,449 tons, 12.2 %
- Belts: 622 tons, 5.2 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 325 tons, 2.7 %
- Armour Deck: 457 tons, 3.8 %
- Conning Tower: 44 tons, 0.4 %
Machinery: 3,336 tons, 28.0 %
Hull, fittings & equipment: 4,522 tons, 37.9 %
Fuel, ammunition & stores: 2,234 tons, 18.7 %
Miscellaneous weights: 50 tons, 0.4 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
10,217 lbs / 4,634 Kg = 41.9 x 7.9 " / 200 mm shells or 1.4 torpedoes
Stability (Unstable if below 1.00): 1.11
Metacentric height 3.0 ft / 0.9 m
Roll period: 15.0 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.59
Seaboat quality (Average = 1.00): 1.00

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.490
Length to Beam Ratio: 10.00 : 1
'Natural speed' for length: 24.84 kts
Power going to wave formation at top speed: 56 %
Trim (Max stability = 0, Max steadiness = 100): 70
Bow angle (Positive = bow angles forward): 0.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 29.53 ft / 9.00 m
- Forecastle (20 %): 21.00 ft / 6.40 m
- Mid (50 %): 16.73 ft / 5.10 m
- Quarterdeck (15 %): 16.73 ft / 5.10 m
- Stern: 16.40 ft / 5.00 m
- Average freeboard: 18.88 ft / 5.76 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 112.6 %
- Above water (accommodation/working, high = better): 149.0 %
Waterplane Area: 25,120 Square feet or 2,334 Square metres
Displacement factor (Displacement / loading): 111 %
Structure weight / hull surface area: 112 lbs/sq ft or 546 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.97
- Longitudinal: 1.27
- Overall: 1.00
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform

It was just the Transom stern I was objecting to. The design as a whole is fairly good.

My only concerns would be lack of space with 12 secondaries and the catapult as well.