Surprise surprise, I'm not dead. This project has been completed for a while, but only recently did Chunky update so that it recognized all of the blocks I used. That's why it took so long for me to throw this out here. I've become obsessed with submarines recently, and decided to try my hand at a fast attack boat. This is supposed to be the Roman Navy's version of the US's Virginia-class in terms of capabilities and mission profile.

Specs!

Class: Diana
Type: Nuclear Attack Submarine (Designation SSN)
Manufacturer: Triton Naupegi (Ostia and Portus Julius Naval Yards)
First Commissioned: 25/08/2014
Length: 117m
Width: 23m
Height: 16m (Periscopes add an additional 7m)
Armament:

• 6 533mm Torpedo Tubes (18 Mk37 Mod 1 Torpedos)
  
• 30 Mk42 VLS cells loaded with BGM-109T Tactical Tomahawk Cruise Missiles
  

Top Speed: 30 kts
Powerplant: 1 Uranus Technologies S8U Nuclear Reactor (45 MW output). Propulsion is provided by 2 Uranus Technologies ST-30 turbines outputting 30,000 horsepower each.
Propulsion: 2 Uranus Technologies ST-30 turbines (30,000 shp total) to 1-shaft pump-jet propulsor through Uranus Technologies reduction gears.
Displacement: 7,800 Metric Tons
Commissioned Ships:

• IRS Diana (SSN 238)
  
• IRS Triton (SSN 239)
  
• IRS Mercury (SSN 240)
  
• IRS Pluto (SSN 241)
  
• IRS Fortuna (SSN 242)
  
• IRS Aurora (SSN 243)
  
• IRS Felicitas (SSN 244)
  
• IRS Iris (SSN 245)
  
• IRS Clementia (SSN 246)
  
• IRS Epona (SSN 247)
  
• IRS Nemesis (SSN 248)
  
• IRS Tempestes (SSN 249)
  
• IRS Veritas (SSN 250)
  
• IRS Luna (SSN 251)
  
• IRS Honos (SSN 252)
  
• IRS Concordia (SSN 253)
  
• IRS Justitia (SSN 254)
  
• IRS Invidia (SSN 255)
  
• IRS Libertas (SSN 256)
  
• IRS Necessitas (SSN 257)
  
• IRS Pietas (SSN 258)
  
• IRS Sancus (SSN 259)
  
• IRS Trivia (SSN 260)
  
• IRS Victoria (SSN 261)
  
• IRS Hercules (SSN 262)
  
• IRS Flora (SSN 263)
  
• IRS Charon (SSN 264)
  
• IRS Aeternitas (SSN 265)
  
• IRS Egeria (SSN 266)
  
• IRS Themis (SSN 267)
  

Crew: 120 (105 enlisted, 15 officers)
Maximum Endurance: 50 days (Limited only by food and parts availability. Reactor needs refueling every 20 years.)
Cost: 10 million denarii (At $190 USD to 1 denarius)

The Diana class was developed as a replacement for the versatile yet aging Lutetia class nuclear attack submarines that formed the backbone of the Roman subsurface force. Performing special operations, maritime patrol, reconnaissance and long-range strike missions, attack submarines could be deployed for up to 30 days before they required provisions resupply. The first priority for the Diana class project was to extend this endurance to 50 days as a response to increasingly hostile Carthaginian and Caliphate naval activity in the Mediterranean and Southern Atlantic. To accommodate the required additional storage, the Diana was almost 10 meters longer than the Lutetia, as well as almost a meter wider. The crew remained the same size due to increased automation. The second priority was enhancing the submarine's strike capability. While the capable Fulgora class guided missile submarines were the primary source of this role, the four boats could not be everywhere at once, so the Diana gained ten VLS silos on the Lutetia, concentrating its cruise missiles in 6 clusters of 5 missiles each. A constant goal with new submarines is decreasing noise, and with a pump-jet propulsor instead of a propeller, advanced insulation, and a streamlined hull, the Diana is one of the quietest submarines in any navy. Equipped with the latest sonar, including a retractable towed array, six torpedo tubes, photonic masts, and a state-of-the-art nuclear reactor, the Diana ended up being a vast improvement over the already excellent Lutetia, although at an almost 25% higher price per boat.

In a cruel twist of fate, the Diana was formally commissioned only a year before the Imperial Territories of the Skylords began their global takeover. In that year, Rome produced an astounding 30 submarines and quickly distributed them around the world. Diana classes shadowed Carthaginian and Chinese boomers, dropped off Praetorian Legion operators at several locations for missions, and collected large amounts of intelligence on Carthaginian, ITS, and Caliphate naval capabilities. The intelligence gained on ITS warships proved to be critical as the world struggled to fight back. During the invasion, one of the ITS's first priorities was disabling the Americati and Roman submarine forces, the two most competent in the world and thus the biggest threats. Unfortunately for the ITS, many Pacific Fleet subs, including almost all of the Diana classes in the region, slipped away to the polar ice caps alongside the gigantic New Broadshirian submarine navy. Loaded with supplies, with New Broadshire fast combat support subs carrying even more provisions, the combined submarine armada waited at the poles for months until an opportunity to strike back presented itself in the form of United Territories of the Skylords warships and Operation Free Will. The Atlantic Fleet subs were less lucky. With little warning, their sub bases quickly fell to orbital and airship bombardment. Any boats at sea were hunted by ITS submarines and ASW aircraft until they were either forced to surface or found and destroyed. No ballistic missile submarine bases survived, and the ITS made destroying Americati and Roman SSBNs and SSGNs a top priority. This enabled some Atlantic Fleet SSNs to escape, alongside the prides of the Roman contingent of the refugee subs, the SSBN IRS Apollo and SSGN IRS Fornax. During Operation Free Will, Diana classes operated much like German submarines during World War II, preying on ITS logistics lines and carrier strike groups until resistance forces established naval superiority. By the end of the operation, Rome had eleven Dianas at its disposal, a considerable number considering the otherwise complete destruction of its navy. The submarines were crucial in the establishment of Roman naval superiority in the Mediterranean as the world attempted to reconstruct itself. Following repairs at the ports of Ostia and Portus Julius, Rome began to rebuild her fleet, and another thirty Dianas would be built before their gradual replacement by the next generation of SSNs in the 2040s. The last Diana was formally decommissioned in September of 2042, ending a long line of distinguished service to the Empire.