Netherlands auxiliaries

[Korpen]

A first design digesting some of the experiences of the late war.
The ship is designed to carry one regiment of marines combat loaded. The speed and range of her is in line with that of the main fleet speed.
A total of five ships should be enough to carry an entire division (one for each regiment, and two for the train and supply units) from port to invasion area.
The Misc weight breakdown: 1000ton for the line infantry (three battalion á 300 infantry), 300 tons for the pioneer battalion, 250 ton for the artillery battalion (six 77mm, three 105 howitzers) with crew and traction, 300 ton for supply units and supplies and finally 150 tons for six motor launches to allow faster disembarkation.

It should be noted that the ship is not intended for strategic transports, for that she is a bit too cramped at full load.

Modell Ia, Netherlands 1BP transport laid down 1909

Displacement:
   4 000 t light; 4 117 t standard; 4 804 t normal; 5 354 t full load

Dimensions: Length overall / water x beam x draught
   355,05 ft / 355,05 ft x 52,49 ft x 16,40 ft (normal load)
   108,22 m / 108,22 m x 16,00 m  x 5,00 m

Armament:
      8 - 3,46" / 88,0 mm guns in single mounts, 19,84lbs / 9,00kg shells, 1909 Model
     Quick firing guns in deck mounts
     on side, evenly spread
      2 - 3,94" / 100 mm guns in single mounts, 37,48lbs / 17,00kg shells, 1909 Model
     Breech loading guns in deck mounts
     on centreline ends, evenly spread
   Weight of broadside 234 lbs / 106 kg
   Shells per gun, main battery: 150

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 13 069 shp / 9 749 Kw = 21,00 kts
   Range 8 000nm at 12,00 kts
   Bunker at max displacement = 1 237 tons

Complement:
   288 - 375

Cost:
   £0,247 million / $0,988 million

Distribution of weights at normal displacement:
   Armament: 28 tons, 0,6 %
   Machinery: 594 tons, 12,4 %
   Hull, fittings & equipment: 1 347 tons, 28,0 %
   Fuel, ammunition & stores: 805 tons, 16,7 %
   Miscellaneous weights: 2 030 tons, 42,3 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     6 253 lbs / 2 836 Kg = 300,7 x 3,5 " / 88 mm shells or 1,3 torpedoes
   Stability (Unstable if below 1.00): 1,09
   Metacentric height 2,3 ft / 0,7 m
   Roll period: 14,7 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0,05
   Seaboat quality  (Average = 1.00): 1,61

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,550
   Length to Beam Ratio: 6,76 : 1
   'Natural speed' for length: 18,84 kts
   Power going to wave formation at top speed: 54 %
   Trim (Max stability = 0, Max steadiness = 100): 31
   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 %):   16,40 ft / 5,00 m
      - Mid (50 %):      16,40 ft / 5,00 m
      - Quarterdeck (15 %):   16,40 ft / 5,00 m
      - Stern:      16,40 ft / 5,00 m
      - Average freeboard:   16,80 ft / 5,12 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 91,0 %
      - Above water (accommodation/working, high = better): 141,1 %
   Waterplane Area: 13 007 Square feet or 1 208 Square metres
   Displacement factor (Displacement / loading): 139 %
   Structure weight / hull surface area: 67 lbs/sq ft or 327 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,92
      - Longitudinal: 2,08
      - 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

During the war the Korps Mariniers conducted no less then seven landing operations, of which four was opposed.

[P3D]

A quote from the Warships 1 discussion board about amphibious capabilities.

2.)FWIW, Mark Parillo's book, "The Japanese Merchant Marine in WW2" lists average Japanese ship troop capacities as follow:
2,000 troops & equipment on a 5,000 ton ship, port-to-port
1,000 troops & equipment on a 5,000 ton ship, beach assault

I'd say five such ship would be capable to transport a division only from port-to-port.

[Korpen]

A quote from the Warships 1 discussion board about amphibious capabilities.

2.)FWIW, Mark Parillo's book, "The Japanese Merchant Marine in WW2" lists average Japanese ship troop capacities as follow:
2,000 troops & equipment on a 5,000 ton ship, port-to-port
1,000 troops & equipment on a 5,000 ton ship, beach assault

I'd say five such ship would be capable to transport a division only from port-to-port.

