Parthian vessels 1916 onwards

[Kaiser Kirk]

Still looking at the 3000 ton category.
The previously posted Artesmia is still my lead candidate for replacing the sailing frigates of the same name.
Long range, excellent speed, heavy QF battery. They can either serve in rear areas doing commerce raiding/protection, or
be brought in to serve as fleet screening and scouting units.

This is a look at a slower, but more robust ship.

I was really hoping for a better speed out of it, but this matches or exceeds existing cruisers.
It won't be faster than the next generation- but it should be years before those exist in large quantities.

One advantage of less speed is less length, so it can fit in smaller docks.

The Parthian 165mm basically is a 1 hit kill for any DD, and is effective against most cruisers out there...
though outgunned by Byzantines cruisers. 

The 2 guns forward can't make an effective spotting ladder, but it can on the broadside.
The single mount & hoist should have traverse rates sufficient for screening.

For some reason I reverted to bow underwater torpedo tubes.
I had some theory on that, which I do not recall.

Porpoise II, Parthian Frigate laid down 1923

Displacement:
   3,000 t light; 3,151 t standard; 3,691 t normal; 4,123 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (392.61 ft / 383.86 ft) x 42.65 ft x (16.40 / 17.82 ft)
   (119.67 m / 117.00 m) x 13.00 m  x (5.00 / 5.43 m)

Armament:
      4 - 6.50" / 165 mm 43.0 cal guns - 143.30lbs / 65.00kg shells, 180 per gun
     Quick firing guns in deck and hoist mounts, 1913 Model
     4 x Single mounts on centreline ends, evenly spread
      2 raised mounts - superfiring
      8 - 2.24" / 57.0 mm 60.0 cal guns - 6.61lbs / 3.00kg shells, 500 per gun
     Anti-air guns in deck and hoist mounts, 1923 Model
     2 x 2-gun mounts on sides forward
     2 x 2-gun mounts on centreline ends, evenly spread
      2 double raised mounts
      16 - 0.59" / 15.0 mm 60.0 cal guns - 0.11lbs / 0.05kg shells, 5,000 per gun
     Machine guns in deck mounts, 1923 Model
     4 x 2 row quad mounts on side ends, evenly spread
      4 double raised mounts
      Weight of broadside 628 lbs / 285 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   1.97" / 50 mm   287.89 ft / 87.75 m   12.01 ft / 3.66 m
   Ends:   Unarmoured
     Main Belt covers 115 % of normal length
     Main Belt inclined 45.00 degrees (positive = in)

   - Hull void:
      0.00" / 0 mm     0.00 ft / 0.00 m   0.00 ft / 0.00 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.38" / 35 mm   1.18" / 30 mm      1.18" / 30 mm
   2nd:   0.31" / 8 mm         -               -

   - Protected deck - single deck:
   For and Aft decks: 1.18" / 30 mm
   Forecastle: 0.98" / 25 mm  Quarter deck: 0.98" / 25 mm

   - Conning towers: Forward 1.18" / 30 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 32,109 shp / 23,953 Kw = 28.00 kts
   Range 8,400nm at 14.00 kts
   Bunker at max displacement = 973 tons

Complement:
   236 - 307

Cost:
   £0.905 million / $3.619 million

Distribution of weights at normal displacement:
   Armament: 157 tons, 4.3 %
      - Guns: 157 tons, 4.3 %
   Armour: 553 tons, 15.0 %
      - Belts: 274 tons, 7.4 %
      - Armament: 41 tons, 1.1 %
      - Armour Deck: 232 tons, 6.3 %
      - Conning Tower: 6 tons, 0.2 %
   Machinery: 1,073 tons, 29.1 %
   Hull, fittings & equipment: 1,007 tons, 27.3 %
   Fuel, ammunition & stores: 691 tons, 18.7 %
   Miscellaneous weights: 209 tons, 5.7 %
      - Hull below water: 48 tons
      - Hull void weights: 25 tons
      - Hull above water: 15 tons
      - On freeboard deck: 28 tons
      - Above deck: 93 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     2,750 lbs / 1,247 Kg = 20.1 x 6.5 " / 165 mm shells or 0.8 torpedoes
   Stability (Unstable if below 1.00): 1.11
   Metacentric height 1.7 ft / 0.5 m
   Roll period: 13.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.70
   Seaboat quality  (Average = 1.00): 1.23

Hull form characteristics:
   Hull has a flush deck,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0.481 / 0.495
   Length to Beam Ratio: 9.00 : 1
   'Natural speed' for length: 19.59 kts
   Power going to wave formation at top speed: 61 %
   Trim (Max stability = 0, Max steadiness = 100): 58
   Bow angle (Positive = bow angles forward): 22.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   15.00 %,  21.65 ft / 6.60 m,  19.52 ft / 5.95 m
      - Forward deck:   20.00 %,  19.52 ft / 5.95 m,  17.06 ft / 5.20 m
      - Aft deck:   55.00 %,  17.06 ft / 5.20 m,  13.78 ft / 4.20 m
      - Quarter deck:   10.00 %,  13.78 ft / 4.20 m,  13.78 ft / 4.20 m
      - Average freeboard:      16.57 ft / 5.05 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 111.2 %
      - Above water (accommodation/working, high = better): 140.1 %
   Waterplane Area: 10,724 Square feet or 996 Square metres
   Displacement factor (Displacement / loading): 107 %
   Structure weight / hull surface area: 56 lbs/sq ft or 272 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.67
      - Longitudinal: 2.00
      - Overall: 0.75
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

Warning: Beam between bulkheads too wide

Intended to replace the aged Dolphin gunboats, the Porpoise was given speed sufficient to work around the battleline.

