Lauri Class Cruisers

[snip]

The most modern cruisers in the Imperial Navy in 1910, the Lauri class represent a large increase in speed (via pure oil firing) and torpedo armament (triple tubes supplanting singles). They are also the first cruisers to be equipped with Fire Control.

Four Ships:
--IRS Lauri (Sunk August 1914)
--IRS Isca (Sunk August 1914)
--IRS Dubrae (Sunk August 1914)
--IRS Caletum (Sunk August 1914)

Lauri, Imperial Roman Republic Cruiser laid down 1908

Displacement:
   4,550 t light; 4,708 t standard; 5,171 t normal; 5,541 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (459.31 ft / 452.76 ft) x 47.57 ft x (16.40 / 17.30 ft)
   (140.00 m / 138.00 m) x 14.50 m  x (5.00 / 5.27 m)

Armament:
      7 - 5.51" / 140 mm 50.0 cal guns - 85.98lbs / 39.00kg shells, 150 per gun
     Quick firing guns in deck and hoist mounts, 1902 Model
     5 x Single mounts on centreline ends, majority aft
      2 raised mounts - superfiring
     2 x Single mounts on sides, forward deck aft
      4 - 2.95" / 75.0 mm 50.0 cal guns - 13.23lbs / 6.00kg shells, 150 per gun
     Quick firing guns in deck and hoist mounts, 1902 Model
     4 x Single mounts on sides, aft evenly spread
      4 raised mounts
      Weight of broadside 655 lbs / 297 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   1.97" / 50 mm   377.30 ft / 115.00 m   8.20 ft / 2.50 m
   Ends:   0.98" / 25 mm     75.46 ft / 23.00 m   8.20 ft / 2.50 m
     Main Belt covers 128 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.97" / 50 mm         -         0.98" / 25 mm

   - Protected deck - single deck:
   For and Aft decks: 2.76" / 70 mm
   Forecastle: 1.18" / 30 mm  Quarter deck: 1.18" / 30 mm

   - Conning towers: Forward 3.94" / 100 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 4 shafts, 34,000 shp / 25,364 Kw = 27.42 kts
   Range 7,000nm at 10.00 kts
   Bunker at max displacement = 833 tons

Complement:
   304 - 396

Cost:
   £0.471 million / $1.884 million

Distribution of weights at normal displacement:
   Armament: 202 tons, 3.9 %
      - Guns: 202 tons, 3.9 %
   Armour: 994 tons, 19.2 %
      - Belts: 264 tons, 5.1 %
      - Armament: 39 tons, 0.7 %
      - Armour Deck: 667 tons, 12.9 %
      - Conning Tower: 25 tons, 0.5 %
   Machinery: 1,717 tons, 33.2 %
   Hull, fittings & equipment: 1,462 tons, 28.3 %
   Fuel, ammunition & stores: 621 tons, 12.0 %
   Miscellaneous weights: 175 tons, 3.4 %
      - Hull below water: 5 tons
      - Hull above water: 50 tons
      - On freeboard deck: 105 tons
      - Above deck: 15 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     3,837 lbs / 1,740 Kg = 45.8 x 5.5 " / 140 mm shells or 0.8 torpedoes
   Stability (Unstable if below 1.00): 1.29
   Metacentric height 2.6 ft / 0.8 m
   Roll period: 12.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.28
   Seaboat quality  (Average = 1.00): 1.07

Hull form characteristics:
   Hull has rise forward of midbreak,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.512 / 0.521
   Length to Beam Ratio: 9.52 : 1
   'Natural speed' for length: 21.28 kts
   Power going to wave formation at top speed: 56 %
   Trim (Max stability = 0, Max steadiness = 100): 47
   Bow angle (Positive = bow angles forward): 15.00 degrees
   Stern overhang: 1.28 ft / 0.39 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  19.69 ft / 6.00 m,  19.69 ft / 6.00 m
      - Forward deck:   25.00 %,  19.69 ft / 6.00 m,  19.69 ft / 6.00 m
      - Aft deck:   40.00 %,  10.66 ft / 3.25 m,  10.66 ft / 3.25 m
      - Quarter deck:   15.00 %,  10.66 ft / 3.25 m,  10.66 ft / 3.25 m
      - Average freeboard:      14.72 ft / 4.49 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 121.6 %
      - Above water (accommodation/working, high = better): 128.5 %
   Waterplane Area: 14,511 Square feet or 1,348 Square metres
   Displacement factor (Displacement / loading): 98 %
   Structure weight / hull surface area: 69 lbs/sq ft or 335 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.88
      - Longitudinal: 1.12
      - Overall: 0.90
   Caution: Hull subject to strain in open-sea
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room

Misc Distribution
--Below Water (5t)
----5t Additional Pumps
--Above Water (40t)
----10t Improved Officer Accommodations
----10t Improved Crew Accommodations
----10t Short-Range Wireless
----5t Improved Ventilation
----5t Construction Reserve
--On Deck (105t)
----24t 12x450mm Torpedos (45 Pattern B) [Two Tripple tube mounts per side]
----25t 1906 Fire Control
----25t Long-Range Wireless
----6t Improved Torpedo Handling Equipment
----5t Additional Officer accommodations
----15t Construction Reserve
--Above Deck (15t)
----10t Improved Aquisition Structures
----5t Additional Searchlights

[snip]

In 1913, all four ships of this class received updates in 1912 Fire Control and 530mm torpedo tubes. All four were sunk in August of 1914 at the Battle of Ironclad Bay in this configuration.

