Since then torpedo exercise take place with moving targets like Sachsen-class frigate “Hessen” but for sure without a warhead.
That sinking of a lame duck in a bathtub was just to appease Canadian taxpayers. 14 years after Canada bought Victoria-class submarines from the UK finally one submarine could fire a torpedo.
Naval Matters 
Last time a German U-boat sank another ship was during an exercise about 35 years ago. Destroyer “Zerstörer 1” (http://en.wikipedia.org/wiki/USS_Anthony_%28DD-515%29) was sunk by U 29 on May 16th, 1979 within 4 minutes: http://www.youtube.com/watch?v=GZ-eO2PFreg (17:40)
Since then torpedo exercise take place with moving targets like Sachsen-class frigate “Hessen” but for sure without a warhead.
That sinking of a lame duck in a bathtub was just to appease Canadian taxpayers. 14 years after Canada bought Victoria-class submarines from the UK finally one submarine could fire a torpedo.