Stern tube shuters?

[sgtmac1]

Was there a point in the production of the GATO/BALAO class where the stern tube torpedo shutters were let off as being unnecessary? I have been researching the USS TANG, SS-306 but I am not aware of that boat having them one way or another.

[ober freak]

There is a short answer: YES! Tang had stern shutters.
As all Mare Island and Portsmouth boats had them.
Open stern was an Electric Boat and Manitowoc thing (8/42 for EB {SS257} & 11/42 for Man {SS268} and onwards)