Like the Type 209, the TR-1700 was an export-only submarine design.

This submarine design set the former world solo dive depth record in 1985 at 1000m.

In time, these fanciful dreams became reality in the form of the first practical submarine designs.

Some of the recent Soviet submarine designs, building on technology liberated from the West, were extremely quiet.

Project 1840 is the name of a Soviet diesel-electric submarine design of which only one vessel was built.

Borelli is also considered to be the first man to consider a self-contained underwater breathing apparatus along with his early submarine design.

State-of-the-art submarine design and construction in the 1920s and 1930s made this combination of qualities very difficult to achieve.

Various new submarine designs were developed during the interwar years.

Broadband detection range is low for submarines, usually less than five miles, due to quiet submarine designs.

He eventually became a consulting engineer for a number of steamship lines and in his spare time did some work on early submarine designs.