The simulator of the present invention comprises a submersible structure to be used in a body of water, for instance a pool. This structure comprises a bell defining a main chamber. An escape tower is provided over the bell. This escape tower defines an escape chamber communicating with the main chamber. The escape tower has a lower hatch between the main chamber and the escape chamber, and an upper hatch separating the escape chamber from outside the submersible structure. The simulator also comprises a mechanism for vertically moving the submersible structure relative to the water surface. A method of performing underwater submarine escape training is also disclosed. The simulator allows such training to be conducted in a safe and controlled environment.