As a gunboat, it can operate in fairly shallow water,
and act as a patrol vessel.

An alternate version mounting twin 130mm in 'A'& 'X'and a 'B' Howitzer, for enhanced shore bombardment has been considered.

As a Close Escort it would serve as an intermediate screen against MTBs and DDs, while also being equipped to detect and prosecute ASW attacks.

Against attacking destroyers, the powerful 165mm battery is expected to wreck havok. While the light armor is expected to preserve the firepower and floatation of the vessel.

Any offensive role would be at night, possibly as a follow up to an earlier attack. The Hulesmeyer device has not prooved an effective early warning system, but is viewed as promising for night time formation steaming.




            1                   3               
A (B)                               (X) Y
            2                   4


Trying to avoid a 'break' in the hull, with the associated structural costs, the weather deck slopes between fore and stern, loosing 1 m over ~38m, for a 3% slope - barely noticable. The battery deck below is the Protected deck, and strength deck.

With hull space <130%, a Protective deck is fitted

The armor is meant to defeat QF weapons as might be found on destroyers or smaller cruisers outside the Rea Sea.   


A reversion to underwater torpedo tubes sees 2 fitted in the bow, using submarine technology. These are foreward of the main bulkhead, and are proctected by the forward armored deck.





Misc Wt
25t- Reserve

AD
16t -  FC
25t - Night Fighting
25t - LR Radio
25t - Hulesmeyer

OD
3t  : Air conditioning
5t  : Paravanes
10t : Depth charges
10t : Squadron Plot Room

HAW
15t : Extra Fire Fighting

HBW
30t : 2x  Enhanced Hydrophone station
18t : 2 UTT 21" Bow, 6 torps

Decks :
4.2m-5.2m : Weather Deck
1.8m : Protective Deck 
-0.7 m : bottom protective deck
-4.30m : Engineering deck
-5.30 m : Keel, double bottom

[Kaiser Kirk]

So this won't get built.
At 15,700 it's only 2800 tons under a Zemaka, but is far less powerful.

What it was intended to explore is something that
could field the 230L44 gun, with an eye to something
that could reliably engage and sink Jefgte's 191mm cruisers.
Basic Armored cruiser role at minimal cost.

I also wanted a TDS - this has a decent armored bulkhead and depth,
but on a smaller ship, it doesn't give much in torpedo absorption.
It looks like +0.8 torpedoes - but it should protect against criticals.
The trade off there is narrower internal beam forces a longer belt.

I should try a version with no TDS.
Edit : Tried that, allows a 32kt ship and  outsloping the belt.


Anyhow, when considering the vessels already out there,
it is still very expensive as a cruiser hunter, but can't tackle the
old armored cruisers reliably, which the Zemaka class can.

Alan, Parthia Armored Cruiser laid down 1923

Displacement:
   15,700 t light; 16,617 t standard; 18,277 t normal; 19,605 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (589.65 ft / 582.35 ft) x 72.18 ft (Bulges 75.46 ft) x (27.89 / 29.51 ft)
   (179.72 m / 177.50 m) x 22.00 m (Bulges 23.00 m)  x (8.50 / 9.00 m)

Armament:
      8 - 9.06" / 230 mm 44.0 cal guns - 392.42lbs / 178.00kg shells, 180 per gun
     Breech loading guns in turret on barbette mounts, 1913 Model
     4 x 2-gun mounts on centreline ends, evenly spread
      2 raised mounts - superfiring
      16 - 5.12" / 130 mm 50.0 cal guns - 70.55lbs / 32.00kg shells, 250 per gun
     Quick firing guns in deck and hoist mounts, 1913 Model
     4 x 2-gun mounts on side ends, evenly spread
     4 x 2-gun mounts on sides, forward deck aft
      4 raised mounts
      12 - 3.54" / 90.0 mm 50.0 cal guns - 24.25lbs / 11.00kg shells, 400 per gun
     Anti-air guns in deck and hoist mounts, 1911 Model
     4 x 2-gun mounts on side ends, evenly spread
      4 raised mounts
     2 x 2-gun mounts on centreline ends, evenly spread
      2 double raised mounts
      12 - 2.24" / 57.0 mm 60.0 cal guns - 6.61lbs / 3.00kg shells, 350 per gun
     Anti-air guns in deck and hoist mounts, 1919 Model
     2 x 2-gun mounts on sides amidships
     4 x 2-gun mounts on sides, evenly spread
      4 double raised mounts
      16 - 0.59" / 15.0 mm 70.0 cal guns - 0.11lbs / 0.05kg shells, 150 per gun
     Machine guns in deck mounts, 1917 Model
     8 x Single mounts on sides, evenly spread
      Weight of broadside 4,640 lbs / 2,105 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   5.91" / 150 mm   465.88 ft / 142.00 m   12.47 ft / 3.80 m
   Ends:   0.98" / 25 mm   116.44 ft / 35.49 m   12.47 ft / 3.80 m
     Main Belt covers 123 % of normal length

