An End Around was a World War II submarine attack tactic. It was used when the initial relative position of the submarine and its target did not give the attacking submarine a positional advantage. The submarine estimated the path and speed of the target, then submerged until the target was out of visual range. The submarine would then surface, and, remaining out of visual range, proceed at maximum surface speed to a position in front of the target. This position would give it sufficient positional advantage. The submarine would then submerge and wait until the target approached it before attacking.
The original article can be found at End Around (submarine tactic) and the edit history here.