Parthian vessels 1916 onwards

[Kaiser Kirk]

Do you have the 1920 cruiser tech?  That tech really helps sloops and mine warfare vessels.  Since anything built to that tech that's small only needs to be .75 comp you get a lot of leeway for misc weight.  Not like a 500 ton ship is going to survive in a firefight whether it's got .5, .75 or 1.0 hull strength.....so might as well build it a tad lighter and get the ASW and AA on it.

Yes I do, and that will probably be the basis of open ocean escort types, so I can make DE-style vessels.
I have some ~1000 ton multi-role escort designs
that I'd like to build in lots of 3 or 4.  That would allow triangulation around subs, as well as
stand off escort distance on all sides.

Figuring out how to pay for those is an entirely different problem
Jefgte's suggestion to rearm and re-task old destroyers seems promising.
But I'd rather build new, and keep DDs as Torpedo boats or fleet escorts

So I lean towards AUX to fill the escort/patrol role.
What I really want is 500 ton Aux-builds so I can simply lay down a hull every 6 months,
but with the minimum armament of 1 x 75mm + gun, some AA, and then the ASW loadout, the minimum "normal" displacement gets pushed up.
The build cost between the smaller and heavier versions is only 22 tons/hy/ship, which is not prohibitive....but that is a 29% creep...but 0.022bp/ship...but creep...

[Kaiser Kirk]

The current Parthian destroyers are the 1143 'Wolf' Fleet destroyer and 'Leopard' Corvette (aka Pacific Destroyer).
This is meant to be the 'Wolf mkII' , while the 'Leopard II' is delayed waiting for the 118mm ASW howitzer to finish developement

New geared turbines allow better range, the addition of
sonar allows the ships to be more effective ASW role.

Vakharz "Wolf" , Parthian Empire Fleet Destroyer laid down 1924

Displacement:
   1,140 t light; 1,201 t standard; 1,380 t normal; 1,523 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (339.13 ft / 334.65 ft) x 31.99 ft x (10.93 / 11.72 ft)
   (103.37 m / 102.00 m) x 9.75 m  x (3.33 / 3.57 m)

Armament:
      4 - 4.72" / 120 mm 43.0 cal guns - 55.12lbs / 25.00kg shells, 200 per gun
     Quick firing guns in deck mounts, 1924 Model
     4 x Single mounts on centreline ends, evenly spread
      2 raised mounts - superfiring
      4 - 2.24" / 57.0 mm 60.0 cal guns - 6.61lbs / 3.00kg shells, 500 per gun
     Anti-air guns in deck mounts, 1924 Model
     2 x 2-gun mounts on sides, forward deck aft
      2 raised mounts
      8 - 0.59" / 15.0 mm 70.0 cal guns - 0.11lbs / 0.05kg shells, 3,000 per gun
     Breech loading guns in deck mounts, 1924 Model
     4 x Twin mounts on side ends, evenly spread
      4 raised mounts
      Weight of broadside 248 lbs / 112 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.24" / 6 mm         -               -
   2nd:   0.24" / 6 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 1 shaft, 27,010 shp / 20,150 Kw = 31.10 kts
   Range 5,000nm at 14.00 kts
   Bunker at max displacement = 322 tons

Complement:
   113 - 147

Cost:
   £0.456 million / $1.825 million

Distribution of weights at normal displacement:
   Armament: 42 tons, 3.0 %
      - Guns: 42 tons, 3.0 %
   Armour: 3 tons, 0.2 %
      - Armament: 3 tons, 0.2 %
   Machinery: 687 tons, 49.8 %
   Hull, fittings & equipment: 329 tons, 23.8 %
   Fuel, ammunition & stores: 240 tons, 17.4 %
   Miscellaneous weights: 79 tons, 5.7 %
      - Hull below water: 25 tons
      - Hull void weights: 13 tons
      - Hull above water: 1 tons
      - On freeboard deck: 31 tons
      - Above deck: 9 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     402 lbs / 182 Kg = 7.6 x 4.7 " / 120 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.49
   Metacentric height 1.8 ft / 0.5 m
   Roll period: 10.0 seconds
   Steadiness   - As gun platform (Average = 50 %): 51 %
         - Recoil effect (Restricted arc if above 1.00): 0.24
   Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
   Hull has a flush deck,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0.413 / 0.425
   Length to Beam Ratio: 10.46 : 1
   'Natural speed' for length: 18.29 kts
   Power going to wave formation at top speed: 64 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 15.00 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 %,  16.73 ft / 5.10 m,  14.27 ft / 4.35 m
      - Forward deck:   20.00 %,  14.27 ft / 4.35 m,  11.81 ft / 3.60 m
      - Aft deck:   45.00 %,  11.81 ft / 3.60 m,  11.81 ft / 3.60 m
      - Quarter deck:   15.00 %,  11.81 ft / 3.60 m,  11.81 ft / 3.60 m
      - Average freeboard:      12.75 ft / 3.89 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 172.4 %
      - Above water (accommodation/working, high = better): 129.3 %
   Waterplane Area: 6,291 Square feet or 584 Square metres
   Displacement factor (Displacement / loading): 70 %
   Structure weight / hull surface area: 29 lbs/sq ft or 144 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.33
      - Overall: 0.55
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room

Warning: Beam between bulkheads too wide



Intended as a Fleet destroyer for use outside the Oceania theater.

