Cargo Ships

 

Cargo ships were used to carry weapons and food to their sides troops.  After the Lusitania was sunk and the Sussex was sunk too they started to use convoys (a group of ships or vehicles traveling together, typically accompanied by armed troops, warships, or other vehicles for protection).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Submarines 

 

Submarines were used to bomb cargo ships. Before they could bomb a cargo ship they would have to go on board and make sure they have weapons on board.  Sometimes they would have spies to watch the cargo go on the ship.  The Germans would call submarines U-boats.  These subs weren't very good.  They were dark and they could not stay under water for a very long time.