We have left the pier with the sunrise, what a beatiful day to be on a u-boot

calm sea, a nice wind and a clear view. We were heading to the area BF 16 and then the moment we have waited have arrive.
Ship Spotted Herr Kaleun ! Bearing 2-9-0 .Long Range.
I have ordered to change our course to intercept the target. No escort present, We decided to make a surface attack with deck awash depth.
Open Tube 5 ! Range 500m. Speed 44 Knots. Targets Speed 11 Knots ! Bearing 185. Torpido L ..
WAIT ! What the hell ? The propeller is turning outside the water ! This is an EMPTY Cargo Ship, ABORD THE FIRE ! Return to course, Full Speed Ahead.