Range to reach a base and return at fleet speeds

The 120mm is a good destroyer
gun with decent offensive punch.

The 57mm guns are mounted 'en echelon' amid ships, on a lozenge shaped elevated platform. These replace the 90mms of the earlier series.

The TDC is in the column holding up the platform and the torpedoes
are immediately fore and aft of that.

Basic Sonar + Enhanced Hydrophones for an ASW role

                     (1)                                       DC
A(B)          TT        TT       'Y'   (X) Y
                          (2)                                 DC

Range @ Speeds :

Trial Speed is 31.94knts

322t max bunker is 5000 @ 14kts

2200nm at 10knots : 77t to "get home"
So 245t are available for offensive operations,
more if "home" is close.

90% power is ~30.33kts.
50% power is ~26kts

245t fuel is good for :
445nm @ 30.33knts = 14.6 hrs.
718nm @ 26 knots = 27.6 hrs
2720nm @ 16knots = 170 hrs / 7  days

The Geared engines give an
additional reserve via better fuel efficiency
but are very new and not worked into
the calculations yet,
they meant the true range is 5500@ 14kts

With the fleet at 12-14knots,
14 or 16 knots allows reasonable range when working with the fleet from bases.


Misc wt :
14t     Reserve Wt.

4 FC
0  SR Radio
5 NF


18t   2TT3 21"

2t    Lt. MS paravane
8t     DC
2t     "Y" DC Thrower
1t     ASW Paravane

1t     CO2 A/C




15t   Enhanced Hydrophone package
10t  Basic Sonar

[Kaiser Kirk]

Do you have the 1920 cruiser tech?  That tech really helps sloops and mine warfare vessels.  Since anything built to that tech that's small only needs to be .75 comp you get a lot of leeway for misc weight.  Not like a 500 ton ship is going to survive in a firefight whether it's got .5, .75 or 1.0 hull strength.....so might as well build it a tad lighter and get the ASW and AA on it.

Exploring Tac's comment further, I tried taking the 600 ton PS-2 AUX and seeing how small I could make it on 0.75.

Slimming it down to lower the tonnage boosted the Seakeeping.
So I chopped the end off and got it to 50m.
Then I played with BC and adjusted the Turbgenerator weight...
and got the final result to 460 tons for the same vessel but cruiser built.
At 500 tons there's room for more misc weight and so the more DCs

That would be quite decent for a wartime build as I could
build them at 6months/ dock.
....so I'll remember that build.

However what I need is lots and lots of light platforms
to both patrol in peace time, and allow proper ASW screens.
So # of hulls for cost matters .
at 500/ship vs 150 - 174/ship, the Aux pencils out well.

Then there's the combat power of the 'cruiser' vs Aux.

From Springstyle notes, Aux have 1/4 "hit points" and crew,
they won't do Damage Control like a Cruiser build..

but a 460ton cruiser, with no armor and 492 float...and 1x90mm gun...
should not go destroyer hunting.

Worth exploring though.

[The Rock Doctor]

I'd forgotten about the appearance of sonar and will have to factor it into construction in 2/24...

[Kaiser Kirk]

I'd forgotten about the appearance of sonar and will have to factor it into construction in 2/24...

You could just double down on ASW harpoons instead !

Basic sonar is a limited tool, the Hydrophones due most of the work,
but would allow attacks to be prosecuted better.

Against old and small subs, that's not as much an issue,
but against bigger and newer subs, the bigger DCs and better
target finding of Sonar should help.

[TacCovert4]

Yeah, against small shallow subs that can't maneuver, you can just locate, rush, drop.  Against subs that have actual ability to evade underwater, you need the larger charges and the better sensors to make sure you catch their dodge attempt.

[Kaiser Kirk]

Anyhow,
this is more what I was eyeing for 'Coastal Gunboats' ...or even DEs,
like 20-40 of them...
but turns out that I don't have 80BP / HY, so I may build a handful
to serve as just coastal gunboats and replace the old Dolphin class
but for DE roles... I need to find something else to build.

