Inti & Illapa rebuilt

[Jefgte]

Here is a study to rebuilt the PDNs Inti & Illapa to Escort Cruiser

- Change old complex reciprocating steam engines to turbines with geared box.
- Speed update to 21.2kts & classic 7000nm@12kts
- Change the old 12x6"casemates to 6xT1x230.
- Change 12x90 to 4M2x120
- Add 40mm AA

Cost 2.42BP & 5.571$



Uploaded with ImageShack.us

Inti - Illapa, Peru BB laid down 1901 (Engine 1916)
Commissioned in 1904 & 1906

Displacement:
   10 000 t light; 10 587 t standard; 11 379 t normal; 12 012 t full load

Dimensions: Length overall / water x beam x draught
   418.52 ft / 416.67 ft x 75.46 ft x 21.65 ft (normal load)
   127.56 m / 127.00 m x 23.00 m  x 6.60 m

Armament:
     4 - 12.01" / 305 mm guns (2x2 guns), 865.70lbs / 392.67kg shells, 1901 Model
     Breech loading guns in turrets (on barbettes)
     on centreline, evenly spread
     6 - 9.06" / 230 mm guns in single mounts, 371.24lbs / 168.39kg shells, 1901 Model
     Breech loading guns in deck mounts with hoists
     on side, evenly spread
     8 - 4.72" / 120 mm guns (4x2 guns), 52.72lbs / 23.91kg shells, 1916 Model
     Breech loading guns in deck mounts with hoists
     on side, evenly spread, all raised mounts
     4 - 1.57" / 40.0 mm guns (2x2 guns), 1.95lbs / 0.88kg shells, 1916 Model
     Quick firing guns in deck mounts
     on side, evenly spread, all raised mounts
     4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1901 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 6 120 lbs / 2 776 kg
   Shells per gun, main battery: 100

Armour:
  - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   9.84" / 250 mm   275.59 ft / 84.00 m   10.17 ft / 3.10 m
   Ends:   4.02" / 102 mm   124.67 ft / 38.00 m   10.17 ft / 3.10 m
     16.40 ft / 5.00 m Unarmoured ends
   Upper:   5.00" / 127 mm   275.59 ft / 84.00 m   8.01 ft / 2.44 m
     Main Belt covers 102 % of normal length

  - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   11.0" / 280 mm   3.94" / 100 mm      9.06" / 230 mm
   2nd:   5.00" / 127 mm   1.18" / 30 mm      1.97" / 50 mm
   3rd:   3.15" / 80 mm   1.18" / 30 mm      1.97" / 50 mm
   4th:   0.79" / 20 mm         -               -
   5th:   0.50" / 13 mm         -               -

  - Armour deck: 2.56" / 65 mm, Conning tower: 9.06" / 230 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 22 999 shp / 17 157 Kw = 21.27 kts
   Range 7 250nm at 12.00 kts
   Bunker at max displacement = 1 425 tons

Complement:
   550 - 716

Cost:
   £1.113 million / $4.450 million

Distribution of weights at normal displacement:
   Armament: 765 tons, 6.7 %
   Armour: 3 782 tons, 33.2 %
      - Belts: 1 897 tons, 16.7 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 713 tons, 6.3 %
      - Armour Deck: 1 073 tons, 9.4 %
      - Conning Tower: 99 tons, 0.9 %
   Machinery: 857 tons, 7.5 %
   Hull, fittings & equipment: 4 286 tons, 37.7 %
   Fuel, ammunition & stores: 1 378 tons, 12.1 %
   Miscellaneous weights: 310 tons, 2.7 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     13 722 lbs / 6 224 Kg = 15.9 x 12.0 " / 305 mm shells or 2.3 torpedoes
   Stability (Unstable if below 1.00): 1.14
   Metacentric height 4.2 ft / 1.3 m
   Roll period: 15.5 seconds
   Steadiness   - As gun platform (Average = 50 %): 52 %
         - Recoil effect (Restricted arc if above 1.00): 0.50
   Seaboat quality  (Average = 1.00): 1.04

