INS Dakar was a former RN sub. Speculation is that something happened mechanically that caused leaks forward. Upholders when the Canadians got them were not safe AT ALL
See that fiasco here.
How about the Astutes? After they were screwed up, badly, it was Electric Boat to the rescue.
Uhm... Wiki is not a good source. Photographic evidence has been provided.
Luckily, the thick inner hull protecting the nuclear reactor and the crew's quarters held.
Luckily, the sub’s nuclear reactor and the crew’s quarters were not compromised.
Initial reports indicate that the submarine's hull is intact