Sibari, Parthian Coastal Gunboat laid down 1924

Displacement:
   2,000 t light; 2,189 t standard; 2,277 t normal; 2,347 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (250.72 ft / 246.06 ft) x 50.85 ft x (9.84 / 10.10 ft)
   (76.42 m / 75.00 m) x 15.50 m  x (3.00 / 3.08 m)

Armament:
      4 - 6.50" / 165 mm 43.0 cal guns - 143.30lbs / 65.00kg shells, 240 per gun
     Quick firing guns in deck and hoist mounts, 1924 Model
     2 x 2-gun mounts on centreline ends, evenly spread
      2 - 6.42" / 163 mm 21.0 cal guns - 158.73lbs / 72.00kg shells, 200 per gun
     Quick firing  guns in deck and hoist mount, 1924 Model
     1 x 2-gun mount on centreline, forward deck centre
      1 raised mount
      8 - 2.24" / 57.0 mm 60.0 cal guns - 6.61lbs / 3.00kg shells, 900 per gun
     Anti-air guns in deck and hoist mounts, 1924 Model
     2 x 2-gun mounts on sides amidships
      2 raised mounts
     2 x 2-gun mounts on centreline ends, evenly spread
      2 double raised mounts
      16 - 0.59" / 15.0 mm 70.0 cal guns - 0.11lbs / 0.05kg shells, 5,000 per gun
     Machine guns in deck mounts, 1924 Model
     4 x 2 row quad mounts on side ends, evenly spread
      4 double raised mounts
      Weight of broadside 945 lbs / 429 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.94" / 100 mm   123.03 ft / 37.50 m   8.53 ft / 2.60 m
   Ends:   Unarmoured
     Main Belt covers 77 % of normal length

   - 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:   4.72" / 120 mm   2.56" / 65 mm      3.94" / 100 mm
   2nd:   2.56" / 65 mm   1.38" / 35 mm      1.38" / 35 mm
   3rd:   0.59" / 15 mm   0.12" / 3 mm            -
   4th:   0.59" / 15 mm         -               -

   - Armoured deck - single deck:
   For and Aft decks: 1.57" / 40 mm
   Forecastle: 1.57" / 40 mm  Quarter deck: 1.57" / 40 mm

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

Machinery:
   Coal and oil fired boilers, steam turbines,
   Electric motors, 2 shafts, 5,960 shp / 4,446 Kw = 18.10 kts
   Range 3,140nm at 10.00 kts
   Bunker at max displacement = 159 tons (23% coal)

Complement:
   164 - 214

Cost:
   £0.508 million / $2.033 million

Distribution of weights at normal displacement:
   Armament: 187 tons, 8.2 %
      - Guns: 187 tons, 8.2 %
   Armour: 580 tons, 25.5 %
      - Belts: 207 tons, 9.1 %
      - Armament: 78 tons, 3.4 %
      - Armour Deck: 280 tons, 12.3 %
      - Conning Tower: 15 tons, 0.6 %
   Machinery: 200 tons, 8.8 %
   Hull, fittings & equipment: 716 tons, 31.4 %
   Fuel, ammunition & stores: 277 tons, 12.2 %
   Miscellaneous weights: 317 tons, 13.9 %
      - Hull below water: 129 tons
      - Hull void weights: 15 tons
      - Hull above water: 34 tons
      - On freeboard deck: 50 tons
      - Above deck: 89 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     3,646 lbs / 1,654 Kg = 26.6 x 6.5 " / 165 mm shells or 1.4 torpedoes
   Stability (Unstable if below 1.00): 1.30
   Metacentric height 2.9 ft / 0.9 m
   Roll period: 12.5 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.47
   Seaboat quality  (Average = 1.00): 1.10

Hull form characteristics:
   Hull has a flush deck,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0.647 / 0.650
   Length to Beam Ratio: 4.84 : 1
   'Natural speed' for length: 15.69 kts
   Power going to wave formation at top speed: 60 %
   Trim (Max stability = 0, Max steadiness = 100): 63
   Bow angle (Positive = bow angles forward): 15.00 degrees
   Stern overhang: -3.28 ft / -1.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   25.00 %,  17.39 ft / 5.30 m,  14.93 ft / 4.55 m
      - Forward deck:   25.00 %,  14.93 ft / 4.55 m,  12.47 ft / 3.80 m
      - Aft deck:   25.00 %,  12.47 ft / 3.80 m,  12.47 ft / 3.80 m
      - Quarter deck:   25.00 %,  12.47 ft / 3.80 m,  12.47 ft / 3.80 m
      - Average freeboard:      13.64 ft / 4.16 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 68.2 %
      - Above water (accommodation/working, high = better): 145.2 %
   Waterplane Area: 9,559 Square feet or 888 Square metres
   Displacement factor (Displacement / loading): 118 %
   Structure weight / hull surface area: 65 lbs/sq ft or 316 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.65
      - Longitudinal: 2.49
      - Overall: 0.75
   Caution: Hull subject to strain in open-sea
   Excellent machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

Warning: Beam between bulkheads too wide


Guns :
165mm are primary direct fire.
163mm HOW are bombardment or ASW
57mm are primary AA sited for 6 Fore/aft/beam
Paired GAST 15mm are anti-strafing.

