I have read in various places that the Type 23 had a torpedo tube bubble collector at the muzzle door area .. to prevent the escape of the residual bubbles which invariably dribble out when a muzzle door is opened. Even a fully flooded tube has residual air bubbles which escape prior to shooting a torpedo.
I can find no drawing or photo which shows this reclamation system or device .. or how it reclaims the bubbles back into the interior of the pressure hull. Any information will be appreciated.
I am thinking that such a device might also exist on the Type 21, since it was equally advanced in design.
