Your Nation's Warships, Batch 3

[Gallia-]

4) It must escort a convoy out and in without refueling. 15,000nmi at 18 knots.

Can it not UNREP with a DD tender or a fuel tanker in the convoy or something? It wouldn't need to be a conspicuous ship, or even anything special, since the USN has done STREAM with civil tankers before.

[Fuso-]

Tangentially... how fast can you print a 2,000-3,000 ton frigate to go chasing off PRC'ian Romeos/Mings off of your trade?
This thing needs to be a little beefier than the irl Abukumars, i.e.
1. Needs a thwuppo
2. A 16-24 cell VLS battery for VL-ASROC memes and some half-assed air self-defence measures (i.e. CAMM)
3. A decent enough sonar system to do its job of chasing diesels
4. Good enough range to cross the Pacific with one UNREP.
5. Be able to fight a Type 056 just in case.

[Gallia-]

abukuma was launched in like 22 months, so maybe 18-22 months depending on the experience of the shipyard?

[Velkanika]

What Galla said, but the electronics fit of a warship that size has a significant impact on construction time. AN/SPY-1 arrays, towed array sonars, and many of the computers that run the Aegis Combat System for example are not commercial off the shelf tech - they are built to order with significant lead time required.

[Velkanika]

Closed RP region has an ice-free Antarctic, over which my major sealanes travel. Mulling some sort of dedicated long-range "trans-polar escort:"

1) Weapons set is mainly ASW, its AAW suite would be self-defense only (Tor, Kortik/Pantsir, AK-725). A larger derivative in the future would be equipped for AAW.
2) Aviation complement is 2 helicopters (~Z-9) with hangars.
3) Powerplant must be diesel, because:
4) It must escort a convoy out and in without refueling. 15,000nmi at 18 knots.
5) To maintain its speed it uses an X-bow to punch through the Roaring Forties/Furious Fifties/Shrieking Sixties at speed.
6) Flank speed is not a concern. I'm ok with a top speed of 27~28 knots.

Crew comfort not a concern. What is the minimum practical displacement I would be be looking at?

15,000 nmi without refueling is theoretically possible, but your ship is going to have to have a disproportionately large quantity of displacement dedicated to fuel tanks. This is going to give you an awkward design - you're going to get a 10,000 or 12,000 ton ship armed roughly the same as an old Perry-class FFG. That ship is useful, but completely overpriced for what you'd get.

Nuclear marine propulsion can get you that range on a much smaller platform (around 3,000 or 4,000 tons if we're talking current technology) but costs a ton, plus requires access to nuclear fuel and reactor technology. Again, a very useful ship and more useful than the first option given that it has unlimited range at 30+ knots, but expensive and time consuming to build.

Option 3 was already suggested, which is UNREP. If your navy has a Sea Line of Communication that long it should have fleet tenders, and if not it's reasonable to assume they can convert a merchant ship to act as one. I recommend going with this option, and attach an UNREP group to the convoys or have one or two independent UNREP groups shuffling between convoys to reload, refuel, and resupply shorter range escorts as they leave the "hot" zones or reach the limits of their internal fuel supplies. Ideally, you should look for an island or something you can use as a staging area and either negotiate access or send in the marines to occupy it.

[Triplebaconation]

15,000 nmi without refueling is theoretically possible, but your ship is going to have to have a disproportionately large quantity of displacement dedicated to fuel tanks. This is going to give you an awkward design - you're going to get a 10,000 or 12,000 ton ship armed roughly the same as an old Perry-class FFG. That ship is useful, but completely overpriced for what you'd get.

lol

[Gallia-]

you're going to get a 10,000 or 12,000 ton ship armed roughly the same as an old Perry-class FFG

oh god oh fuck

[Ormata]

you're going to get a 10,000 or 12,000 ton ship armed roughly the same as an old Perry-class FFG

oh god oh fuck

That doesn't fit his range criteria (expanding it could be done I suppose, though the increased drag makes it a tad more complicated). Also doesn't meet his helicopter requirement.

[Gallia-]

Bruh NSC literally meets Titty's range requirements if it goes like 16-18 kts in good seas, meet the range requirement if it has an extra fuel tank (you can replace the turbine with this), and it carries two Seahawk sized helicopters. The only thing he lacks is gunfire platform stability and the crew spaces are a bit too bourgeois.

[Ormata]

Bruh NSC literally meets Titty's range requirements if it goes like 16-18 kts in good seas, meet the range requirement if it has an extra fuel tank (you can replace the turbine with this), and it carries two Seahawk sized helicopters. The only thing he lacks is gunfire platform stability and the crew spaces are a bit too bourgeois.

