Originally designed as high speed commence raiders, their crew soon realised that the lack of armor make them easy prey to fast firing light weapons of the very ships that they are supposed to hunt. But unfortunately many had already been completed before the flaw was discovered.
In order to make up for the mistake, the military decided to make use of the countless obsolete tanks by taking their guns and armors to improve the fight capablities the boats. In order to fool the enemy intelligence, all the refitted boats were called "Panzerschiffe" or armored ships.
Despite being fitted with more armor and a heavier new gun, the boats were still very capable of performing their role well, easily outrunning any ships thats more powerful then it is, but is more than capable of taking on any ships that can catch up to it.
While performing very well in their early year, the enemy managed to counter it with better weapons being mounted on their merchant ships, and many ships were sunk as a result. Soon the surviving ships were mostly taken off their raiding missions and many left to rust in
The E21 is one such boat which had been left to rust in the docks while her crew waited fortheir next mission