WesWorld

Here is the proposed rebuild for the ex-Brazilian Margay Class. Internal sources are yet to confirm how many ships will be rebuilt to this standard.

Project 451 (ex-Margay Class), Brazil Destroyer (Argentine Refit 1942) laid down 1932 (Engine 1942)

Displacement:
2,039 t light; 2,145 t standard; 2,602 t normal; 2,967 t full load

Dimensions: Length overall / water x beam x draught
401.26 ft / 390.00 ft x 40.00 ft x 13.00 ft (normal load)
122.30 m / 118.87 m x 12.19 m x 3.96 m

Armament:
6 - 5.12" / 130 mm guns (3x2 guns), 70.55lbs / 32.00kg shells, 1937 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, majority forward, 1 raised mount - superfiring
14 - 1.46" / 37.0 mm guns (7x2 guns), 1.55lbs / 0.70kg shells, 1937 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
4 - 0.79" / 20.0 mm guns in single mounts, 0.24lbs / 0.11kg shells, 1937 Model
Anti-aircraft guns in deck mounts
on side, all amidships, all raised mounts - superfiring
Weight of broadside 446 lbs / 202 kg
Shells per gun, main battery: 210
4 - 21.0" / 533.4 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 1.00" / 25 mm 390.00 ft / 118.87 m 8.00 ft / 2.44 m
Ends: Unarmoured
Main Belt covers 154 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.97" / 50 mm 0.98" / 25 mm 2.00" / 51 mm
2nd: 0.59" / 15 mm - -
3rd: 0.39" / 10 mm - -

- Armour deck: 0.25" / 6 mm, Conning tower: 1.00" / 25 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 3 shafts, 40,000 shp / 29,840 Kw = 31.39 kts
Range 15,000nm at 12.00 kts
Bunker at max displacement = 822 tons

Complement:
181 - 236

Cost:
£1.173 million / $4.694 million

Distribution of weights at normal displacement:
Armament: 53 tons, 2.0 %
Armour: 197 tons, 7.6 %
- Belts: 115 tons, 4.4 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 31 tons, 1.2 %
- Armour Deck: 46 tons, 1.8 %
- Conning Tower: 4 tons, 0.2 %
Machinery: 1,015 tons, 39.0 %
Hull, fittings & equipment: 724 tons, 27.8 %
Fuel, ammunition & stores: 562 tons, 21.6 %
Miscellaneous weights: 50 tons, 1.9 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,081 lbs / 490 Kg = 16.1 x 5.1 " / 130 mm shells or 0.5 torpedoes
Stability (Unstable if below 1.00): 1.30
Metacentric height 2.0 ft / 0.6 m
Roll period: 11.8 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.49
Seaboat quality (Average = 1.00): 1.18

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.449
Length to Beam Ratio: 9.75 : 1
'Natural speed' for length: 19.75 kts
Power going to wave formation at top speed: 63 %
Trim (Max stability = 0, Max steadiness = 100): 59
Bow angle (Positive = bow angles forward): 25.00 degrees
Stern overhang: 1.00 ft / 0.30 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 22.00 ft / 6.71 m
- Forecastle (20 %): 16.00 ft / 4.88 m
- Mid (50 %): 16.00 ft / 4.88 m
- Quarterdeck (15 %): 16.00 ft / 4.88 m
- Stern: 16.00 ft / 4.88 m
- Average freeboard: 16.48 ft / 5.02 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 144.8 %
- Above water (accommodation/working, high = better): 137.8 %
Waterplane Area: 9,943 Square feet or 924 Square metres
Displacement factor (Displacement / loading): 94 %
Structure weight / hull surface area: 39 lbs/sq ft or 191 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 1.56
- Overall: 0.56
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

Refit Changes
120mm mounts replaced by 130mm Mk III DP mounts
Addition of two twin 37mm AA mouns in place of upper torpedo tube mount
New main director
Addition of
New boilers and tubines
Refurbishment of internal fittings

If you're going to go to the trouble for a 25% job, I'd ditch the belt and see if you can get a little more speed on her.

I would have dropped the belt but I felt that the belt might be integral to the hull (given the smaller dimensions of the hull) so might be tricker to remove.

Thought I'd share this new offical picture of the Belgrano Class as built.

Sweet!

Nice drawing; good work to you both.

Awesome drawing !!!!!

Here is a plan to rebuild one of the Margay Class destroyers into a school ship.
Thoughts?