Borrowed from submarines are 4 bow tubes
firing 21" torpedoes


Armor :
Armored Deck at 1.3m caps Belt
Belt extends from 1.3m to -1.3m
Bow and Stern are protective decks.

TDS :
The ship has no TDS,
relying on it's small size, high manueverability via electric drive, and really shallow draft.

Engines:
25% Oil-sprayed Coal, or wood.
75% Oil-fired Steam

0.1 knot indicates aux diesel


Reserve : 15t

AD :
19t FC
25t NF - Aft Con searchlight tower, etc.
0t SR Radio
10t SR Radio for Spotting
25t Hulesmeyer
10t Squadron Plot Room

OD
5t paravanes
20t - Scout Floatplane in "Q"
5t - Gunpowder catapult
2t "Y" DC throwers
8t  DC
10t - Mine rails


HAW
2t -    CO2 Compressor AC
32t-   Marine Section

HBW

24t - 4 bow torpedo tubes,  4 torpedoes 21" x 3t
15t - Enhanced Hydrophone
10t - Sonar
50t - Turbogenerators

[TacCovert4]

I mean the speed says corvette, but the armor and guns say 'I can take on some light cruisers'.  Pretty stout for a 'DE'.

[Jefgte]

AGB for Parthian.
Coastal Colonial Cruiser a little too slow for Byzantium.
Byzantium need 24kts min.
However, a good ship & a good harbor defender.

;)

[The Rock Doctor]

I'd forgotten about the appearance of sonar and will have to factor it into construction in 2/24...

You could just double down on ASW harpoons instead !

It's not a bad idea at all.  My guys can practice on whales during peacetime.

[Desertfox]

Solid gunboat, slow but good punch. Similar to the Japanese Surabayas, which proved quite handy recently.

[Kaiser Kirk]

I've been looking at gunboats for a while, and have a broad range of designs.

That one just meets the criteria well, and should be a very very good fire support vessel.

165mm direct fire, and 163mm HOW combined with spotters on the ground or air
should be a very effective mix for any rebels or small unit battles.

The type of scenario Rocky's writing about, hunting River pirates - also would be great for.

Anyhow, one of the fun part of design comments is the challenge to explore fixing deficiencies.
Jefgte noted the low speed precludes working with the battleline. For him 24knts. for me 23knts.
I have some other 23/26/28 knot gunboats, but not with this Misc Wt and gun layout.

So I worked the ship to see what it "costs" to have that 'close escort' capability
while keeping everything else or improving it.

50% more tonnage.
Maybe 51-52%, as I had to scrape the design down.

Still, I added another 2-gun 165mm mounting....

...But lost the very shallow draft.
Which bums me out. Wanted ~10feet for rivers, plus
standard Torpedo settings were more 3.5-4m + , to avoid wave troughs and broaching while still less than cruiser hulls.
...still can't (generally) use them in sea state 6+ or so (5?) due to that issue...not to mention destroyers have issues then.
Obviously the Brits hit Bismarck and Scharnhorst in bad seas, so it's not an absolute.
Though they may have just put the running depth at closer to 7m, knowing they were hitting BBs.
Likewise Subs *can* hit a shallow draft, just adjust the torpedo settings, but that takes knowing you're shooting at a shallow draft...
...but I digress.

[Kaiser Kirk]

and belatedly, the faster..and somewhat heavier armed...and deeper....version of the Sibari gunboat

Sibari IIC, Parthian Gunboat laid down 1925

Displacement:
   3,000 t light; 3,248 t standard; 3,486 t normal; 3,677 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (355.82 ft / 351.05 ft) x 49.21 ft x (12.80 / 13.35 ft)
   (108.45 m / 107.00 m) x 15.00 m  x (3.90 / 4.07 m)

