Designed to replace the Ohio-class submarines upon their retirement in 2029, the awkwardly named Ohio Replacement Programs’ (ORP) subs will enter construction in 2021. Although there are a number of improvements in this new fleet of ballistic subs, the most dramatic changes will be in the boats’ engine room. Where its’ predecessor used traditional mechanical propulsion technology, the ORP subs will feature an electric propulsion system.
A nuclear reactor will still create the power that pushes the craft through the water. However, unlike current Ohio-class subs the new system will connect the boats reactor to an electric motor that spins the boat’s propellers.
According to the Navy, switching from a mechanical to an electric system will dramatically reduce the noise the ORP subs create.
Aside from creating a stealthy ship the electric propulsion will also help the ORP subs generate electricity for the ships electronics, sensors and weapons systems.
The ships will also be home to a new nuclear reactor whose core is designed to last 42 years. Not having to refuel the reactor will provide huge efficiencies compared to the multi-year refueling process associated with the current Ohio-class submarines.
Currently the US Navy has plans to build a dozen ORP subs. However, given their $4 billion per unit price tag, the Navy could reduce that number between now and 2021.
Image Courtesy of the US Navy