I suspect that the numbers would be very much different on a purpose-designed ship, compared to a ordinary merchant ship used for the same purpose. This due to the fact that troops are volume rather then weight critical (and the reason SS is quite crappy at simming liners and troops ships), and much of the pure volume is accounted for by the freeboard height.

Btw, you did not have a page reference form that book? I thought I was going to take a look at it tomorrow, but I do not think I have time to read it front to back.

[P3D]

Sorry, that's what I had saved, it comes from this thread:
http://warships1discussionboards.yuku.com/topic/765

As in general merchant cargo is also volume-intensive, purpose-built ships offer advantage only in speed and loading/unloading.

I'd suggest not to put too much work in actual figures, especially how many troops could be transported in what tonnage. The moderators have started working on some revised amphibious rules after the war had shown some deficiencies, but nothing is fixed yet.

Current guidelines for handling troop transport is roughly corresponds to the numbers I mentioned, and it is based on several sources. Keep in mind that US AKA transports had a bit better than 1000 troops/10000t capacity. So expect to need around 200-400,000t shipping to combat load a light or heavy infantry corps.

[Korpen]

Sorry, that's what I had saved, it comes from this thread:
http://warships1discussionboards.yuku.com/topic/765

As in general merchant cargo is also volume-intensive, purpose-built ships offer advantage only in speed and loading/unloading.

I'd suggest not to put too much work in actual figures, especially how many troops could be transported in what tonnage. The moderators have started working on some revised amphibious rules after the war had shown some deficiencies, but nothing is fixed yet.

Current guidelines for handling troop transport is roughly corresponds to the numbers I mentioned, and it is based on several sources. Keep in mind that US AKA transports had a bit better than 1000 troops/10000t capacity. So expect to need around 200-400,000t shipping to combat load a light or heavy infantry corps.

Well I can argue further, but if the issue is under debate elsewere i give this ship a miss for the time being, and look forward to som new amphibious rules. :)

But I want to show of the other design, a tactical transport, either for in-shore operations, or for ship to shore operations. She is really too small to work in SS, so take her with a bit of salt. She is based on the much later Swedish Tpbs 200 (Transportbåt Större 200), about the same capability, but on twice the displacement.

Tpbs 200, Netherlands Transport laid down 1909

Displacement:
   65 t light; 67 t standard; 70 t normal; 73 t full load

Dimensions: Length overall / water x beam x draught
   104,99 ft / 104,99 ft x 13,45 ft x 3,94 ft (normal load)
   32,00 m / 32,00 m x 4,10 m  x 1,20 m

Armament:
      1 - 1,97" / 50,0 mm guns in single mounts, 3,81lbs / 1,73kg shells, 1909 Model
     Quick firing gun in deck mount
     on centreline forward
      3 - 0,31" / 8,0 mm guns (2 mounts), 0,02lbs / 0,01kg shells, 1909 Model
     Machine guns in deck mounts
     on side, all amidships, 2 raised mounts - superfiring
   Weight of broadside 4 lbs / 2 kg
   Shells per gun, main battery: 150

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Ends:   0,31" / 8 mm     6,56 ft / 2,00 m   8,20 ft / 2,50 m
     98,43 ft / 30,00 m Unarmoured ends

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,20" / 5 mm         -               -
   2nd:   0,20" / 5 mm         -               -

Machinery:
   Diesel Internal combustion motors,
   Direct drive, 3 shafts, 851 shp / 635 Kw = 18,17 kts
   Range 250nm at 14,05 kts
   Bunker at max displacement = 6 tons

Complement:
   11 - 15

Cost:
   £0,007 million / $0,028 million

Distribution of weights at normal displacement:
   Armament: 0 tons, 0,7 %
   Armour: 1 tons, 1,2 %
      - Belts: 1 tons, 0,9 %
      - Torpedo bulkhead: 0 tons, 0,0 %
      - Armament: 0 tons, 0,3 %
      - Armour Deck: 0 tons, 0,0 %
      - Conning Tower: 0 tons, 0,0 %
   Machinery: 30 tons, 43,0 %
   Hull, fittings & equipment: 22 tons, 32,0 %
   Fuel, ammunition & stores: 5 tons, 7,4 %
   Miscellaneous weights: 11 tons, 15,7 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     31 lbs / 14 Kg = 8,1 x 2,0 " / 50 mm shells or 0,1 torpedoes
   Stability (Unstable if below 1.00): 1,14
   Metacentric height 0,3 ft / 0,1 m
   Roll period: 10,0 seconds
   Steadiness   - As gun platform (Average = 50 %): 60 %
         - Recoil effect (Restricted arc if above 1.00): 0,08
   Seaboat quality  (Average = 1.00): 1,20