Armament:
      6 - 6.50" / 165 mm 43.0 cal guns - 143.30lbs / 65.00kg shells, 266 per gun
     Quick firing guns in deck and hoist mounts, 1925 Model
     2 x 2-gun mounts on centreline, forward evenly spread
      1 raised mount
     1 x 2-gun mount on centreline forward
      2 - 6.42" / 163 mm 20.0 cal guns - 154.32lbs / 70.00kg shells, 200 per gun
     Anti-air guns in deck and hoist mount, 1925 Model
     1 x 2-gun mount on centreline, aft deck centre
      1 raised mount
      8 - 2.24" / 57.0 mm 60.0 cal guns - 6.61lbs / 3.00kg shells, 500 per gun
     Anti-air guns in deck mounts, 1925 Model
     4 x 2-gun mounts on side ends, evenly spread
      8 - 0.59" / 15.0 mm 70.0 cal guns - 0.11lbs / 0.05kg shells, 5,000 per gun
     Breech loading guns in deck mounts, 1925 Model
     2 x 2 row quad mounts on centreline ends, evenly spread
      2 double raised mounts
      Weight of broadside 1,222 lbs / 554 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.94" / 100 mm   228.18 ft / 69.55 m   11.15 ft / 3.40 m
   Ends:   Unarmoured
     Main Belt covers 100 % of normal length

   - 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:   4.33" / 110 mm   1.38" / 35 mm      3.54" / 90 mm
   2nd:   1.38" / 35 mm   1.38" / 35 mm      1.38" / 35 mm
   3rd:   0.24" / 6 mm         -               -
   4th:   0.12" / 3 mm         -               -

   - Protected deck - single deck:
   For and Aft decks: 1.38" / 35 mm
   Forecastle: 1.38" / 35 mm  Quarter deck: 1.38" / 35 mm

   - Conning towers: Forward 3.94" / 100 mm, Aft 1.38" / 35 mm

Machinery:
   Coal and oil fired boilers, steam turbines,
   Electric motors, 2 shafts, 15,840 shp / 11,816 Kw = 23.10 kts
   Range 4,930nm at 12.00 kts
   Bunker at max displacement = 428 tons (23% coal)

Complement:
   226 - 294

Cost:
   £0.866 million / $3.465 million

Distribution of weights at normal displacement:
   Armament: 245 tons, 7.0 %
      - Guns: 245 tons, 7.0 %
   Armour: 834 tons, 23.9 %
      - Belts: 428 tons, 12.3 %
      - Armament: 69 tons, 2.0 %
      - Armour Deck: 310 tons, 8.9 %
      - Conning Towers: 26 tons, 0.8 %
   Machinery: 525 tons, 15.1 %
   Hull, fittings & equipment: 988 tons, 28.3 %
   Fuel, ammunition & stores: 486 tons, 13.9 %
   Miscellaneous weights: 408 tons, 11.7 %
      - Hull below water: 183 tons
      - Hull void weights: 35 tons
      - Hull above water: 40 tons
      - On freeboard deck: 45 tons
      - Above deck: 105 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     3,713 lbs / 1,684 Kg = 27.1 x 6.5 " / 165 mm shells or 1.2 torpedoes
   Stability (Unstable if below 1.00): 1.13
   Metacentric height 2.2 ft / 0.7 m
   Roll period: 14.0 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.65
   Seaboat quality  (Average = 1.00): 1.02

Hull form characteristics:
   Hull has rise forward of midbreak,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0.552 / 0.558
   Length to Beam Ratio: 7.13 : 1
   'Natural speed' for length: 18.74 kts
   Power going to wave formation at top speed: 57 %
   Trim (Max stability = 0, Max steadiness = 100): 69
   Bow angle (Positive = bow angles forward): 13.00 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 %,  20.67 ft / 6.30 m,  18.21 ft / 5.55 m
      - Forward deck:   31.00 %,  18.21 ft / 5.55 m,  15.75 ft / 4.80 m
      - Aft deck:   34.00 %,  7.87 ft / 2.40 m,  7.87 ft / 2.40 m
      - Quarter deck:   15.00 %,  7.87 ft / 2.40 m,  7.87 ft / 2.40 m
      - Average freeboard:      12.96 ft / 3.95 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 82.5 %
      - Above water (accommodation/working, high = better): 124.4 %
   Waterplane Area: 12,079 Square feet or 1,122 Square metres
   Displacement factor (Displacement / loading): 112 %
   Structure weight / hull surface area: 66 lbs/sq ft or 322 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.70
      - Longitudinal: 1.38
      - Overall: 0.75
   Caution: Hull subject to strain in open-sea
   Excellent machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

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.

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.

165mm forward,  single 163mm aft.


            1                   3               
A (B) [a]                        Y
            2                   4


The armor is meant to defeat QF weapons as might be found on destroyers or smaller cruisers.  To allow substantial engine room, an armor deck is used, at the 2.3m level, leaving only 1 deck level unarmored.

