The virtual at sea training system or VAST allows warfighters to hone their live-fire combat skills while at sea. The Vast system is able to succesfully score precisely where the ordanance actualy landed - a significant milestone in ensuring effective at sea combat training.

VAST is actually comprised of a system by which the the ship's crew or a "spotter" sees a realistic presentation - for example, a landmass with the topography of a 'real world' target - which corresponds to an area located over open ocean.

During training exercises, the operator fires at the simulation of what they might expect to see in combat, while the ordance actualy lands within an array of buoys in the water. Exercise evaluators, monitoring the target practice on a computer screen, could be either aboard a ship or somewhere ashore.