ステルス潜水艦

下記の記事が出ている。

　Saab unveils superstealth 'ghost submarine' that is virtually invisible to enemies and even allows divers to silently enter and exit
　Daily Mail: 2 July, 2015
　http://www.dailymail.co.uk/sciencetech/article-3147721/Saab-unveils-superstealth-ghost-submarine-says-virtually-invisible-enemies-allows-divers-silently-enter-exit.html