I saw only one helicopter on that link. The 2x are small drones. For the fuel, fair enough (wasn't aware an extra fuel tank would get you that far).

[Gallia-]

There are two Z-9/MH-65/MH-60T sized hangars.

418's are what a modern Perry would look like if it were designed by relative amateurs and stripped of its combat systems in favor of additional berthing/endurance storage.

[Ormata]

(Image)

There are two Z-9/MH-65/MH-60T sized hangars.

418's are what a modern Perry would look like if it were designed by relative amateurs and stripped of its combat systems in favor of additional berthing/endurance storage.

Well hell.

The infobox for the Legend class cutter has only one aircraft listed, as well as only one hangar listed.

[Austria-Bohemia-Hungary]

What Galla said, but the electronics fit of a warship that size has a significant impact on construction time. AN/SPY-1 arrays, towed array sonars, and many of the computers that run the Aegis Combat System for example are not commercial off the shelf tech - they are built to order with significant lead time required.

Assuming you were referring to my frigate musings... I don't need AEGIS for this one, note No. 2:

2. A 16-24 cell VLS battery for VL-ASROC memes and some half-assed air self-defence measures (i.e. CAMM)

[Velkanika]

Bruh NSC literally meets Titty's range requirements if it goes like 16-18 kts in good seas, meet the range requirement if it has an extra fuel tank (you can replace the turbine with this), and it carries two Seahawk sized helicopters. The only thing he lacks is gunfire platform stability and the crew spaces are a bit too bourgeois.

NSC can't do 15,000 nmi at 18 knots, and is not survivable against ASCMs or air power. Its defenses would be saturated by two or three guided weapons of any kind, including smart bombs. An F-18 could sink an NSC with three or four GBU-54s with immunity from retaliation, and that would get easier with standoff weapons. They have CIWS and a 57mm deck gun for air defense, they're sitting ducks in a shooting war

What Galla said, but the electronics fit of a warship that size has a significant impact on construction time. AN/SPY-1 arrays, towed array sonars, and many of the computers that run the Aegis Combat System for example are not commercial off the shelf tech - they are built to order with significant lead time required.

Assuming you were referring to my frigate musings... I don't need AEGIS for this one, note No. 2:

2. A 16-24 cell VLS battery for VL-ASROC memes and some half-assed air self-defence measures (i.e. CAMM)

Oh, fair enough. Still though, towed array sonars and whatever radars and other sensors and the processing systems it does have all add a lot of time to construction. Those do not come off of a factory line like tanks do

[Gallia-]

nsc goes 12,000 at 16-18 kts on a single diesel lol

[Taihei Tengoku]

The defenses on the escort are no more than point defense, probably going to stick Kashtan and Tor on it and call it done, and then a canister of Klubs on the fantail. I am not seriously concerned about air defense because it will operate in awful Antarctic weather and the leg most vulnerable to air attack can be covered by land-based fighters.

[Velkanika]

nsc goes 12,000 at 16-18 kts on a single diesel lol

Then why did it loose so handily to FREMM for FFG(X)?

The defenses on the escort are no more than point defense, probably going to stick Kashtan and Tor on it and call it done, and then a canister of Klubs on the fantail. I am not seriously concerned about air defense because it will operate in awful Antarctic weather and the leg most vulnerable to air attack can be covered by land-based fighters.

SA-N-9's are great at engaging guided missiles so you should absolutely leave that on there because I guarantee that IRL, they would be attacked from the air if not by fixed-wing aircraft then by long-range ASCMs fired from ships or submarines. The plausibility of NS RP varies considerably, but realistically they're at risk of missile attack even in the Antarctic circle. ASCMs often have ranges in excess of 100 nmi and can be fired from high altitude, so it's conceivable that a ship in a storm could be attacked by an aircraft flying either in good weather outside of the storm or above it entirely. They might not work in a hurricane, but most existing missiles will work in the usual trashy polar weather just fine. The Southern Ocean is usually a near gale with frequent gale-force wind, which translates to Sea State 6 and common anti-ship missiles can handle that just fine.

[Gallia-]

nsc goes 12,000 at 16-18 kts on a single diesel lol

Then why did it loose so handily to FREMM for FFG(X)?

incredible

[Minskiev]

Wow, I would be poking fun at you for being such nerds, but I’m this exact way with tanks, so...

[Taihei Tengoku]

The defenses on the escort are no more than point defense, probably going to stick Kashtan and Tor on it and call it done, and then a canister of Klubs on the fantail. I am not seriously concerned about air defense because it will operate in awful Antarctic weather and the leg most vulnerable to air attack can be covered by land-based fighters.

