somewhere in the Indian ocean. but the question once more was not about Indian built hardware in my contention. the Indian leased nuclear sub is far superior to yours. for that matter nobody knows what the hell you have within the guts of your subs, your govt hides its specs to benchmark.
China had already moved on with Type 093 SSNs and been constructing Type 095 SSN. So the five Type 091 Han SSNs is nothing more than a relic now and of course they are noisy, however at least China had built a nuclear submarine more than 40 years ago on its and without any foreign assistance.
So by your logic, I can say that India Air force is crap because it still flies old airplane like mig-21 from 60s, and it keeps falling off the sky even without any enemies to face them.