   - Torpedo Bulkhead - Additional damage containing bulkheads:
      0.98" / 25 mm   465.88 ft / 142.00 m   29.95 ft / 9.13 m
   Beam between torpedo bulkheads 55.77 ft / 17.00 m

   - Hull Bulges:
      0.51" / 13 mm   465.88 ft / 142.00 m   21.33 ft / 6.50 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   6.50" / 165 mm   3.94" / 100 mm      5.91" / 150 mm
   2nd:   1.38" / 35 mm   1.38" / 35 mm      1.38" / 35 mm
   3rd:   0.98" / 25 mm   0.79" / 20 mm      0.98" / 25 mm
   4th:   0.31" / 8 mm         -               -

   - Armoured deck - single deck:
   For and Aft decks: 1.77" / 45 mm
   Forecastle: 1.38" / 35 mm  Quarter deck: 1.77" / 45 mm

   - Conning towers: Forward 5.91" / 150 mm, Aft 1.38" / 35 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 4 shafts, 113,863 shp / 84,942 Kw = 31.00 kts
   Range 9,860nm at 14.00 kts
   Bunker at max displacement = 2,989 tons

Complement:
   785 - 1,021

Cost:
   £4.399 million / $17.598 million

Distribution of weights at normal displacement:
   Armament: 1,258 tons, 6.9 %
      - Guns: 1,258 tons, 6.9 %
   Armour: 4,084 tons, 22.3 %
      - Belts: 1,435 tons, 7.9 %
      - Torpedo bulkhead: 508 tons, 2.8 %
      - Bulges: 188 tons, 1.0 %
      - Armament: 911 tons, 5.0 %
      - Armour Deck: 933 tons, 5.1 %
      - Conning Towers: 109 tons, 0.6 %
   Machinery: 3,806 tons, 20.8 %
   Hull, fittings & equipment: 5,853 tons, 32.0 %
   Fuel, ammunition & stores: 2,577 tons, 14.1 %
   Miscellaneous weights: 699 tons, 3.8 %
      - Hull below water: 239 tons
      - Bulge void weights: 150 tons
      - Hull above water: 41 tons
      - On freeboard deck: 68 tons
      - Above deck: 201 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     21,240 lbs / 9,634 Kg = 57.2 x 9.1 " / 230 mm shells or 3.0 torpedoes
   Stability (Unstable if below 1.00): 1.12
   Metacentric height 3.8 ft / 1.2 m
   Roll period: 16.3 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.63
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has a flush deck,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0.522 / 0.529
   Length to Beam Ratio: 7.72 : 1
   'Natural speed' for length: 24.13 kts
   Power going to wave formation at top speed: 60 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 15.00 degrees
   Stern overhang: -6.56 ft / -2.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   15.00 %,  27.23 ft / 8.30 m,  24.77 ft / 7.55 m
      - Forward deck:   50.00 %,  24.77 ft / 7.55 m,  22.31 ft / 6.80 m
      - Aft deck:   30.00 %,  22.31 ft / 6.80 m,  22.31 ft / 6.80 m
      - Quarter deck:   5.00 %,  22.31 ft / 6.80 m,  23.29 ft / 7.10 m
      - Average freeboard:      23.47 ft / 7.15 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 119.7 %
      - Above water (accommodation/working, high = better): 160.0 %
   Waterplane Area: 28,578 Square feet or 2,655 Square metres
   Displacement factor (Displacement / loading): 111 %
   Structure weight / hull surface area: 139 lbs/sq ft or 678 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.93
      - Longitudinal: 1.89
      - Overall: 1.00
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room

With the size and main battery of armored cruisers ballooning so that they can engage old predreads, there is no room in the budget for so many ships of that size.

There remains a need for a ship capable of long range independent work, and brushing aside conventional cruisers. That ship does not need to be 26000 tons and sporting 8x 345mm.
This ship is designed to bring the size back down to the mission goals.


The Secondary is the heavy 130mm gun, with the side mounts
arranged  with the inner pair superfiring over the wider spaced end pair.
                1      (3)  (5)       7   
               (b)                     (c)
     A (B) [a]                           [d] (X) Y
The 90mm is mounted for all-around fire,
with mounts above the main battery and also superfiring over the 1 and 7 mounts.

