The RAND corporation publishes a number of reports and books and makes, as far as I can tell, most of them freely available as downloads.  They're a 501(c)(3) non-profit organization and have done research on a broad range of defense, technical and social issues. Here's their online bookstore: http://www.rand.org/pubs/ And better yet, here's a link that returns all of their submarine reports: RAND submarine reports

What's the largest homebuilt sub in the world?  That nicely styled and full-featured Kraka, based in Copenhagen?  Well yes, she's the largest operational homebuilt that I know of.  But her builder Peter Madsen has been working on his next project...

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