|Shipyard||Kaiserliche Werft, Danzig (Werk 10)|
|Ordered||23 Feb 1909|
|Launched||18 Sep 1911|
|Commissioned||7 Jul 1912|
|Fate||9 Aug 1914 - Rammed by HMS Birmingham off Fair Isle. 25 dead (all hands lost).|
The engines had apparently failed as she was laying stopped on the surface in heavy fog when HMS Birmingham spotted her and could clearly hear hammering from inside the boat (presumably from attempted repairs). The cruiser fired on her but missed, and as the boat began to dive, she rammed her cutting her in two.
This was the first U-boat loss to an enemy warship.
There was another U 15 in World War Two
That boat was launched from its shipyard on 15 Feb 1936 and commissioned into the Kriegsmarine on 7 Mar 1936. Take a look at U 15 from WWII.