Miscellaneous Weight :
Void :
150t : Construction Reserve

AD:
126t : fire control
25t   : LR radio
25t   : Night figthing gear
25t   : Hulesmeyer

OD :
18t : 2TT3 21"
50t : 2x Scout Floatplanes and 1 x Gunpowder Cat

AW :
16t : CO2 Compressor AC
25t :  Additional Fire Suppresion

BW :
178t : Torpedo Nets.
25t : additional pumps
36t : Torpedo reloads

Decks :
6.8 Weather Deck
4.3 Battery Deck
1.8  Armor Deck - 45mm, top of TDS
-0.7  2nd Deck
       -2.0 Bottom main belt
-3.2  1st Deck
-6.9  Engineering
-7.63 Double Bottom

[Jefgte]

...What it was intended to explore is something that
could field the 230L44 gun, with an eye to something
that could reliably engage and sink Jefgte's 191mm cruisers...

Cool, a 15700t Parthian cruiser can sink 6000t Byzantine cruiser.
Compare rather with a 12520t or 15800t Byzantine.
;)
To be pretty sure of winning the superiority must be 30-50%.
Limit yourself to 9000t (vs 6000t).
What could you do with 9000t ?

[Kaiser Kirk]

That is pretty much the problem for the 15,700ts.
Far to expensive for what it can do.
I'd much rather spend 2800 more and field
a Zemaka which can fight anything other than a capital ship.

As for the 9000t - that's what my couple of 8000t & 180mm designs
are for.

Much more efficient use of tonnage.

[Desertfox]

That is one very expensive cruiser. The Japanese Myokos have similar firepower and speed on 6000t less.

[Kaiser Kirk]

That is one very expensive cruiser. The Japanese Myokos have similar firepower and speed on 6000t less.

That's why I concluded that it wouldn't get built.

That particular package of requirements wound up with a ship that was too expensive for one
mission, and not sufficient for another.

Figured I'd share a 'failure'.

[Kaiser Kirk]

I've been tinkering with tenders.

"Sea Frog" or Deniz
Light Tender Design.

2.48 + 9 = 11.5 months to build.
0.31 / HY cost.

Keeping the cost low is part of the design goal.

The Parthians have a number of large support vessels, allowing them to support the majority
of their fleet far far from home.

To support their desire to be able to sustain localized coastal forces they have
been considering light tenders with a shallow draft.

That way they can rebase about their shallow littoral waters and river areas, and support
forces away from the major harbors.

The tenders would need resupply, but trucks -> lighters->tender can provide that,
or coastal vessels can bring it.

The largest vessels expected to need such support would be the 750ton Subs or Torpedo boats, or a squadron of MTBs.

8 x 750 tons = 6000 tons

This would also support a swarm of MTBs, or subs,   or a pair of frigates or even most Parthian cruisers.

The stern is sloped to be slightly awash, to allow aircraft or MTBs to be winched on board.  A roller path and winch allows them to be brought into the hanger / maintenance bay area.

A lightly built hanger structure fills the aft deck, arched for lighter construction, and so wind
will not push the vessel sideways.

The hanger is 5m tall, spanning from 1.4m to 6.4m.

Armanent : 2624 * 0.02 = 52.48 vs. 45 carried.
Casements on the ships side at weather deck level preserve the interior space.
batteries of 4 light guns bear on either beam, with the hopes of defense against
a maurading solo gunboat or coastal DD.

A pair of 57mm AA is mounted on each side, again aimed at warding off light air attack.

GAST 15mm are mounted for both strafing defense and boarders.

The ultimate defense is few vessels have a 3m draft, and the tender will scuttle somewhere else.



Deniz   Ghoorbagheh, Parthian Light Tender laid down 1922

Displacement:
   2,480 t light; 2,559 t standard; 2,624 t normal; 2,676 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (260.00 ft / 255.91 ft) x 57.41 ft x (9.84 / 10.01 ft)
   (79.25 m / 78.00 m) x 17.50 m  x (3.00 / 3.05 m)

Armament:
      8 - 3.54" / 90.0 mm 50.0 cal guns - 24.25lbs / 11.00kg shells, 200 per gun
     Quick firing guns in casemate mounts, 1911 Model
     8 x Single mounts on sides, evenly spread
      4 - 2.24" / 57.0 mm 60.0 cal guns - 6.61lbs / 3.00kg shells, 300 per gun
     Breech loading guns in deck mounts, 1917 Model
     2 x 2-gun mounts on sides amidships
      2 raised mounts
      8 - 0.59" / 15.0 mm 70.0 cal guns - 0.11lbs / 0.05kg shells, 1,500 per gun
     Breech loading guns in deck mounts, 1918 Model
     4 x Twin mounts on side ends, evenly spread
      4 double raised mounts
      Weight of broadside 221 lbs / 100 kg

Machinery:
   Coal and oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 1,327 shp / 990 Kw = 12.00 kts
   Range 3,172nm at 8.00 kts
   Bunker at max displacement = 117 tons (23% coal)