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.585
   Length to Beam Ratio: 5.52 : 1
   'Natural speed' for length: 20.41 kts
   Power going to wave formation at top speed: 54 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 5.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      21.13 ft / 6.44 m
      - Forecastle (18 %):   17.52 ft / 5.34 m (13.91 ft / 4.24 m aft of break)
      - Mid (50 %):      13.58 ft / 4.14 m
      - Quarterdeck (18 %):   13.58 ft / 4.14 m
      - Stern:      13.58 ft / 4.14 m
      - Average freeboard:   14.60 ft / 4.45 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 78.2 %
      - Above water (accommodation/working, high = better): 107.3 %
   Waterplane Area: 22 675 Square feet or 2 107 Square metres
   Displacement factor (Displacement / loading): 95 %
   Structure weight / hull surface area: 140 lbs/sq ft or 684 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.92
      - Longitudinal: 1.92
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is adequate

Better view of the rebuilt



Uploaded with ImageShack.us
--------------------------
& the originaly built

Inti - Illapa, Peru BB laid down 1901 (Engine 1900)

Displacement:
   10 400 t light; 10 927 t standard; 11 628 t normal; 12 189 t full load

Dimensions: Length overall / water x beam x draught
   416.67 ft / 416.67 ft x 75.46 ft x 22.13 ft (normal load)
   127.00 m / 127.00 m x 23.00 m  x 6.74 m

Armament:
     4 - 12.01" / 305 mm guns (2x2 guns), 865.70lbs / 392.67kg shells, 1901 Model
     Breech loading guns in turrets (on barbettes)
     on centreline, evenly spread
     12 - 5.98" / 152 mm guns in single mounts, 107.15lbs / 48.60kg shells, 1901 Model
     Breech loading guns in casemate mounts
     on side, evenly spread
     12 - 3.54" / 90.0 mm guns in single mounts, 22.24lbs / 10.09kg shells, 1901 Model
     Quick firing guns in deck mounts
     on side, evenly spread, all raised mounts
     4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1901 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 5 016 lbs / 2 275 kg
   Shells per gun, main battery: 100
   4 - 18.0" / 457.2 mm submerged torpedo tubes

Armour:
  - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   9.84" / 250 mm   275.59 ft / 84.00 m   10.17 ft / 3.10 m
   Ends:   4.02" / 102 mm   124.67 ft / 38.00 m   10.17 ft / 3.10 m
     16.40 ft / 5.00 m Unarmoured ends
   Upper:   5.00" / 127 mm   275.59 ft / 84.00 m   8.01 ft / 2.44 m
     Main Belt covers 102 % of normal length

  - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   11.0" / 280 mm   3.94" / 100 mm      9.06" / 230 mm
   2nd:   5.00" / 127 mm         -               -
   3rd:   0.79" / 20 mm         -               -

  - Armour deck: 2.56" / 65 mm, Conning tower: 9.06" / 230 mm

Machinery:
   Coal fired boilers, complex reciprocating steam engines,
   Direct drive, 2 shafts, 11 912 ihp / 8 886 Kw = 17.92 kts
   Range 4 500nm at 10.00 kts
   Bunker at max displacement = 1 261 tons (100% coal)

Complement:
   559 - 727

Cost:
   £1.151 million / $4.605 million

Distribution of weights at normal displacement:
   Armament: 627 tons, 5.4 %
   Armour: 3 832 tons, 33.0 %
      - Belts: 1 897 tons, 16.3 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 762 tons, 6.6 %
      - Armour Deck: 1 073 tons, 9.2 %
      - Conning Tower: 100 tons, 0.9 %
   Machinery: 1 861 tons, 16.0 %
   Hull, fittings & equipment: 3 789 tons, 32.6 %
   Fuel, ammunition & stores: 1 228 tons, 10.6 %
   Miscellaneous weights: 290 tons, 2.5 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     11 405 lbs / 5 173 Kg = 13.2 x 12.0 " / 305 mm shells or 1.7 torpedoes
   Stability (Unstable if below 1.00): 1.27
   Metacentric height 5.1 ft / 1.5 m
   Roll period: 14.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 73 %
         - Recoil effect (Restricted arc if above 1.00): 0.34
   Seaboat quality  (Average = 1.00): 1.47