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0,441
   Length to Beam Ratio: 7,80 : 1
   'Natural speed' for length: 10,25 kts
   Power going to wave formation at top speed: 69 %
   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:      8,20 ft / 2,50 m
      - Forecastle (20 %):   7,22 ft / 2,20 m (6,89 ft / 2,10 m aft of break)
      - Mid (50 %):      6,56 ft / 2,00 m
      - Quarterdeck (15 %):   6,56 ft / 2,00 m
      - Stern:      6,56 ft / 2,00 m
      - Average freeboard:   6,82 ft / 2,08 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 161,3 %
      - Above water (accommodation/working, high = better): 102,8 %
   Waterplane Area: 894 Square feet or 83 Square metres
   Displacement factor (Displacement / loading): 75 %
   Structure weight / hull surface area: 11 lbs/sq ft or 56 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 4,93
      - Overall: 0,63
   Caution: Hull subject to strain in open-sea
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is adequate
   Good seaboat, rides out heavy weather easily

The armouring of the stern is to give some protection against bullets and shrapnel during an approach on a beach or other objective.
The boast is capable to carry 40 soldiers and 3 tons of cargo.

[Blooded]

Hello,

I stumbled across this today as an example of 1/2 Corps amphibious warfare. This took place in 1917. So a bit in the future (at least 1905 Tech- maybe 1910?).

taken from   http://www.gwpda.org/naval/fdgn0002.htm

The Germans assembled a massive naval force for their amphibious landings on the Baltic islands of Moon and Oesel in the Riga Bay. The landing force was composed of the 42nd Infantry Division, which was reinforced to an oversize strength of 23,000 men. In addition to the troops on board, the transport fleet (made up of 19 large cargo ships displacing a total of 153,660 GRT) was also carrying 5000 horses, 1400 vehicles, and 54 artillery pieces. The German forces reached the landing points in the early of October 12th, 1917. The naval bombardment of the Russian shore batteries commenced at 0420, and the preliminary troop landings took place at 0530. The military occupation of the island group was completed by October 17th......


Some new rules would be nice, I will look forward to them. We will definately need rules on how much misc. space troops and stores need to take up( I have been trying to use 1.5 tons for long distance-5000+ miles, 1 for medium-2000+ miles, and a guess of .5 ton for short distances) the liner rules seem a bit much for amphib work.

As to the patrol boat/transport.
Do you have Amphibious Tech 1905? Looking at your info states you dont yet have 1905. Nor are you researching -unless its secret then it will still be a bit.

11 Misc tons for 40 men and 3 tons cargo seems a bit short(.2 tons per man) and the space they are to fit in on the drawing seems a bit small(the 6' armored box wont help many of them certainly). At 65 tons is she to heavy and large to hitch a ride. How will she get to where you are attacking?

A bit heavily Armed IMO (my first ideas were much the same- 4MGs) and quite quick I would use her as a patrol vessel shes perfect for that(with some range) good seaboat- that would be a big plus. Where do the captain and pilot stand, the top gunner would seem to be in the way?

Anyhow good things to bring up thanks.

[Korpen]

11 Misc tons for 40 men and 3 tons cargo seems a bit short(.2 tons per man) and the space they are to fit in on the drawing seems a bit small(the 6' armored box wont help many of them certainly). At 65 tons is she to heavy and large to hitch a ride. How will she get to where you are attacking?

The cargo space on her is the same size as the space aboard the real tpbs200, so the passengers are sitting on benches along the sides and centre of the compartment.
And at full load, they will be packed like sardines, but a full soldier load will not be carried for more then a few hours at most.

A 75 ton ship is perfectly possible to be carried by another ship, but granted, that ship needs some serious specialisation.

The armour is not a box, but rather a shield and it give pretty good protection for the entire passenger compartment from fire directly ahead, as might be encountered during an assault.

A bit heavily Armed IMO (my first ideas were much the same- 4MGs) and quite quick I would use her as a patrol vessel shes perfect for that(with some range) good seaboat- that would be a big plus. Where do the captain and pilot stand, the top gunner would seem to be in the way?

