Here is my take on the publicly available information. A submarine's strength lies in silent hunting of lone prays. As soon as you get many ships in close proximity, some of which have ASW systems available, the sub loses its advantage.
The Indian navy knows this. Hence, they will evolve their doctrine to ensure all valuable assets are at all times accompanied by ASW elements. Given they are up against 8 or more submarines, they will need a small flotilla to ensure effective counter-measures.
This plays to PN's strengths IF they are open to launching nuclear armed ballistic missiles from land into the midst of attacking flotillas. In the immediate aftermath, Pakistani subs will be able to pick off any stragglers.
PN could also equip the subs with 'tactical nukes' which basically emerge from the water and detonote in the air. Indian flotillas would live in fear of any Pak submarine sighting.
If India tries to break up its attack formations, it immediately plays into PN's hands because small pairs are prone to subs hunting in a pack.
PN will need to invest in proper shielding of the subs in radioactive waters.
@MastanKhan @Khafee @Naif al Hilali @Sarge @Oscar @Horus @Zarvan @Bilal Khan 777 @Bilal Khan (Quwa) @Windjammer
I do not agree, older diesel electric submarines had two disadvantages.
one, their battery power was limited and they have to surface or snorkel to recharge it which resulted in more chances of detection. Also they had to limit their speed greatly to increase battery time. This was the major disadvantage which led to undoing of german submarine fleet in WW2 when ships got radars. At 1-2 knots they could not get far to safety from radar detection to surface. For example, submarines built in 60s had battery power of about 6-8 hours at 5 knots, but at 1-2 knots could remain submerged for 18-20 hours and than needed to resurface/snorkel for 2 hours to recharge batteries.
Second, by 60s they had at best unguided active homing torpedoes which resulted in constraints on firing as well as no confirmation whether target was hit or not until they can verify at periscope depth which was risky.
Modern submarines have much longer battery power and with AIP can extend it significantly, e.g. If a submarine has AIP with endurance of 20 days at 5 knots, this does not mean it must surface after 20 days. Depending upon its mission and speed it maintains to get in its area of operation and out, it can remain submerged for significantly longer duration possibly for the entirety of its mission. Also oxygen based AIPs can recharge their tanks and batteries quickly if needed via snorkeling. Depending upon operational requirements, a submarine can be designed to remain fully submerged for entirety of its operation and food stock.
Being very silent and most active sonars limited to at best tens of nautical miles and with newer cable controlled battery powered passive torpedoes and anti ship missiles, such a submarine can actually take on more than a couple of surface threats. A wolf pack of 2-3 such subs can hunt and destroy a sizeable battle group.
Indian Navy has a different strategy, it is planning to project power away from its home. PN strategy is to defend its coast and important assets and try to keep open vital lines to gulf and red sea. I agree with you that it is short on both surface and submerged elements presently but it is trying to rectify this. It is setting up an AShM based coastal defence system, It is increasing it's submarine fleet and also inducting more fast petrol boats with AShMs and probably may induct a few more lighter frigates in future. Also PAF has setup relevant assets with air-surface munitions to provide a good ranged umbrella. This will ensure that it will have a balanced defence force with capability to strike and keep IN fleet vary of getting closer.
What will be the purpose of inducting more surface vessels? Do you want PN to get out of its safety umbrella to strike an Indian battle group?
Naval battles because of mobility of surface and submerged combatants have always tended quickly to turn into fleet to fleet battles. That will be done deal against Indian western fleet.
Lets suppose you can some how, probably using Aladdin's lamp, secure finances and increase your frigates strength to 20+, also now that we are day dreaming lets throw in a few top notch destroyers as well.
Now against a 40-50 ship opposing fleet with its own air cover, what will be the result? You will have your a$$ handed over to you..
Historian will forget about Nielson's victory or American victory in battle of midway and will remember our stupidity for a long time.