SA-N-9's are great at engaging guided missiles so you should absolutely leave that on there because I guarantee that IRL, they would be attacked from the air if not by fixed-wing aircraft then by long-range ASCMs fired from ships or submarines. The plausibility of NS RP varies considerably, but realistically they're at risk of missile attack even in the Antarctic circle. ASCMs often have ranges in excess of 100 nmi and can be fired from high altitude, so it's conceivable that a ship in a storm could be attacked by an aircraft flying either in good weather outside of the storm or above it entirely. They might not work in a hurricane, but most existing missiles will work in the usual trashy polar weather just fine. The Southern Ocean is usually a near gale with frequent gale-force wind, which translates to Sea State 6 and common anti-ship missiles can handle that just fine.

Perhaps. The plausible enemy doesn't have infinite MPAs or submarines but I don't have infinite technology either (~late 00s China). It would be nice to print Burkes/Luyangs but I cannot, and in any case there would be AAW destroyer leaders in the escort package

[Velkanika]

SA-N-9's are great at engaging guided missiles so you should absolutely leave that on there because I guarantee that IRL, they would be attacked from the air if not by fixed-wing aircraft then by long-range ASCMs fired from ships or submarines. The plausibility of NS RP varies considerably, but realistically they're at risk of missile attack even in the Antarctic circle. ASCMs often have ranges in excess of 100 nmi and can be fired from high altitude, so it's conceivable that a ship in a storm could be attacked by an aircraft flying either in good weather outside of the storm or above it entirely. They might not work in a hurricane, but most existing missiles will work in the usual trashy polar weather just fine. The Southern Ocean is usually a near gale with frequent gale-force wind, which translates to Sea State 6 and common anti-ship missiles can handle that just fine.

Perhaps. The plausible enemy doesn't have infinite MPAs or submarines but I don't have infinite technology either (~late 00s China). It would be nice to print Burkes/Luyangs but I cannot, and in any case there would be AAW destroyer leaders in the escort package

Fair enough. This is probably a good time to ask what exactly your potential adversaries have that could theoretically attack these ships at sea when they're performing their design role. We talking SSNs and carriers, long-range land-based naval aviation, or a bunch of SSKs and frigates?

[United Earthlings]

Closed RP region has an ice-free Antarctic, over which my major sealanes travel. Mulling some sort of dedicated long-range "trans-polar escort:"

1) Weapons set is mainly ASW, its AAW suite would be self-defense only (Tor, Kortik/Pantsir, AK-725). A larger derivative in the future would be equipped for AAW.
2) Aviation complement is 2 helicopters (~Z-9) with hangars.
3) Powerplant must be diesel, because:
4) It must escort a convoy out and in without refueling. 15,000nmi at 18 knots.
5) To maintain its speed it uses an X-bow to punch through the Roaring Forties/Furious Fifties/Shrieking Sixties at speed.
6) Flank speed is not a concern. I'm ok with a top speed of 27~28 knots.

Crew comfort not a concern. What is the minimum practical displacement I would be be looking at?

Such a vessel is theoretically possible, I'm just not sure the cost of building such a class of vessel would be worth the expense in the end, whose almost entire design purpose is to achieve a very long range endurance. Such a design doesn't leave much wiggle room for weapons fittings, let alone takes into account future growth requirements when, not if such requirements become necessary.

Where others have cited the Legend class cutter, as a beginning basis I instead choose to go with the British Type 23 Duke Class seeing as a dedicated warship it already has the longest sailing range of any modern warship I could locate that at best closely approximates your stated requirements. Starting from there using the Type 23s dimensions, I ran it through SpringSharp because if a late 1940s design is theoretically possible, it stands to reason a 21st century version would be theoretically possible too, like the use of an inverted X-bow.

The design {works} and on paper actually looks pretty good, but you’re going to have one hell of a fine hull shape. To get the lowest possible displacement, I took it as low as the block coefficient would let me, 0.300. I don't know if you could make a RL design work, but as I said I was only interested in the theoretically possible. I'm sure a more refined design would intend various compromises.

As for the type of propulsion system used, I'm thinking the same type found on the Type 23 would probably be the best. A CODLAG (combined diesel-electric and gas) with 1 gas turbine and 2 to 4 diesels optimized for maximum fuel efficiency.

