Yeah, I remember something similiar happening in the Torpedo Attack tutorial with the Mogami Cruiser. I was practicing my manual targeting on the Mogami Cruiser and after sinking her I decided to look for other targets. Anyway, I saw a fishing boat in the distance and decided to take a shot at her. I manually set everything up as usually and fired two torpedoes at her. The first torp hit directly in the centre and she flew in the air. It was hilarious, so much I couldn't stop laughing.. Now I wish I took a screenshot of it!
The funniest thing was though, the other torp sailed straight through as the boat was in the air!