Doubt about sinking subs with one torpedo.

[Sub Sailor]

Gentleman;
In most cases and even on the surface a sub being hit by one of the heavy weight fish will sink.
A problem for, at least US Boats, lack of compartments, almost any major hull breech will be enough to sink the boat. I don't know the compartment layouts of other countries boats.
I agree many of the light weight fish will not sink a sub , example the 46, but again depth is always a major factor. I would think a double hull boat could take a hit by a 48 and possibly not sink, but down at max depth she would rupture. Probably a Typhoon could take 3 maybe even 4 hits by Mark 50s or 46s.
US Boats even the Ohio class have very large compartments, compare any of our Nuke boats with a WWII boat. My first boat USS Swordfish SSN 579 had more compartments than a 688. The secret don't get hit. One of the things we learned from Thresher was it would be possible to draw residual heat from the core to drive yourself to the surface. We developed sub safe with emergency blow to utilize this. If a hit did not scram the plant you good go to flank and hit the chicken switch and maybe make it even with say the bow compartment flooding, but it would be a close thing.

Respectfully,

Ron Banks MMCM(SS), USN(Ret)