Displacement:
3,186 t light; 3,282 t standard; 4,732 t normal; 5,891 t full load

Dimensions: Length overall / water x beam x draught
436.35 ft / 436.35 ft x 52.82 ft x 23.95 ft (normal load)
133.00 m / 133.00 m x 16.10 m x 7.30 m

Armament:
1 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1950 Model
Dual purpose gun in a deck mount with hoist
on centreline forward, 1 raised gun
Weight of broadside 14 lbs / 6 kg
Shells per gun, main battery: 220
2 - 12.8" / 323.85 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 1.00" / 25 mm 283.63 ft / 86.45 m 8.72 ft / 2.66 m
Ends: 1.00" / 25 mm 152.70 ft / 46.54 m 8.72 ft / 2.66 m
Upper: 1.00" / 25 mm 283.63 ft / 86.45 m 8.00 ft / 2.44 m
Main Belt covers 100 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.50" / 13 mm - -

Machinery:
Diesel Internal combustion generators,
Electric motors, 2 shafts, 28,118 shp / 20,976 Kw = 28.00 kts
Range 15,000nm at 18.00 kts
Bunker at max displacement = 2,609 tons

Complement:
284 - 370

Cost:
£1.619 million / $6.477 million

Distribution of weights at normal displacement:
Armament: 2 tons, 0.0 %
Armour: 249 tons, 5.3 %
- Belts: 248 tons, 5.2 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 1 tons, 0.0 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 673 tons, 14.2 %
Hull, fittings & equipment: 1,763 tons, 37.3 %
Fuel, ammunition & stores: 1,546 tons, 32.7 %
Miscellaneous weights: 500 tons, 10.6 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
9,824 lbs / 4,456 Kg = 727.7 x 3.0 " / 76 mm shells or 2.3 torpedoes
Stability (Unstable if below 1.00): 1.08
Metacentric height 2.2 ft / 0.7 m
Roll period: 14.9 seconds
Steadiness - As gun platform (Average = 50 %): 100 %
- Recoil effect (Restricted arc if above 1.00): 0.01
Seaboat quality (Average = 1.00): 1.52

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.300
Length to Beam Ratio: 8.26 : 1
'Natural speed' for length: 25.10 kts
Power going to wave formation at top speed: 50 %
Trim (Max stability = 0, Max steadiness = 100): 66
Bow angle (Positive = bow angles forward): -2.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 26.25 ft / 8.00 m
- Forecastle (20 %): 14.63 ft / 4.46 m
- Mid (50 %): 14.63 ft / 4.46 m
- Quarterdeck (15 %): 14.63 ft / 4.46 m
- Stern: 14.63 ft / 4.46 m
- Average freeboard: 15.56 ft / 4.74 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 59.0 %
- Above water (accommodation/working, high = better): 147.7 %
Waterplane Area: 15,390 Square feet or 1,430 Square metres
Displacement factor (Displacement / loading): 224 %
Structure weight / hull surface area: 74 lbs/sq ft or 359 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.92
- Longitudinal: 2.52
- Overall: 1.02
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

[Triplebaconation]

That's utterly useless because:

A) Springsharp doesn't calculate diesel fuel consumption correctly even for the era it covers.
B) It's not even a remotely accurate model of the Type 23 since it uses wiki infobox dimensions instead of the specific ones Springsharp requires.

For a 4-5000 ton ship you'll need about 800-1000 tons of diesel for the range requirement.

[Republica Federal de Catalunya]

For my navy endurance is not a major concern. Normally 8000-9000 nm endurance is considered more than enought for most of my Frigates (Destroyers size and capabilities). In general my longest deployment has been the Somali coast antipiracy patrol. My navy normally operates in North Atlantic and Mediterranean. With some habitual desployments in the Baltic, Caribbean and western indic ocean.

[Mitheldalond]

Forget Legends and Type 23s. Just use this (or this for an armed example).

Meets or exceeds aircraft, diesel powerplant, and range requirements, and has the added benefit of not caring how much ice/weather you put in front of it (though I'm now noticing you mentioned an ice-free Antarctic). Just bolt a couple Mk 48 VLS modules for Sea Sparrows/ESSMs to the sides of the hangar Karel Doorman style, add a gun and a pair of Harpoon launchers to the bow, plonk a CIWS down somewhere, stick on your preffered model of Sea Girrafe radar, and call it a day. The only thing really lacking is flank speed.

Alternatively, if you want to get a bit crazy and go for super ultra maximum range: sailboats.

That's utterly useless because:

A) Springsharp doesn't calculate diesel fuel consumption correctly even for the era it covers.
B) It's not even a remotely accurate model of the Type 23 since it uses wiki infobox dimensions instead of the specific ones Springsharp requires.

For a 4-5000 ton ship you'll need about 800-1000 tons of diesel for the range requirement.

Springsharp also doesn't calculate the weight of toredoes at all (or maybe it just does it wrong, I don't remember). The same is probably true of depth charges, etc.

I'm also pretty sure that it overestimates horsepower requirements to attain a given speed, though that could be a result of the limited control we have over the actual hullform of the ships. I also believe it places far too much weight on speed when it comes to calculating seakeeping (I don't buy that my knock-off HMS Devastation is a good seaboat, no matter how slowly it goes).