Diesel Electric Submarines: (Unedited): 18 June 2020:

China and Russia shall develop a new next generation of diesel electric Naval Attack submarines. In which the electric side of the diesel component will have an increased capability of about 4 times over all previous versions. So how long can an existing diesel electric submarine stay submerged? Multiply that by a bout four times.
With modern day quietening processes. These new submarines will be much more difficult to find.
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