The heavy armament fulfils two purposes; the main one is to provide fire support during an assault, allowing marines to maintain an advantage of firepower in the landing area.

The second is when the boat is used in an auxiliary role as a patrol boat (mainly in the Malacca region) to give it some anti-ship firepower.

A major thing about the vessel is to simplify raids and tactical operations, not primarily large scale landings. Important is increasing the speed of an operation, and allow landing in more diverse areas, as so far potential landing zones have been restricted, and therefore easily predicted and defended.

[Korpen]

Well, not really a aux as such, but this thread will serve.

The mine rails are also capable to carry cradles for torpedoes, allowing the ship to be used as a torpedo supply ship for a TB flotilla.
Two large doors in the roof of the hangar simplify loading of misc cargo if it should be needed.

A potential drawback is that she does not really carry enough mines to make any major impression on her own.
Any thoughts or feedback?


Displacement:
   750 t light; 776 t standard; 915 t normal; 1 026 t full load

Dimensions: Length overall / water x beam x draught
   280,51 ft / 280,51 ft x 28,05 ft x 9,78 ft (normal load)
   85,50 m / 85,50 m x 8,55 m  x 2,98 m

Armament:
      2 - 4,72" / 120 mm guns in single mounts, 46,30lbs / 21,00kg shells, 1909 Model
     Breech loading guns in deck mounts
     on centreline, all forward, 1 raised mount
      2 - 0,31" / 8,0 mm guns in single mounts, 0,02lbs / 0,01kg shells, 1909 Model
     Machine guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 93 lbs / 42 kg
   Shells per gun, main battery: 140

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,39" / 10 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 14 844 shp / 11 074 Kw = 28,00 kts
   Range 4 330nm at 12,00 kts
   Bunker at max displacement = 251 tons

Complement:
   83 - 108

Cost:
   £0,100 million / $0,400 million

Distribution of weights at normal displacement:
   Armament: 13 tons, 1,4 %
   Armour: 2 tons, 0,2 %
      - Belts: 0 tons, 0,0 %
      - Torpedo bulkhead: 0 tons, 0,0 %
      - Armament: 2 tons, 0,2 %
      - Armour Deck: 0 tons, 0,0 %
      - Conning Tower: 0 tons, 0,0 %
   Machinery: 447 tons, 48,8 %
   Hull, fittings & equipment: 230 tons, 25,1 %
   Fuel, ammunition & stores: 165 tons, 18,0 %
   Miscellaneous weights: 59 tons, 6,4 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     254 lbs / 115 Kg = 4,8 x 4,7 " / 120 mm shells or 0,2 torpedoes
   Stability (Unstable if below 1.00): 1,32
   Metacentric height 1,2 ft / 0,4 m
   Roll period: 10,7 seconds
   Steadiness   - As gun platform (Average = 50 %): 77 %
         - Recoil effect (Restricted arc if above 1.00): 0,16
   Seaboat quality  (Average = 1.00): 1,16

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0,416
   Length to Beam Ratio: 10,00 : 1
   'Natural speed' for length: 16,75 kts
   Power going to wave formation at top speed: 64 %
   Trim (Max stability = 0, Max steadiness = 100): 66
   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:      19,03 ft / 5,80 m
      - Forecastle (15 %):   17,06 ft / 5,20 m
      - Mid (31 %):      17,06 ft / 5,20 m (9,19 ft / 2,80 m aft of break)
      - Quarterdeck (10 %):   9,19 ft / 2,80 m
      - Stern:      9,19 ft / 2,80 m
      - Average freeboard:   11,78 ft / 3,59 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 175,4 %
      - Above water (accommodation/working, high = better): 122,5 %
   Waterplane Area: 4 893 Square feet or 455 Square metres
   Displacement factor (Displacement / loading): 60 %
   Structure weight / hull surface area: 24 lbs/sq ft or 119 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

And in case someone have missed it, Yes, the Netherlands are great belivers in mine warfare... :)

[P3D]

Too low BC for an auxiliary, and could indeed do with a bit more mines. Perhaps cutting speed to 27kts?

[Korpen]

Too low BC for an auxiliary, and could indeed do with a bit more mines. Perhaps cutting speed to 27kts?

The low BC is due to the fact that i wanted to use the same hull as the G-class boats, and the hull of the two types of ships are identical, so these ships would be built under DD rules and costs.