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
35 - Reserve

AD
25t -  FC
25t - Searchlight Tower Aft (Night Fighting)
25t - LR Radio
0t - SR Radio
10t - Dedicated Air/Spotting SR Radio
20t - Squadron / FireSupport Plot Room

OD
20t : Scout Floatplane
5t : Gunpowder Cat
5t  : MSW Paravanes

1t : ASW Paravanes
2t : 2 'y' DC throwers
12t : 48 x 280kg DC


HAW
3t : CO2 compressor A/C
5t : Extra Fire Fighting
32t : Marine Squad

HBW
15t :  Enhanced Hydrophone station
10t : Basic Sonar
18t : 2 UTT 21" Bow, 6 torps
132t : Turboelectric Drive
10t : Batteries

Decks :
4.8m : Weather Deck
2.4m : Armor Deck - top of main belt
-0.1m :  1st deck
           -1.0 m : bottom main belt
-3.4m : Engineering deck
-3.9 m : Keel,

[Kaiser Kirk]

continuing the need to redesign destroyers to include Sonar,
the Palang class of 'Corvettes' aka 'Oceanic Destroyers'...aka the Parthians aren't sure how to categorize 1500 ton destroyers... when a decade ago the type was 500-750tons.

Ship naming has long been harder than expected due to
modern Persian script being Arabic, and finding "english" phonetic versions of Persian words has proven hard, I wind up with a mix of Old, Middle and Modern.
But the Destroyer series are named for predators.

Sher - Lion
Babr- Tiger
Palang - Leopard
Vakharz - Wolf

If I can, for these Wolf II and Leopard II classes I will try to find some suitable modifier like "Snow" for "Snow Leopard"
Or heck maybe Wolf II will be "Warg"...

This is an evolution of the Palang (Leopard) design,
boosting gun power while retaining the other elements.
Ultimately this sacrifices the good seakeeping,
but fits in one more 120mm guns, and better provisions for night fighting.

The 15tons reserve miscellaneous weight also gives some room for expansion and rearming of the design, whether with larger torpedoes, more DCs, a reworked armament or other.

The main battery is aligned in a pair of
two-gun mounts in A and X, with a superimposed "Y"
addressing a perceived deficiency vs. some foriegn designs

In "B" is a howitzer firing blunt nosed shells to allow forward engagement of submarines. For shore bombardment support,additional HE rounds can be stored in the 120mm mag.

Amidships is an elevated platform between the torpedo tubes, arranged en echelon are the two pairs of 57mm AA. This allows good sky arcs, and good engagement on the opposite broadside

For/aft, Paired twin GAST 15mm
are mounted to allow engagement of any plane seeking to strafe the length of the ship. These can also bear on the beam.

All guns are given bulletproof 1/4" (6mm) spray shields for strafing protection.


The Leopard / Palang Class has long range, which geared turbines will extend.
They could be "better" by pushing L:B and BC, but for the open Pacific I want a hull that doesn't push the limits to hard.

Range :
Central to this class is very long range.
6580nm + 10% for geared = 7238nm
which is sufficient to accompany the fleet in Pacific operations.

Palang II, Parthian Corvette laid down 1924

Displacement:
   1,500 t light; 1,584 t standard; 1,865 t normal; 2,090 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (392.94 ft / 387.14 ft) x 36.75 ft x (10.93 / 11.81 ft)
   (119.77 m / 118.00 m) x 11.20 m  x (3.33 / 3.60 m)

Armament:
      5 - 4.72" / 120 mm 43.0 cal guns - 55.12lbs / 25.00kg shells, 220 per gun
     Quick firing guns in deck mounts, 1924 Model
     2 x 2-gun mounts on centreline ends, evenly spread
     1 x Single mount on centreline, aft deck centre
      1 raised mount aft
      1 - 4.65" / 118 mm 21.0 cal gun - 59.52lbs / 27.00kg shells, 200 per gun
     Quick firing gun in deck mount, 1924 Model
     1 x Single mount on centreline, forward deck centre
      1 raised mount
      4 - 2.24" / 57.0 mm 60.0 cal guns - 6.61lbs / 3.00kg shells, 350 per gun
     Anti-air guns in deck mounts, 1924 Model
     2 x 2-gun mounts on sides forward
      2 raised mounts
      8 - 0.59" / 15.0 mm 70.0 cal guns - 0.11lbs / 0.05kg shells, 2,500 per gun
     Anti-air guns in deck mounts, 1924 Model
     2 x 2 row quad mounts on centreline ends, evenly spread
      2 double raised mounts
      Weight of broadside 362 lbs / 164 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.24" / 6 mm         -               -
   2nd:   0.24" / 6 mm         -               -
   3rd:   0.24" / 6 mm         -               -
   4th:   0.24" / 6 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 33,578 shp / 25,049 Kw = 31.85 kts
   Range 6,600nm at 14.00 kts
   Bunker at max displacement = 506 tons