Complement:
   183 - 238

Cost:
   £0.288 million / $1.151 million

Distribution of weights at normal displacement:
   Armament: 45 tons, 1.7 %
      - Guns: 45 tons, 1.7 %
   Machinery: 46 tons, 1.8 %
   Hull, fittings & equipment: 868 tons, 33.1 %
   Fuel, ammunition & stores: 144 tons, 5.5 %
   Miscellaneous weights: 1,521 tons, 58.0 %
      - Hull below water: 515 tons
      - Hull void weights: 20 tons
      - Hull above water: 688 tons
      - On freeboard deck: 230 tons
      - Above deck: 68 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     8,239 lbs / 3,737 Kg = 370.4 x 3.5 " / 90 mm shells or 2.0 torpedoes
   Stability (Unstable if below 1.00): 1.53
   Metacentric height 4.5 ft / 1.4 m
   Roll period: 11.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 100 %
         - Recoil effect (Restricted arc if above 1.00): 0.05
   Seaboat quality  (Average = 1.00): 2.00

Hull form characteristics:
   Hull has rise aft of midbreak, low quarterdeck ,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.635 / 0.637
   Length to Beam Ratio: 4.46 : 1
   'Natural speed' for length: 16.00 kts
   Power going to wave formation at top speed: 37 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 13.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  17.72 ft / 5.40 m,  15.26 ft / 4.65 m
      - Forward deck:   35.00 %,  15.26 ft / 4.65 m,  12.80 ft / 3.90 m
      - Aft deck:   35.00 %,  21.00 ft / 6.40 m,  21.00 ft / 6.40 m
      - Quarter deck:   10.00 %,  4.59 ft / 1.40 m,  -1.08 ft / -0.33 m
      - Average freeboard:      15.68 ft / 4.78 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 61.4 %
      - Above water (accommodation/working, high = better): 202.3 %
   Waterplane Area: 11,101 Square feet or 1,031 Square metres
   Displacement factor (Displacement / loading): 152 %
   Structure weight / hull surface area: 61 lbs/sq ft or 300 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.89
      - Longitudinal: 2.89
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Warning: Beam between bulkheads too wide


Miscellaneous Weight

Reserve : 20t

AD
5t  FC : The vessel needs to be able to ward off a enemy patrol craft, sub or aircraft.
23t : A 30m high cage mast is the lightest spotting top, and gives best sight lines. Tonnage from USS Texas. Also Air Control platform.
25t : LR Radio  - Communciations for the lighter vessels
10t : Dedicated SR radio band for Aircraft.


OD :
20t - Plot Room
80t - 4x Scout Floatplanes.
10t - 2x Gunpowder CAT (each beam)
120t - Aft Hanger /  On-deck space to work MTBs under cover.
           Conceptually, this is, shown by the raised aft deck, while the stern dives down to form the ramp.


HAW :
3t - Compressor CO2 A/C
40t - Additional Berthing 
20t - Surgical Wardroom
25t - Additional fire Suppression
600t - Fleet Support

HBW:
240t : Torpedo/ Mine / Depth Charge storage
60t :   Ammunition Storage
200t : Fuel Storage Tanks, double wall
15t : Enhanced Hydrophone station.


Decks :
3.9m    Weather Deck
1.4m    Strength deck, hanger deck
-2.4m   Engineering, stores
-2.9m  0.5m double bottom.

[TacCovert4]

With the high fuel consumption of smaller ships doing combat ops, I think you should shift more tonnage to fuel.  I'd say that of your 800t of supply spaces, I'd go with 500t fuel and 300t supplies.

[Kaiser Kirk]

On the one hand correct on the other...a conceptual problem.

Conceptually... Snip wanted to make it simple and have players only
be required to engage on core naval warfare aspects.
So he didn't want mercantile ships at all - any resupply vessels, transports....tankers
were to be handwaved.

I really thought specific tenders were needed to answer questions about being
able to project force.

So we wound up with an Auxiliary rule focused , and the handwaving of most non-tenders.

End result : I could very reasonably get by with just the Fleet Supply Tonnage.
I think I should have enough there to 'restock'.  Hence the tonnage for reloads.

BUT...its not a tanker, the fuel is there to 'top off' whatever is there with non-bunker fuel.
The main fuel source is supposed to be handwaved.  There's a fuel barge...or something.

200 tons, is 448000 lbs of fuel, or 74,666 gallons. The fall down for the skin of a 5000 gal tank isn't very large, I figured it out and forgot. Like 10% of weight.
So call it 180 tons / 65,000 gallons.
Just enough to 'top off' a sub/DD, or fill a MTB swarm.

What would be a reasonable number?
Pretty high.
My 1899 steam torpedo boats had 4 tons of fuel.
My Javelin early DDs/ Torpedo boats have 61 tons of fuel.
My Seahawk 750t DDs had 145 tons

so x 8 would be 1160... that's alot.


What if we did have tankers ?

Personally, I am severely tempted to make aux 'tankers' by having very large fuel tanks instead of misc weight.
The only place it would come into play is if I wanted fast tankers.

We could make a rule !

The problem is...no one will want to track fuel consumption of their vessels.
So it will be an eyeball of tanker capacity.
Or...handwaving.

