The three ships below were designed for a game a little while back in 5. 42. They're an expression of a method that seems to work fairly well in Aurora: Long-range missiles.
Ideas for improvements are very welcome.
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A battle group consists of two or more sensor ships (the eyes), ~six long-range missile cruisers (the swords), and ~four AAM destroyers (the knives).
The overall design is optimized for distant battle. That means very good sensors, long-range missiles, and decent speed, but low sustained damage per unit time, not especially robust ships and components, and little attempt to be stealthy. A good fight is any that starts outside of enemy combat range. A bad fight is a knife fight with either mesons or anything that can pump out huge damage per unit time (lots of lasers, say).
Engines and speed: Engine tech is Internal Confinement Fusion. All engines are boosted 25% (50% loss of efficiency, 20% explosion chance), and have 50% thermal signature reduction (the hope being that this will be enough stealth at combat ranges). Fleet speed is 6000 km/s, and approximately 25% of ship tonnage and cost is devoted to engines. I've gone both higher and lower, but this seemed to be a decent balance.
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Lux Divinus class Surveillance Cruiser 15,600 tons 1117 Crew 5060. 4 BP TCS 312 TH 937. 5 EM 3060
6009 km/s Armour 20-55 Shields 102-450 Sensors 55/56/0/0 Damage Control Rating 20 PPV 0
Annual Failure Rate: 97% IFR: 1. 4% Maint Capacity 4055 MSP Max Repair 840 MSP Est Time: 2. 65 Years
Flag Bridge
Caudacus Engine (P125 0. 60 TS62. 5) (15) Power 125 Fuel Use 60% Signature 62. 5 Armour 0 Exp 20%
Fuel Capacity 500,000 Litres Range 96. 1 billion km (185 days at full power)
Epsilon Shields (S3 R450 F12) (34) Total Fuel Cost 408 Litres per day
Lynx (MR117/12. 8 R1/missile) (1) GPS 840 Range 117. 6m km Resolution 1
* This is the primary sensor. It sees HS 1 ships at 117m km and missiles at >= 12. 8 m km.
Lynx (MR784 R5000) (1) GPS 56000 Range 784. 0m km Resolution 100
* Secondary sensor. Lights up larger ships well beyond our missile range. Both primary and secondary sensors are intended to be on most of the time.
Lynx (MR35 R4000) (2) GPS 2240 Range 35. 1m km Resolution 80
Lynx (MR3. 9/0. 4 R1/missile) (2) GPS 28 Range 3. 9m km Resolution 1
* Back-up sensors - just in case a bunch of microwave-armed ships somehow gets within range. At HS 1 each, they are cheap insurance.
Keen Eye TH5-55 (1) Sensitivity 55 Detect Sig Strength 1000: 55m km
Long Gaze EM4-56 (1) Sensitivity 56 Detect Sig Strength 1000: 56m km
* Relatively weak passives. Yeah, we Romans can be stealthy, we just aren't very good at it.
ECCM-2 (2) This design is classed as a Military Vessel for maintenance purposes
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The Lux Divinus hosts the best sensors in the fleet. It's intended to see everything.
It is also expected to BE seen. When the shields and sensors go active - and my fleets tend to run around with both on - they light up this ship and attract hostile attention. That's what the 20 layers of armour (and what few shields Roman tech permits) are designed to handle.
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Martiobarbulus class Missile Cruiser 20,800 tons 1732 Crew 4540. 12 BP TCS 416 TH 1250 EM 0
6009 km/s Armour 7-67 Shields 0-0 Sensors 1/1/0/0 Damage Control Rating 14 PPV 159
Annual Failure Rate: 247% IFR: 3. 4% Maint Capacity 1910 MSP Max Repair 252 MSP Est Time: 2. 02 Years
Magazine 1548
Caudacus Engine (P125 0. 60 TS62. 5) (20) Power 125 Fuel Use 60% Signature 62. 5 Armour 0 Exp 20%
Fuel Capacity 400,000 Litres Range 57. 7 billion km (111 days at full power)
AAM Launcher (S1 RoF15) (12) Missile Size 1 Rate of Fire 15
ASM Launcher (S20 RoF750) (15) Missile Size 20 Rate of Fire 750
Warguide (MR820 R3000) (1) Range 819. 8m km Resolution 60
Warguide (MR5. 8/0. 64 R1/missile) (1) Range 5. 9m km Resolution 1
Plumbata (x12 Lancea, Sp20000 R450 SR9) (75) Speed: 20,000 km/s End: 375m Range: 459m km WH: 0 Size: 20 TH: 33 / 20 / 10
Swiftlet AAM (S1 W1 Sp57200 R13 HC-10k 160. 2%) (48) Speed: 57,200 km/s End: 3. 8m Range: 13m km WH: 1 Size: 1 TH: 534 / 320 / 160
ECCM-2 (1)
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15 size-20 launchers release Plumbata drones with a range of 450 m km. At a distance of 9 m km, each releases 12 Lanceas. Each size-1 Lancea carries a warhead of 4 at a speed of 52600 km/s for 10 m km. (Tech on the Lanceas is x8 warhead, x5 engine, x64 agility).
