Why is the Virginia as small as it is? If larger submarines have advantages like improved stealth and more room for everything from provisions to munitions, why did the US shrink its SSN size from Seawolf to Virginia?
Seawolf was found too expensive for the post-cold war world. The US Navy was also shifting its operations from open ocean to littorals (which is still a buzzword even today) after the disappearance of the Soviet Navy.
Also during the 90s, there were a lot of discussions about the usefulness of submarines. A lot of politicians and experts argued that they were only useful for ambushing enemy vessels in places where air power cannot reach easily. In 90s, active sonar and submarine acoustic stealth improved a lot. This led to a decrease in detection ranges of other submarines by submarines while the submarine detection ranges increased for surface ships. The submarine debate got heated more. Navy submarine branches went overdrive to justify their budgets. They started talking about land attack, special forces capabilities, search and rescue and intelligence gathering. They released photos of photographed shorelines (nice capability but ISR capability of subs is a joke compared to aircraft and satellites). The USN came up with Virginia. It was supposed to be cheaper, multi-role and littoral. The idea was
- Smaller hull and shallower max depth for cheapness.
- 8 660 mm torpedo tubes were ditched and 4 533 mm tubes were adopted. Also two torpedo room design of the Seawolf was abandoned and the Virginia returned to a single room design. The torpedo storage size and reloading speed were halved.
- Decrease in propulsion power to 40k hp from 57k hp.
- Magnetic signature reduction which the USN claimed important for littoral ops
- A sonar suite better suited for littoral operations. Likely centered at a higher frequency. Mine avoidance and extra high-frequency arrays were marketed a lot.
- New ESM suite, comms suite, and periscopes for ISR. The electronic periscope was named photonic mast for marketing purposes which is technically wrong.
- Standard dry deck shelter, DSRV, mini-sub carrying capability + 9 man lock-out room. Also, the torpedo room is reconfigurable for more spec ops soldiers
- Standard 12 tube VLS for Tomahawk.
- Silence is disputed. Most reports claim it is as silent as the Seawolf. I saw some reports about its cavitation speed being higher than the Seawolf. I also saw former sailors on Quora who claim the Seawolf is actually significantly harder to find at usual open ocean patrol speeds. The Seawolf's noise level may be scaling better with speed.
So Virginia was a product of the post-cold war era when budgets halved suddenly and the usefulness of subs was being debated heavily. The USN came with a sub that was very multi-role and cheaper. They sacrificed some capabilities to achieve that ofc.
I don't know what China should do. I think it should go for a more open ocean design rather than a design focused on litorals and spec ops. The PLAAF and conventional sub fleet can do everything China needs up to a 2000 km distance from China's shores. Conventional subs can go even further to roughly 4000 km. China's nuclear sub fleet should be about sneaking into the West Pacific and the Indian ocean to pick out US assets. If the US imposes a distant blockade, its vessels will be spread thin since it doesn't have enough ships for such a task. That is what you want to see as a sub. To engage carrier groups you need missiles. Modern active sonar is no joke. So I actually think a Sino-Yasen with 32-50 VLS and 6-8 torpedo tubes is a good idea. Torpedo tubes can be larger than 533 mm to accommodate UUVs and future missiles. Spec ops missions can be done by conventional subs with less risk too. UUV capability is a must for any modern design. They may very well change everything so not having UUV launch capability would be a needless risk.