Then tack on that when considering the starting IC/BP point,
only warship construction was really forecast- Land/DP/Air/Fort units
and widespread aux construction wasn't really envisioned.
Adding another " you need" aux category then saps from the budgets.

[TacCovert4]

Yeah. I vote against an additional rule.  I was mostly thinking that 200t doesn't sustain mtbs for very long independent of other supplies,  and 600t keeps them sustained a long time in food and torpedoes. 

[Kaiser Kirk]

It's a good question to ponder overall.

Right now,  the core is the 600 tons fleet support.

The 'Fluff' becomes the
240 tons torp/mine/dc storage and 60 tons ammo mag
and 200 tons fuel tanks.

I could dump those and either add 500tons fleet support
and just point to then 1100 tons as

or make it 500 tons fuel.

I dunno,
Seems "better" to me to have the top-off tonnage
even if I don't *have* to have it.

[Kaiser Kirk]

So I pushed the tonnage up to 2800,
which works out nicely to 0.35/HY for 2 HY.

Doubled the fuel allocation to 400 tons.
Still not 600, but a great deal closer.

That still is nowhere enough to refuel a destroyer flotilla,
that's what the hand-waved fuel barge is for....

But from a storyline concept, it does 'feel' better.

Deniz   Ghoorbagheh, Parthian Light Tender laid down 1922

Displacement:
   2,800 t light; 2,886 t standard; 2,962 t normal; 3,023 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (260.00 ft / 255.91 ft) x 63.98 ft x (9.84 / 10.01 ft)
   (79.25 m / 78.00 m) x 19.50 m  x (3.00 / 3.05 m)

Armament:
      8 - 3.54" / 90.0 mm 50.0 cal guns - 24.25lbs / 11.00kg shells, 200 per gun
     Quick firing guns in casemate mounts, 1911 Model
     8 x Single mounts on sides, evenly spread
      4 - 2.24" / 57.0 mm 60.0 cal guns - 6.61lbs / 3.00kg shells, 300 per gun
     Breech loading guns in deck mounts, 1917 Model
     2 x 2-gun mounts on sides amidships
      2 raised mounts
      8 - 0.59" / 15.0 mm 70.0 cal guns - 0.11lbs / 0.05kg shells, 1,500 per gun
     Breech loading guns in deck mounts, 1918 Model
     4 x Twin mounts on side ends, evenly spread
      4 double raised mounts
      Weight of broadside 221 lbs / 100 kg

Machinery:
   Coal and oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 1,466 shp / 1,093 Kw = 12.00 kts
   Range 3,400nm at 8.00 kts
   Bunker at max displacement = 136 tons (23% coal)

Complement:
   199 - 260

Cost:
   £0.320 million / $1.281 million

Distribution of weights at normal displacement:
   Armament: 45 tons, 1.5 %
      - Guns: 45 tons, 1.5 %
   Machinery: 51 tons, 1.7 %
   Hull, fittings & equipment: 984 tons, 33.2 %
   Fuel, ammunition & stores: 162 tons, 5.5 %
   Miscellaneous weights: 1,721 tons, 58.1 %
      - Hull below water: 715 tons
      - Hull void weights: 20 tons
      - Hull above water: 688 tons
      - On freeboard deck: 230 tons
      - Above deck: 68 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     9,627 lbs / 4,367 Kg = 432.8 x 3.5 " / 90 mm shells or 2.2 torpedoes
   Stability (Unstable if below 1.00): 1.72
   Metacentric height 6.2 ft / 1.9 m
   Roll period: 10.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 100 %
         - Recoil effect (Restricted arc if above 1.00): 0.03
   Seaboat quality  (Average = 1.00): 2.00

Hull form characteristics:
   Hull has rise aft of midbreak, low quarterdeck ,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.643 / 0.645
   Length to Beam Ratio: 4.00 : 1
   'Natural speed' for length: 16.00 kts
   Power going to wave formation at top speed: 38 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 13.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  17.72 ft / 5.40 m,  15.26 ft / 4.65 m
      - Forward deck:   35.00 %,  15.26 ft / 4.65 m,  12.80 ft / 3.90 m
      - Aft deck:   35.00 %,  21.00 ft / 6.40 m,  21.00 ft / 6.40 m
      - Quarter deck:   10.00 %,  4.59 ft / 1.40 m,  -1.08 ft / -0.33 m
      - Average freeboard:      15.68 ft / 4.78 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 62.3 %
      - Above water (accommodation/working, high = better): 208.9 %
   Waterplane Area: 12,465 Square feet or 1,158 Square metres
   Displacement factor (Displacement / loading): 153 %
   Structure weight / hull surface area: 64 lbs/sq ft or 314 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.88
      - Longitudinal: 2.89
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Warning: Beam between bulkheads too wide

"Sea Frog" or Deniz
Light Tender Design.

2.8 + 9 = 11.8 months to build.
0.35 / HY cost.

The Parthians have a number of large support vessels, allowing them to support the majority
of their fleet far far from home.