Complement:
   141 - 184

Cost:
   £0.613 million / $2.450 million

Distribution of weights at normal displacement:
   Armament: 54 tons, 2.9 %
      - Guns: 54 tons, 2.9 %
   Armour: 3 tons, 0.2 %
      - Armament: 3 tons, 0.2 %
   Machinery: 935 tons, 50.1 %
   Hull, fittings & equipment: 425 tons, 22.8 %
   Fuel, ammunition & stores: 365 tons, 19.6 %
   Miscellaneous weights: 83 tons, 4.4 %
      - Hull below water: 25 tons
      - Hull void weights: 15 tons
      - Hull above water: 2 tons
      - On freeboard deck: 30 tons
      - Above deck: 11 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     524 lbs / 238 Kg = 9.9 x 4.7 " / 120 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.43
   Metacentric height 2.1 ft / 0.6 m
   Roll period: 10.7 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.23
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has rise forward of midbreak,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.420 / 0.435
   Length to Beam Ratio: 10.54 : 1
   'Natural speed' for length: 19.68 kts
   Power going to wave formation at top speed: 62 %
   Trim (Max stability = 0, Max steadiness = 100): 69
   Bow angle (Positive = bow angles forward): 15.00 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 %,  21.65 ft / 6.60 m,  19.03 ft / 5.80 m
      - Forward deck:   26.00 %,  19.03 ft / 5.80 m,  16.73 ft / 5.10 m
      - Aft deck:   39.00 %,  8.53 ft / 2.60 m,  8.53 ft / 2.60 m
      - Quarter deck:   15.00 %,  8.53 ft / 2.60 m,  8.53 ft / 2.60 m
      - Average freeboard:      13.27 ft / 4.05 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 172.7 %
      - Above water (accommodation/working, high = better): 147.0 %
   Waterplane Area: 8,869 Square feet or 824 Square metres
   Displacement factor (Displacement / loading): 76 %
   Structure weight / hull surface area: 31 lbs/sq ft or 152 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 0.89
      - Overall: 0.53
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform



15T - Construction reserve

AD:
5.5t - FC
0t - SR Radio
5.5t - NF Gear

OD:
2t - Lt. MS Paravanes
18t - 2TT3 21" Torpedoes
1t  -  DC "Y" thrower
1t - ASW Paravanes
0t - 2 stern rails
8t - Depth charges (32x 280kg)

HAW
1.5t - CO2 Air Compressor AC

HBW
15t - Enhanced Hydrophones
10t - Sonar

Edit : swapped the 118 'casement' to Deck, which doesn't change the Comp or composite.
Toyed with and verified that removing the Howitzer and installing a 6th 120L43 in that spot is possible,
and would just need 0.4t more fire control.

[Kaiser Kirk]

While I have refurbished the old Whale class Fleet supply vessels, they will
eventually need replacement.

The Hakma is viewed as a possible replacement.
Designed prior to the Mayan war as a series of potential vessels,

Intended to be fast enough to be hard for submarines to intercept,
while a light TDS and deep bulges are hoped to at least limit torpedo damage.
It's still Aux built, so it won't take hits well... but gives it a chance.

The provisions for an anchorage net and defensive fighters seemed like
a cautious allocation for resources, but will allow distant anchorages to
be screened.

Hakma C, Parthian Fleet Supply Vessel/ Tender laid down 1924

Displacement:
   14,992 t light; 15,357 t standard; 17,170 t normal; 18,621 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (456.36 ft / 456.36 ft) x 95.14 ft x (21.33 / 22.85 ft)
   (139.10 m / 139.10 m) x 29.00 m  x (6.50 / 6.97 m)

Armament:
      2 - 4.72" / 120 mm 43.0 cal guns - 51.50lbs / 23.36kg shells, 200 per gun
     Quick firing guns in deck mounts, 1924 Model
     2 x Single mounts on centreline ends, evenly spread
      8 - 2.24" / 57.0 mm 60.0 cal guns - 6.61lbs / 3.00kg shells, 300 per gun
     Anti-air guns in deck mounts, 1924 Model
     8 x Single mounts on sides, evenly spread
      8 - 0.59" / 15.0 mm 70.0 cal guns - 0.11lbs / 0.05kg shells, 2,500 per gun
     Machine guns in deck mounts, 1924 Model
     2 x 2 row quad mounts on centreline ends, evenly spread
      2 raised mounts
      Weight of broadside 157 lbs / 71 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Ends:   Unarmoured

   - Torpedo Bulkhead - Additional damage containing bulkheads:
      0.98" / 25 mm   273.82 ft / 83.46 m   20.47 ft / 6.24 m
   Beam between torpedo bulkheads 68.90 ft / 21.00 m

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

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 3 shafts, 19,538 shp / 14,576 Kw = 19.00 kts
   Range 7,484nm at 16.00 kts
   Bunker at max displacement = 3,264 tons