Hm, after some thinking I did take your advice cut speed to 27,2kts (slightly slower then the older Dutch TBs, but on the same level), this allow the ship to increase the number of mines to 80, enough to be more usefull.

[The Rock Doctor]

That would work - I might well try something similar.

BC's perfectly fine - it's a small, fast ship, even if not intended to fight other ships.

[Sachmle]

Maybe cut one of the 120mm and enlarge the 8mm machine gun to something a little heavier like a 20mm. Guessing she's supposed to run away if enemy units encountered and that second 120mm isn't gonna matter much if she has to stay and fight. Saved weight might let you add more mines or increase to 27.5-28knts.

[Korpen]

Maybe cut one of the 120mm and enlarge the 8mm machine gun to something a little heavier like a 20mm. Guessing she's supposed to run away if enemy units encountered and that second 120mm isn't gonna matter much if she has to stay and fight. Saved weight might let you add more mines or increase to 27.5-28knts.

Removing one of the 12cm guns will only allow an increase in speed by about 0,05kts...
In large part this is due to the fact the hull dimensions are fixed, so the weight saved in ammo have to be compensated in more ammo for the remaining one, or more fuel.

And dotrine is to never send minelayers out on missions alone, but to escort them with similar ships.

[Korpen]

Tanker design mentioned in the "Blue ribbon tanker-thread"

For the fleet!, The Kingdom Tanker laid down 1910

Displacement:
   2 100 t light; 2 225 t standard; 6 267 t normal; 9 501 t full load

Dimensions: Length overall / water x beam x draught
   393,70 ft / 393,70 ft x 48,88 ft x 19,69 ft (normal load)
   120,00 m / 120,00 m x 14,90 m  x 6,00 m

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 1 shaft, 16 000 shp / 11 936 Kw = 21,49 kts
   Range 43 720nm at 12,00 kts
   Bunker at max displacement = 7 276 tons
1700 ton for own use = 10 000nm @ 12kts

Complement:
   351 - 457

Cost:
   £0,166 million / $0,664 million

Distribution of weights at normal displacement:
   Armament: 0 tons, 0,0 %
   Machinery: 661 tons, 10,5 %
   Hull, fittings & equipment: 1 359 tons, 21,7 %
   Fuel, ammunition & stores: 4 168 tons, 66,5 %
   Miscellaneous weights: 80 tons, 1,3 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     20 172 lbs / 9 150 Kg = 186,8 x 6 " / 152 mm shells or 4,0 torpedoes
   Stability (Unstable if below 1.00): 2,18
   Metacentric height 5,7 ft / 1,7 m
   Roll period: 8,6 seconds
   Steadiness   - As gun platform (Average = 50 %): 74 %
         - Recoil effect (Restricted arc if above 1.00): 0,00
   Seaboat quality  (Average = 1.00): 1,49

Hull form characteristics:
   Hull has raised forecastle, rise forward of midbreak, raised quarterdeck
   Block coefficient: 0,579
   Length to Beam Ratio: 8,05 : 1
   'Natural speed' for length: 19,84 kts
   Power going to wave formation at top speed: 51 %
   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:      19,69 ft / 6,00 m
      - Forecastle (20 %):   18,04 ft / 5,50 m (9,84 ft / 3,00 m aft of break)
      - Mid (50 %):      11,48 ft / 3,50 m (9,84 ft / 3,00 m aft of break)
      - Quarterdeck (15 %):   18,04 ft / 5,50 m (9,84 ft / 3,00 m before break)
      - Stern:      18,04 ft / 5,50 m
      - Average freeboard:   13,09 ft / 3,99 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 37,2 %
      - Above water (accommodation/working, high = better): 74,6 %
   Waterplane Area: 13 453 Square feet or 1 250 Square metres
   Displacement factor (Displacement / loading): 447 %
   Structure weight / hull surface area: 63 lbs/sq ft or 309 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,97
      - Longitudinal: 1,28
      - Overall: 1,00
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is cramped
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

The BP cost would then be 1/4 of 1439 (2100-661) + 661 = 1,02 BP if i got things right

[Borys]

Ahoj!
No, the way I understand this is to work is
1,66/4 - 0,44$ for the one fourth
Plus
0,6 BP x2$ = 1,2$

Thus the final cost is 1,64$ and 0,6BP.

Or at least in my understanding.

Borys