Project 451C (ex-Margay Class), Brazil School Ship (Argentine Refit 1942) laid down 1932 (Engine 1942)

Displacement:
2,119 t light; 2,204 t standard; 2,602 t normal; 2,919 t full load

Dimensions: Length overall / water x beam x draught
401.26 ft / 390.00 ft x 40.00 ft x 13.00 ft (normal load)
122.30 m / 118.87 m x 12.19 m x 3.96 m

Armament:
2 - 5.12" / 130 mm guns (1x2 guns), 70.55lbs / 32.00kg shells, 1937 Model
Dual purpose guns in a deck mount with hoist
on centreline forward
2 - 4.53" / 115 mm guns (1x2 guns), 55.12lbs / 25.00kg shells, 1937 Model
Dual purpose guns in a deck mount with hoist
on centreline forward, all raised guns - superfiring
8 - 1.46" / 37.0 mm guns (4x2 guns), 1.55lbs / 0.70kg shells, 1937 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
4 - 0.79" / 20.0 mm guns in single mounts, 0.24lbs / 0.11kg shells, 1937 Model
Anti-aircraft guns in deck mounts
on side, all amidships, all raised mounts - superfiring
Weight of broadside 265 lbs / 120 kg
Shells per gun, main battery: 200
4 - 21.0" / 533.4 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 1.00" / 25 mm 390.00 ft / 118.87 m 8.00 ft / 2.44 m
Ends: Unarmoured
Main Belt covers 154 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.97" / 50 mm 0.98" / 25 mm 2.00" / 51 mm
2nd: 1.97" / 50 mm 0.98" / 25 mm 2.00" / 51 mm
3rd: 0.39" / 10 mm - -
4th: 0.39" / 10 mm - -

- Armour deck: 0.25" / 6 mm

Machinery:
Oil fired boilers, steam turbines plus diesel motors,
Geared drive, 3 shafts, 40,000 shp / 29,840 Kw = 31.39 kts
Range 13,000nm at 12.00 kts
Bunker at max displacement = 715 tons

Complement:
181 - 236

Cost:
£1.106 million / $4.424 million

Distribution of weights at normal displacement:
Armament: 30 tons, 1.2 %
Armour: 180 tons, 6.9 %
- Belts: 115 tons, 4.4 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 19 tons, 0.7 %
- Armour Deck: 46 tons, 1.8 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 1,028 tons, 39.5 %
Hull, fittings & equipment: 700 tons, 26.9 %
Fuel, ammunition & stores: 483 tons, 18.5 %
Miscellaneous weights: 180 tons, 6.9 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,069 lbs / 485 Kg = 15.9 x 5.1 " / 130 mm shells or 0.5 torpedoes
Stability (Unstable if below 1.00): 1.26
Metacentric height 1.9 ft / 0.6 m
Roll period: 12.1 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.31
Seaboat quality (Average = 1.00): 1.20

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.449
Length to Beam Ratio: 9.75 : 1
'Natural speed' for length: 19.75 kts
Power going to wave formation at top speed: 63 %
Trim (Max stability = 0, Max steadiness = 100): 58
Bow angle (Positive = bow angles forward): 25.00 degrees
Stern overhang: 1.00 ft / 0.30 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 22.00 ft / 6.71 m
- Forecastle (20 %): 16.00 ft / 4.88 m
- Mid (50 %): 16.00 ft / 4.88 m
- Quarterdeck (15 %): 16.00 ft / 4.88 m
- Stern: 16.00 ft / 4.88 m
- Average freeboard: 16.48 ft / 5.02 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 144.8 %
- Above water (accommodation/working, high = better): 137.8 %
Waterplane Area: 9,943 Square feet or 924 Square metres
Displacement factor (Displacement / loading): 97 %
Structure weight / hull surface area: 38 lbs/sq ft or 185 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 1.60
- Overall: 0.56
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
Good seaboat, rides out heavy weather easily

Refit Changes
120mm mounts replaced by one 130mm Mk III DP mount and one 115mm Mk III DP mount
Removal of upper torpedo tube mount
Removal of Z mount
New main director
Addition of RDF
Addition of new boilers and tubines
Addition of 1,000hp diesel engine to drive third shaft (max speed 11 kts on diesel)
New deckhouse aft with accomodation for 50 cadets and classroom
Landing spot abve deckhouse
Refurbishment of internal fittings

Misc Weight Breakdown
9 tons for one quad torpedo mount and four torpedoes
15 tons RDF
100 tons for accomodation for 50 cadets
26 tons for diesel and gearbox
25 tons for strengthened deck for landing spot
5 tons for classroom spaces

The former Margay Class as they will look in Argentine service (the basic destroyer version).

This is an idea I've had musing over using a 130mm twin DP mount on the cruiser to save weight. Secondaries trimmed down to 100mm deck mounts. Does this have any merits over the 150mm armed ship or is it a saving too far?

Project 326P, Argentina Light Cruiser laid down 1942

Displacement:
7,256 t light; 7,571 t standard; 8,389 t normal; 9,043 t full load

Dimensions: Length overall / water x beam x draught
566.09 ft / 557.74 ft x 55.77 ft x 19.03 ft (normal load)
172.55 m / 170.00 m x 17.00 m x 5.80 m