Complement:
   749 - 974

Cost:
   £1.927 million / $7.707 million

Distribution of weights at normal displacement:
   Armament: 32 tons, 0.2 %
      - Guns: 32 tons, 0.2 %
   Armour: 204 tons, 1.2 %
      - Torpedo bulkhead: 204 tons, 1.2 %
   Machinery: 644 tons, 3.7 %
   Hull, fittings & equipment: 3,952 tons, 23.0 %
   Fuel, ammunition & stores: 2,178 tons, 12.7 %
   Miscellaneous weights: 10,160 tons, 59.2 %
      - Hull below water: 5,706 tons
      - Hull void weights: 60 tons
      - Hull above water: 3,040 tons
      - On freeboard deck: 1,292 tons
      - Above deck: 62 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     31,408 lbs / 14,246 Kg = 595.7 x 4.7 " / 120 mm shells or 5.3 torpedoes
   Stability (Unstable if below 1.00): 1.97
   Metacentric height 13.6 ft / 4.2 m
   Roll period: 10.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.00
   Seaboat quality  (Average = 1.00): 1.76

Hull form characteristics:
   Hull has raised forecastle, raised quarterdeck ,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.649 / 0.657
   Length to Beam Ratio: 4.80 : 1
   'Natural speed' for length: 21.36 kts
   Power going to wave formation at top speed: 48 %
   Trim (Max stability = 0, Max steadiness = 100): 40
   Bow angle (Positive = bow angles forward): 0.00 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 %,  22.64 ft / 6.90 m,  22.64 ft / 6.90 m
      - Forward deck:   32.50 %,  14.44 ft / 4.40 m,  14.44 ft / 4.40 m
      - Aft deck:   27.50 %,  14.44 ft / 4.40 m,  14.44 ft / 4.40 m
      - Quarter deck:   20.00 %,  22.64 ft / 6.90 m,  22.64 ft / 6.90 m
      - Average freeboard:      17.72 ft / 5.40 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 95.0 %
      - Above water (accommodation/working, high = better): 122.0 %
   Waterplane Area: 33,232 Square feet or 3,087 Square metres
   Displacement factor (Displacement / loading): 146 %
   Structure weight / hull surface area: 95 lbs/sq ft or 462 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.96
      - Longitudinal: 1.44
      - Overall: 1.00
   Adequate 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

Aux build

14,992 - 24months, $0.937/HY

Intended to be difficult for opposing submarine or air patrols to damage or sink.

Designed to Cruise at 16 knots, which means a submarine that is not dead ahead will have difficulties intercepting, being forced to run on the surface at maximum speed for a prolonged period. This will only be doable in calm seas and will make them potentially visible.

This requires 7600 SHP.
Optimally, they would like this to be 1/3 of the SHP, which would put the ship at over 21.3kts, which is more 'expensive' than they want.

However, turbines are quite forgiving of long use at good power, so they put the desired cruise as less than 2/3rds power, so 18 knots.
There is a desire to be able to sprint faster than the most modern subs, so 19 knots is chosen.

Draft is kept less than 7.5m  to allow use in more areas.

Total Weaponry : 17,170 normal *.02 = 343
Torpedo Bulkhead : 204t
Guns & Mounts : 32t
Fighter Floatplanes : 100t
336t total, 7 spare

Total Fleet Supply : 6,500 tons, for 65,000 tons shipping

Void : 60 tons resv

AD
4t FC -1918
25t LR Radio
10t SR Radio - dedicated AC channels.
23t Cage Mast amidships- Floatplane control top

OD
40t : 2x Scout Floatplanes
100+10t : 4x Fighter floatplanes + 2x Gunpowder Cats.
30t Hanger structure
12t : Additional Cranes
100t : VIP Cabins
200t : Cabins
300t : Surgical wards
300t : 2x 75 ton 'Net Tender' tug.
200t:  2x 50t motorize lighters

HAW
3000t- Fleet Supply
15t  CO2 Compressor AC
25t  Extra Fire Suppresion

HBW
20t additional aviation stores
3500t - Fleet Supply
25t Extra Pumps
161t - Turboelectic Generators
2000t - Anchorage Torpedo nets and floats (see below)

Stored in holds
2000 tons - Anchorage Defense Netting & booms.
10% in booms (hollow floats) = 1800 in netting
Wt : 5lbs / Sq. Foot = 806,400 sq.ft netting
Double Wt for Anchorage/Harbor Def = 10lbs/Sq. Ft = 403,200 sq. ft netting
Depth 15m = 49.2ft
403,200 / 49.2 = 8,195 ft / 2,498m of netting.
Sufficient for a circle 397m in radius / 795m in diameter.

(weight from Wiki Desc of Bullivant nets, 1894+=5lbs/sq ft