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.585
   Length to Beam Ratio: 5.52 : 1
   'Natural speed' for length: 20.41 kts
   Power going to wave formation at top speed: 45 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   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:      16.73 ft / 5.10 m
      - Forecastle (18 %):   13.45 ft / 4.10 m
      - Mid (50 %):      13.12 ft / 4.00 m
      - Quarterdeck (18 %):   13.12 ft / 4.00 m
      - Stern:      13.12 ft / 4.00 m
      - Average freeboard:   13.47 ft / 4.11 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 99.8 %
      - Above water (accommodation/working, high = better): 102.0 %
   Waterplane Area: 22 675 Square feet or 2 107 Square metres
   Displacement factor (Displacement / loading): 90 %
   Structure weight / hull surface area: 125 lbs/sq ft or 610 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.95
      - Longitudinal: 1.66
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is adequate
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

Inti- Ld 1901 - engine 1902 - in service 1904
Illapa - Ld 1903 - engine 1904 - in service 1906

[eltf177]

Very nice upgrade. The big question is - are you getting value for your money? If this rebuild extends their service life another decade or so it's probably cheaper and quicker than scrapping and building new ships.

[Jefgte]

...building new ships

What kind of ships?

I have balanced the efficiency / time / cost:

- I have noted the transfert time from Atlantic to Pacific - 12 days - to have a battle squadron (21-22kts).

- Actualy, the "18kts coal fleet" is unable to work as a part of a 21-22kts battle squadron.

-I have much coasts in South America to protect.

- Built other 21-22kts Battleships take much time, not really neccessary & is expensive for NUS.

- Rebuilt from coal to oil the 1905 PDNs & the 1908 ACs is a possibility.

-The rebuilt "ll be in the same spirit as Iberia made a few years with her ships.

- The cost must be judiciously calculated.

- I am going to test some SS to see what I can do with them...

----------------
Actualy the total cost calculated to rebuilt 5 ships of the "18kts coal fleet" is 9.35BPs

[mentat]

- are the 230mm from existing stock - it creates mixed heavy battery ......

    1 alternative - 1 ship ALL 230mm ( 2x2, 6x1), 1 ship ALL 305mm (2 x2, 4 x1 ?)  - but more expensive

[Jefgte]

I must built T1x230

The first SS with 2T2x12" +4T1x12" give 11560t & 11611t with 4T2x12"

Mixed battery is not a problem, the 2 groups of turrets fired alternatively with the same director of fire.

The max range is 23000m.

[mentat]

  interesting solution on the mixed battery - plan to use dye as well?

it means loading cycles need to be in line - but given the 305s are in turret and 230s in mount + hoist - seems quite compatible (mount + hoist is not ideal for 370 lb shells !)

one aspect of mixed battery can be useful - depending on target - e.g. for Heavy Target could use AP 305 and 230 HE

- what is plan on type of shells carried + use by type of target?

[Jefgte]

..and 230s in mount + hoist - seems quite compatible (mount + hoist is not ideal for 370 lb shells !)...

Mount & hoist... that's a SS typo mistake
That is not M1x230 but T1x230.

About shells; 305 AP & 230 HE is correct I think

[Jefgte]

update

Inti - Illapa, Peru BB laid down 1901 (Engine 1916)

Displacement:
   10 120 t light; 10 709 t standard; 11 506 t normal; 12 144 t full load

Dimensions: Length overall / water x beam x draught
   418.44 ft / 416.67 ft x 75.46 ft x 21.89 ft (normal load)
   127.54 m / 127.00 m x 23.00 m  x 6.67 m