To support their desire to be able to sustain localized coastal forces they have
been considering light tenders with a shallow draft.

The tenders would need resupply, but trucks -> lighters->tender can provide that,
or coastal vessels can bring it.

The largest vessels expected to need such support would be the 750ton Subs or Torpedo boats, or a squadron of MTBs.

8 x 750 tons = 6000 tons

This would also support a swarm of MTBs, or subs,   or a pair of frigates or even most Parthian cruisers.

The stern is sloped to be slightly awash, to allow aircraft or MTBs to be winched on board.  A roller path and winch allows them to be brought into the hanger / maintenance bay area.

A lightly built hanger structure fills the aft deck, arched for lighter construction, and so wind
will not push the vessel sideways.

The hanger is 5m tall, spanning from 1.4m to 6.4m.

Armanent : 2624 * 0.02 = 52.48 vs. 45 carried.
Casements on the ships side at weather deck level preserve the interior space.
batteries of 4 light guns bear on either beam, with the hopes of defense against
a maurading solo gunboat or coastal DD.

A pair of 57mm AA is mounted on each side, again aimed at warding off light air attack.

GAST 15mm are mounted for both strafing defense and boarders.

The ultimate defense is few vessels have a 3m draft, and the tender will scuttle somewhere else.


Miscellaneous Weight

Reserve : 20t

AD
5t  FC : The vessel needs to be able to ward off a enemy patrol craft, sub or aircraft.
23t : A 30m high cage mast is the lightest spotting top, and gives best sight lines. Tonnage from USS Texas. Also Air Control platform.
25t : LR Radio  - Communciations for the lighter vessels
10t : Dedicated SR radio band for Aircraft.


OD :
20t - Plot Room
80t - 4x Scout Floatplanes.
10t - 2x Gunpowder CAT (each beam)
120t - Aft Hanger /  On-deck space to work MTBs under cover.
           Conceptually, this is, shown by the raised aft deck, while the stern dives down to form the ramp.


HAW :
3t - Compressor CO2 A/C
40t - Additional Berthing 
20t - Surgical Wardroom
25t - Additional fire Suppression
600t - Fleet Support

HBW:
240t : Torpedo/ Mine / Depth Charge storage
60t :   Ammunition Storage
400t : Fuel Storage Tanks, double wall
15t : Enhanced Hydrophone station.


Decks :
3.9m    Weather Deck
1.4m    Strength deck, hanger deck
-2.4m   Engineering, stores
-2.9m  0.5m double bottom.

[Kaiser Kirk]

yet another tender.

Question for the peanut gallery - I'm providing for ASW mines on harbor netting.
It was done historically, and was far more useful than pure nets.

But at what point does one cross into 'weapon' category there - they could hurt a sub
So I'm really not sure that's a valid Aux role, but it is so far from an offensive weapon that I am unsure
where to draw that line. So I'm flipping back on forth on if I should or should not include the little mines.

Without them...I'd have 1% more netting. So not a dealbreaker.


The Parthians have not built out the harbor defenses in territorial areas,
first focusing on basic maintenance infrastructure, so a wounded ship does not have to sail 8000nm to get repaired.

Further, they hope to use their fleet train to set up in non-developed
bays and anchorages for temporary bases.

A net-tending vessel - primarily to provide portable ASW/anti-torpedo netting for anchorages, but also equipped for a small floatplane group to provide local reconnaisance.

The stern ramps down, intended to allow floatplanes to advance onto a wire mesh mat and then be winched up the fantail.

The gunpowder catapults fire directly over the bow.
The vessel also carries only small group of on-board planes.
These are both an experiment, and to try to keep enemy reconnaisance at bay

Anchorage Torpedo nets are carried, these are double weight Bullivant nets, 50kg per square meters. Small 50kg electro-contact mines are studded into each 10x10m section, or +1kt/sq. meter. These are remotely armed and disarmed via electrical pulses.

Each 10m x 10m section is 5050kg = 11,110lbs = 4.96 naval tons.
To carry that the float must displace as much or more in seawater volume.
1 cu meter of seawater weighs 1,024 kg....so 5 cu meters would > the net
110m...which.....ah lets call the floats 0.6tons, so it's 10m for 5.6tons.

For this case, they want to be able to deploy them in panels either
20m deep.

So 3.0km is 300 x 20m sections or 3360t

Overall, this allows 2.0km of netting, which should mean the vessel can secure and anchorage and landing area.  If kept to the shallows the netting should extend to the bottom. Otherwise they can be placed close to ships so that there is no room for a sub to sneak under, rise and fire.

