Nuclear vs. non-nuclear attack submarine powerplants

The budget cuts of the 1990s have placed the Navy in a difficult position when trying to maintain fleet levels capable of meeting a more dispersed and less defined threat. The cancellation of Seawolf initiated a large effort to define a submarine that is capable and affordable with today's shrinking budget. Many European countries have turned to air independent (AIP), non-nuclear propulsion systems as a way of increasing the effectiveness of their fleets when compared to their current diesel/electric boats. By evaluating and comparing two AIP and one hybrid propulsion systems to current nuclear capabilities, we can help define options for the next generation submarine. This paper attempts to provide design and cost information which can be used in conjunction with mission profiles to determine the best system for the desired job. Tomorrow's submarine will perform a variety of missions. Most all can be handled well by nuclear submarines, but at what cost? These performance/cost tradeoffs are the subject of this paper.