Per-ship throw weight is therefore 720, at a range of 459 m km, every 750 seconds. Doctrine calls for fleet to advance to effective range, release a first wave of drones, than maintain near-max range while observing results and preparing follow-up strikes. All this is great if you have time and room enough, but is lousy if you've ambushed.
The secondary weapons suite on this ship is intended to boost fleet AAM and close-in robustness while consuming little space (~600 tons including magazine storage).
The magazines are poorly designed, but serviceable. They chew up no less than 3750 tons, mostly because the Plumbatas require so much room (each Plumbata has size 8 of "dead space" and a size-12 "warhead" - the Lanceas). Fuel storage could profitably be bumped up a little.
There's only 1 primary missile control because a) they're 450 tons, and b) in the event of target and missile defences too weak to justify a full salvo, partial salvos can be rippled at successive targets every 5 seconds until all launchers have fired. If this ship is taking microwave hits, things will go badly anyway.
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Angelus - Copy class Missile Destroyer 6,250 tons 678 Crew 1587. 04 BP TCS 125 TH 375 EM 0
6000 km/s Armour 4-30 Shields 0-0 Sensors 1/1/0/0 Damage Control Rating 7 PPV 30
Annual Failure Rate: 44% IFR: 0. 6% Maint Capacity 1111 MSP Max Repair 280 MSP Est Time: 3. 72 Years
Magazine 452
Caudacus Engine (P125 0. 60 TS62. 5) (6) Power 125 Fuel Use 60% Signature 62. 5 Armour 0 Exp 20%
* We should have gone with no TH reduction and saved ~150 BP.
Fuel Capacity 260,000 Litres Range 124. 8 billion km (240 days at full power)
* This is a little high.
AAM Launcher (S1 RoF15) (40) Missile Size 1 Rate of Fire 15
Warguide (MR117. 6/12. 8 R1/missile) (1) Range 117. 6m km Resolution 1
Warguide (MR5. 8/0. 64 R1/missile) (2) Range 5. 9m km Resolution 1
Lancea (S1 W1 Sp43900 R10) (80) Speed: 43,900 km/s End: 3. 8m Range: 10m km WH: 4 Size: 1 TH: 190 / 114 / 57
Swiftlet AAM (S1 W1 Sp57200 R13 HC-10k 160. 2%) (360) Speed: 57,200 km/s End: 3. 8m Range: 13m km WH: 1 Size: 1 TH: 534 / 320 / 160
Lynx (MR3. 9/0. 4 R1/missile) (1) GPS 28 Range 3. 9m km Resolution 1
Lynx (MR35 R4000) (1) GPS 2240 Range 35. 1m km Resolution 80
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This fleet isn't particularly strong on the defence, or close-in, but the Angelus helps with both. The 40 size-1, 75% size missile launchers can be armed with either Swiftlets (for AAM work) or Lanceas (for close-in combat).
Neither the number of Lanceas (80, for a total throw weight of 320 in 30 seconds) or the number of Swiftlets (x320) is really very impressive, but this design isn't designed to excel, it's designed to be good value for money.
There's only one primary fire control. Doctrine calls for either full or rippled salvos and fleet sensors ordinarily allow plenty of time to do either (this is also why the launchers trade off a little RoF for smaller size), but in a knife fight with no time, the two backup fire controls give valuable (and, at 25 tons each, cheap) insurance.
Two small active sensors add robustness. In the event that the Lux Divinii in the fleet all have their eyes shot out, the Angelii can keep up the fight at close range. The Angelus has little armour because it's the lowest-value target in any fleet it's in and therefore the AI will probably shoot at it last.