please please... tell me tell...
Brief comparison of Nuclear vs Conventional Sub capability / advantages / disadvantages.
1) Cost – A modern nuclear submarine is at least twice as expensive as a conventional submarine. A U-214 will cost ~ $400-500 million per sub, while even small French subs such as Rubis Amethyste Class cost close to $1 billion per sub. Chinese SSN are probably cheaper but there are no public figures available on that. So those who reason that one should have a larger fleet of conventional subs have a valid argument.
2) Sensor Suite – Modern conventional subs have quite advanced sensors. We know at least in the case if French that many sensors from their nuclear sub programmes have found their way into the conventional subs.
3) Weapons – With the exception of Ballistic missiles, conventional subs can deploy all of the weapons a nuclear sub can deploy. However, a nuclear sub is typically bigger so it can carry a bigger payload.
4) Stealth – Modern nuclear subs are much quieter than those of the past generation but even the quietest nuclear sub makes more noise than a conventional sub running on batteries. A conventional sub running on it batteries is very very difficult to find, specially in littoral waters. The stories of US nuclear subs being unable to find NATO conventional subs in exercises are well know. For a nuclear sub, there is noise from pumps, steam and electric plant, all of which can be picked up by a good sonar system. But the littoral water also offer the nuclear sub the same protection in terms of masking its noise as they would for a conventional sub, so that environment is difficult for sub hunting in any case. I once read a very good article on this specific topic of how a nuclear sub may try and offset some of its stealth disadvantage, I will try and find it.
5) Power, Range and Endurance – These are the biggest advantages that nuclear subs have over conventional submarine. They are truly independent of the surface for as long as their food supplies last. The nuclear reactor provides all the energy needed. They make their own water and oxygen, their batteries can be recharged even while deeply submerged. They can stay on-station, submerged for months. This was a huge tactical advantage.
For a conventional submarine, AIP has considerably improved the submerged time. For example Agosta 70 can stay underwater for ~ 4 days at 3.5kts with a range of 350 kts, for Agosta 90, AIP improves this by a factor of 3-5 to 10-15 days. However, they key here to understand that the range underwater is considerably decreased particularly if they go fast. U- 214 has a12,000nm range – but that is only if it is surfaced (which makes it quite vulnerable); also, its max speed is 10-12kts on surface. Its submerged range is much reduced at 420 nmi (at 8 kts) and 1248 nmi (at 4kts) on AIP/fuel cells. So while theoretically it can stay under water for 2-3 weeks, its speed and range are strongly affected in those conditions.
A conventional sub speed tops out at ~20kts under water (Agosta 90 is listed as 17kts). A nuclear sub can do at least 30kts. This considerably decreases transit time to its target and they ability to catch or out run the enemy.
For a Pakistan / India scenerio, a nuclear sub would offer the PN several operational advantages and flexibility.
1) A nuclear sub will give PN unlimited range to be threat to the entire Indian coast including the assets in the Bay of Bengal. IN will no longer be able to hide its carrier there without significant protection. Indians have built a lot of their strategic sites far south to stay out of PAF’s range. While many of SSMs can target those, this will give added options (specially when armed with cruise missiles). While a SSK can be deployed to these locations, its transit time and range are no match for an SSN as I have previously described. A nulcear sub can get to the Bay of Bengal in under 4 days at 30kts and under 2 days to the southern tip of the Indian peninsula - and it can do this while submerged to escape detection. If a U-214 attempts this entire journey submerged, it will take it 10 days, to go the journey quicker as faster speed, it will have to surface to charge batteries as the fuel cells will get depleted much quicker at fast speeds. This will make it much more vulnerable.