Armament:
8 - 5.12" / 130 mm guns (4x2 guns), 68.34lbs / 31.00kg shells, 1941 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, evenly spread, 2 raised mounts - superfiring
8 - 3.94" / 100 mm guns (4x2 guns), 30.00lbs / 13.61kg shells, 1936 Model
Dual purpose guns in deck mounts
on side ends, evenly spread
12 - 1.46" / 37.0 mm guns (6x2 guns), 1.55lbs / 0.70kg shells, 1940 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
12 - 0.79" / 20.0 mm guns (6x2 guns), 0.24lbs / 0.11kg shells, 1936 Model
Anti-aircraft guns in deck mounts
on side ends, evenly spread, all raised mounts - superfiring
Weight of broadside 808 lbs / 367 kg
Shells per gun, main battery: 300
6 - 23.6" / 600 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 3.94" / 100 mm 328.08 ft / 100.00 m 9.84 ft / 3.00 m
Ends: Unarmoured
Main Belt covers 90 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 3.94" / 100 mm 2.95" / 75 mm 1.97" / 50 mm
2nd: 1.97" / 50 mm 0.98" / 25 mm -
3rd: 0.39" / 10 mm - -
4th: 0.47" / 12 mm - -

- Armour deck: 1.97" / 50 mm, Conning tower: 0.98" / 25 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 72,000 shp / 53,712 Kw = 32.57 kts
Range 8,250nm at 15.00 kts
Bunker at max displacement = 1,471 tons

Complement:
437 - 569

Cost:
£3.828 million / $15.310 million

Distribution of weights at normal displacement:
Armament: 100 tons, 1.2 %
Armour: 1,543 tons, 18.4 %
- Belts: 537 tons, 6.4 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 215 tons, 2.6 %
- Armour Deck: 782 tons, 9.3 %
- Conning Tower: 9 tons, 0.1 %
Machinery: 1,881 tons, 22.4 %
Hull, fittings & equipment: 3,532 tons, 42.1 %
Fuel, ammunition & stores: 1,133 tons, 13.5 %
Miscellaneous weights: 200 tons, 2.4 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
14,422 lbs / 6,542 Kg = 215.1 x 5.1 " / 130 mm shells or 1.8 torpedoes
Stability (Unstable if below 1.00): 1.21
Metacentric height 2.9 ft / 0.9 m
Roll period: 13.7 seconds
Steadiness - As gun platform (Average = 50 %): 60 %
- Recoil effect (Restricted arc if above 1.00): 0.31
Seaboat quality (Average = 1.00): 1.62

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.496
Length to Beam Ratio: 10.00 : 1
'Natural speed' for length: 26.96 kts
Power going to wave formation at top speed: 58 %
Trim (Max stability = 0, Max steadiness = 100): 37
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: 31.17 ft / 9.50 m
- Forecastle (20 %): 24.61 ft / 7.50 m
- Mid (45 %): 22.97 ft / 7.00 m
- Quarterdeck (15 %): 22.97 ft / 7.00 m
- Stern: 22.97 ft / 7.00 m
- Average freeboard: 24.02 ft / 7.32 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 86.2 %
- Above water (accommodation/working, high = better): 181.3 %
Waterplane Area: 21,474 Square feet or 1,995 Square metres
Displacement factor (Displacement / loading): 133 %
Structure weight / hull surface area: 88 lbs/sq ft or 431 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.89
- Longitudinal: 2.70
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Class Names: Santisima Trinidad, Moreno, Rivadavia, Fortaleza, Delante

Misc Weight:
28 tons for two triple torpedo mounts and twelve 600mm torpdoes
75 tons for one catapult and two aircraft
10 tons air conditioning and heating
25 tons for two RDF sets
20 tons for additional equipment in command spaces
40 tons for growth

My first reaction is that she's under-armed for a 7300 ton light cruiser, or over-sized for a eight-gunned flak cruiser. I realize that the secondary battery of 100mm guns enhances the latter role, but IMHO, a vessel of that size warrants a heavier main gun.

On technical merits I like the design, strong, stable and not too fast. I suppose it's my prejudices showing.

I think I agree with Bruce.

By the way, the ex-Margays look pretty neat.

6 twins on the centerline would give a pretty formidable broadside for either the anti-surface or anti-aircraft roles.

Quoted

Originally posted by Brockpaine
I think I agree with Bruce.

By the way, the ex-Margays look pretty neat.

Seconded, very sweet!

Quoted

Originally posted by Hood

The former Margay Class as they will look in Argentine service (the basic destroyer version).

Cool pic. I admire their balanced look a lot.

Have you considered raising the forward stack a bit to make sure the bridge and RF are smoke free?

Thanks Hoo, it could be done. Might be a good idea.

Here are the future Project 326A Class light cruisers.

Hmm...

There's something that's just kinda not working yet to my mind; it's like the aft superstructure's taller than the forward superstructure, almost like she's down by the bow or something. But then it's got that giant mast forward, too.

Another nice drawing, although this one is not as good as your others. Somehow the ship does ot seem to be in balance optically. The bridge is too low compared to an aft deck house too high - and the large gap amidship does not help it. She reminds me a lot of my own old CA26-class. Same "problem" there.

Heh, looks like Hoo and I are seeing the same thing.

On a second thought, looking at that long bo - try moving ALL her superstructure, turrets etc. forward. That should easily solve the issue and make for a nice ship.

Quoted

Originally posted by Brockpaine
Heh, looks like Hoo and I are seeing the same thing. :P

Good to know it´s not MY eyes then.... ;o)