A pair of 100t launches are carried to serve as nettenders.
Deniz - Sea
Saraydar - Custodian

3 HY to build, aux so 1/4 price, so want tonnage in multiples of 12.
6.6 / 12 = 0.55/HY.

Deniz Saraydar, Parthia Harbormaster NetTender laid down 1922

Displacement:
   6,599 t light; 6,838 t standard; 7,558 t normal; 8,134 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (334.45 ft / 328.08 ft) x 72.18 ft x (16.40 / 17.48 ft)
   (101.94 m / 100.00 m) x 22.00 m  x (5.00 / 5.33 m)

Armament:
      8 - 5.12" / 130 mm 50.0 cal guns - 70.55lbs / 32.00kg shells, 200 per gun
     Quick firing guns in casemate mounts, 1922 Model
     8 x Single mounts on sides, evenly spread
      8 hull mounts in casemates- Limited use in any sea
      6 - 3.54" / 90.0 mm 50.0 cal guns - 24.25lbs / 11.00kg shells, 200 per gun
     Anti-air guns in deck mounts, 1922 Model
     2 x Single mounts on centreline ends, evenly spread
     4 x Single mounts on side ends, evenly spread
      8 - 2.24" / 57.0 mm 45.0 cal guns - 6.61lbs / 3.00kg shells, 300 per gun
     Breech loading guns in deck mounts, 1922 Model
     2 x Twin mounts on sides amidships
      2 raised mounts
     2 x Twin mounts on centreline ends, evenly spread
      2 raised mounts
      Weight of broadside 763 lbs / 346 kg

Machinery:
   Coal and oil fired boilers, steam turbines,
   Electric motors, 3 shafts, 6,865 shp / 5,121 Kw = 16.00 kts
   Range 8,800nm at 12.00 kts
   Bunker at max displacement = 1,296 tons (23% coal)

Complement:
   404 - 526

Cost:
   £0.830 million / $3.321 million

Distribution of weights at normal displacement:
   Armament: 146 tons, 1.9 %
      - Guns: 146 tons, 1.9 %
   Machinery: 238 tons, 3.1 %
   Hull, fittings & equipment: 1,627 tons, 21.5 %
   Fuel, ammunition & stores: 959 tons, 12.7 %
   Miscellaneous weights: 4,589 tons, 60.7 %
      - Hull below water: 3,475 tons
      - Hull void weights: 60 tons
      - Hull above water: 380 tons
      - On freeboard deck: 580 tons
      - Above deck: 94 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     15,025 lbs / 6,815 Kg = 224.1 x 5.1 " / 130 mm shells or 2.4 torpedoes
   Stability (Unstable if below 1.00): 2.46
   Metacentric height 12.0 ft / 3.7 m
   Roll period: 8.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 51 %
         - Recoil effect (Restricted arc if above 1.00): 0.01
   Seaboat quality  (Average = 1.00): 1.63

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a round stern
   Block coefficient (normal/deep): 0.681 / 0.688
   Length to Beam Ratio: 4.55 : 1
   'Natural speed' for length: 18.11 kts
   Power going to wave formation at top speed: 49 %
   Trim (Max stability = 0, Max steadiness = 100): 31
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 3.28 ft / 1.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  17.49 ft / 5.33 m,  14.30 ft / 4.36 m
      - Forward deck:   25.00 %,  14.30 ft / 4.36 m,  11.12 ft / 3.39 m
      - Aft deck:   35.00 %,  11.12 ft / 3.39 m,  11.12 ft / 3.39 m
      - Quarter deck:   20.00 %,  11.12 ft / 3.39 m,  11.12 ft / 3.39 m
      - Average freeboard:      12.41 ft / 3.78 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 72.0 %
      - Above water (accommodation/working, high = better): 103.7 %
   Waterplane Area: 18,660 Square feet or 1,734 Square metres
   Displacement factor (Displacement / loading): 139 %
   Structure weight / hull surface area: 74 lbs/sq ft or 362 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.95
      - Longitudinal: 1.50
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Adequate accommodation and workspace room
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather



Armanent is casement mounted 130mm for surface raiders, expected to be fast and high speed, and a heavy suite of AA to fend off enemy air.


"Armanent": 2% of Normal = 7558 * 0.02 = 151.16
Guns : 146
ok !



Miscellaneous Wieght :
60t reserve

AD:
11t Fire Control 1918
25t LR Fire Control
10t SR Radio - Dedicated Flight Command
25t Hulesmeyer
23t Cage Mast for Air Traffic Control

OD:
120 : 6x  20  Scout  Float Plane
10t : 2x waist gun powder cats .
25 : Harbor Command Plotting room....
400 : 2x100t "Nettender" tug
25t : Additional Firefighting gear

HAW
25t Compressor CO2 AC
25t Minesweeping gear
15t  CO2 Compressor AC
25t  Additional Fire Suppression
200t : Additional Berthing
100t : Hospital Ward

HBW
3360t - Bueliviant Torpedo netting + ASW mines and floats. 3000m x 20m
60 :     Additional stores & avgas for floatplanes
25t :    Additional pumps
30t :  2x Enhanced Hydrophone stations

[TacCovert4]

I'm going to say that a net with mines is purely defensive and therefore wouldn't qualify as a weapon.  It's a reactive protection system,  it cannot be used offensively. 

[The Rock Doctor]

*USS Enterprise encounters The Parthian Web.*

But yeah, it's probably fine for me.