Armament:
      4 - 12.01" / 305 mm guns (2x2 guns), 865.70lbs / 392.67kg shells, 1901 Model
     Breech loading guns in turrets (on barbettes)
     on centreline, evenly spread
      6 - 9.06" / 230 mm guns in single mounts, 371.24lbs / 168.39kg shells, 1901 Model
     Breech loading guns in turrets (on barbettes)
     on side, evenly spread
      8 - 4.72" / 120 mm guns (4x2 guns), 52.72lbs / 23.91kg shells, 1916 Model
     Breech loading guns in deck mounts with hoists
     on side, evenly spread, all raised mounts
      4 - 1.57" / 40.0 mm guns (2x2 guns), 1.95lbs / 0.88kg shells, 1916 Model
     Quick firing guns in deck mounts
     on side, evenly spread, all raised mounts
      4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1901 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 6 120 lbs / 2 776 kg
   Shells per gun, main battery: 100

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   9.84" / 250 mm   275.59 ft / 84.00 m   10.17 ft / 3.10 m
   Ends:   4.02" / 102 mm   124.67 ft / 38.00 m   10.17 ft / 3.10 m
     16.40 ft / 5.00 m Unarmoured ends
   Upper:   5.00" / 127 mm   275.59 ft / 84.00 m   8.01 ft / 2.44 m
     Main Belt covers 102 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   11.0" / 280 mm   3.94" / 100 mm      9.06" / 230 mm
   2nd:   4.72" / 120 mm   2.36" / 60 mm      1.97" / 50 mm
   3rd:   2.76" / 70 mm   1.18" / 30 mm      1.97" / 50 mm
   4th:   0.79" / 20 mm         -               -
   5th:   0.50" / 13 mm         -               -

   - Armour deck: 2.56" / 65 mm, Conning tower: 9.06" / 230 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 23 000 shp / 17 158 Kw = 21.24 kts
   Range 7 250nm at 12.00 kts
   Bunker at max displacement = 1 434 tons

Complement:
   555 - 722

Cost:
   £1.117 million / $4.467 million

Distribution of weights at normal displacement:
   Armament: 765 tons, 6.6 %
   Armour: 3 889 tons, 33.8 %
      - Belts: 1 897 tons, 16.5 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 819 tons, 7.1 %
      - Armour Deck: 1 073 tons, 9.3 %
      - Conning Tower: 99 tons, 0.9 %
   Machinery: 857 tons, 7.4 %
   Hull, fittings & equipment: 4 293 tons, 37.3 %
   Fuel, ammunition & stores: 1 386 tons, 12.0 %
   Miscellaneous weights: 316 tons, 2.7 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     13 781 lbs / 6 251 Kg = 15.9 x 12.0 " / 305 mm shells or 2.3 torpedoes
   Stability (Unstable if below 1.00): 1.12
   Metacentric height 4.1 ft / 1.2 m
   Roll period: 15.7 seconds
   Steadiness   - As gun platform (Average = 50 %): 51 %
         - Recoil effect (Restricted arc if above 1.00): 0.49
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.585
   Length to Beam Ratio: 5.52 : 1
   'Natural speed' for length: 20.41 kts
   Power going to wave formation at top speed: 54 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 5.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      20.24 ft / 6.17 m
      - Forecastle (18 %):   16.96 ft / 5.17 m (13.68 ft / 4.17 m aft of break)
      - Mid (50 %):      13.35 ft / 4.07 m
      - Quarterdeck (18 %):   13.35 ft / 4.07 m
      - Stern:      13.35 ft / 4.07 m
      - Average freeboard:   14.29 ft / 4.36 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 77.4 %
      - Above water (accommodation/working, high = better): 104.6 %
   Waterplane Area: 22 675 Square feet or 2 107 Square metres
   Displacement factor (Displacement / loading): 96 %
   Structure weight / hull surface area: 140 lbs/sq ft or 686 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.93
      - Longitudinal: 1.88
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is adequate

Inti- Ld 1901 - engine 1902 - com 1904 - rebuilt 1921
Illapa - Ld 1903 - engine 1904 - com 1906 - rebuilt 1922

Cost:2.5BP & 5.528$