FAT Federapparat or Flächenabsuchender Torpedo (spring device or area searching torpedo), a mechanical device changes the torpedo's course over time so that it runs up- and down on parallel lines of 800 or 1600 m length
LUT Lageunabhängiger Torpedo (bearing independent torpedo), changes the torpedo's course to a preset heading directly after launch, so the launching platform (only submarines) can fire such torpedoes at targets without changing its own course.
http://en.wikipedia.org/wiki/List_of...oes_of_Germany
http://www.navweaps.com/Weapons/WTGER_WWII.htm
http://www.uboataces.com/weapon-torpedo.shtml
http://en.wikipedia.org/wiki/G7e_torpedo