Lauri, Imperial Roman Republic Cruiser laid down 1908

Displacement:
   4,550 t light; 4,708 t standard; 5,171 t normal; 5,541 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (459.31 ft / 452.76 ft) x 47.57 ft x (16.40 / 17.30 ft)
   (140.00 m / 138.00 m) x 14.50 m  x (5.00 / 5.27 m)

Armament:
      7 - 5.51" / 140 mm 50.0 cal guns - 85.98lbs / 39.00kg shells, 150 per gun
     Quick firing guns in deck and hoist mounts, 1902 Model
     5 x Single mounts on centreline ends, majority aft
      2 raised mounts - superfiring
     2 x Single mounts on sides, forward deck aft
      4 - 2.95" / 75.0 mm 50.0 cal guns - 13.23lbs / 6.00kg shells, 150 per gun
     Quick firing guns in deck and hoist mounts, 1902 Model
     4 x Single mounts on sides, aft evenly spread
      4 raised mounts
      Weight of broadside 655 lbs / 297 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   1.97" / 50 mm   377.30 ft / 115.00 m   8.20 ft / 2.50 m
   Ends:   0.98" / 25 mm     75.46 ft / 23.00 m   8.20 ft / 2.50 m
     Main Belt covers 128 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.97" / 50 mm         -         0.98" / 25 mm

   - Protected deck - single deck:
   For and Aft decks: 2.76" / 70 mm
   Forecastle: 1.18" / 30 mm  Quarter deck: 1.18" / 30 mm

   - Conning towers: Forward 3.94" / 100 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 4 shafts, 34,000 shp / 25,364 Kw = 27.42 kts
   Range 7,000nm at 10.00 kts
   Bunker at max displacement = 833 tons

Complement:
   304 - 396

Cost:
   £0.471 million / $1.884 million

Distribution of weights at normal displacement:
   Armament: 202 tons, 3.9 %
      - Guns: 202 tons, 3.9 %
   Armour: 994 tons, 19.2 %
      - Belts: 264 tons, 5.1 %
      - Armament: 39 tons, 0.7 %
      - Armour Deck: 667 tons, 12.9 %
      - Conning Tower: 25 tons, 0.5 %
   Machinery: 1,717 tons, 33.2 %
   Hull, fittings & equipment: 1,462 tons, 28.3 %
   Fuel, ammunition & stores: 621 tons, 12.0 %
   Miscellaneous weights: 175 tons, 3.4 %
      - Hull below water: 5 tons
      - Hull above water: 50 tons
      - On freeboard deck: 105 tons
      - Above deck: 15 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     3,837 lbs / 1,740 Kg = 45.8 x 5.5 " / 140 mm shells or 0.8 torpedoes
   Stability (Unstable if below 1.00): 1.29
   Metacentric height 2.6 ft / 0.8 m
   Roll period: 12.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.28
   Seaboat quality  (Average = 1.00): 1.07

Hull form characteristics:
   Hull has rise forward of midbreak,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.512 / 0.521
   Length to Beam Ratio: 9.52 : 1
   'Natural speed' for length: 21.28 kts
   Power going to wave formation at top speed: 56 %
   Trim (Max stability = 0, Max steadiness = 100): 47
   Bow angle (Positive = bow angles forward): 15.00 degrees
   Stern overhang: 1.28 ft / 0.39 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  19.69 ft / 6.00 m,  19.69 ft / 6.00 m
      - Forward deck:   25.00 %,  19.69 ft / 6.00 m,  19.69 ft / 6.00 m
      - Aft deck:   40.00 %,  10.66 ft / 3.25 m,  10.66 ft / 3.25 m
      - Quarter deck:   15.00 %,  10.66 ft / 3.25 m,  10.66 ft / 3.25 m
      - Average freeboard:      14.72 ft / 4.49 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 121.6 %
      - Above water (accommodation/working, high = better): 128.5 %
   Waterplane Area: 14,511 Square feet or 1,348 Square metres
   Displacement factor (Displacement / loading): 98 %
   Structure weight / hull surface area: 69 lbs/sq ft or 335 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.88
      - Longitudinal: 1.12
      - Overall: 0.90
   Caution: Hull subject to strain in open-sea
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room

Misc Distribution
--Below Water (5t)
----5t Additional Pumps
--Above Water (40t)
----10t Improved Officer Accommodations
----10t Improved Crew Accommodations
----10t Short-Range Wireless
----5t Improved Ventilation
----5t Construction Reserve
--On Deck (105t)
----36t 12x530mm Torpedos [Two Tripple tube mounts per side]
----25t 1912 Fire Control
----25t Long-Range Wireless
----6t Improved Torpedo Handling Equipment
----5t Additional Officer accommodations
----3t Construction Reserve
--Above Deck (15t)
----10t Improved Aquisition Structures
----5t Additional Searchlights