I’ve been around the forum for a while but I guess it never came up, at least from web searches, so I thought I’d share this small trivia.
The ship in PD2 is spelled Shelcoof which transliterates to シェルクーフ in Japanese.
Actually there are French warships which are named “Surcouf”, and this also transliterates to the same word in Japanese. (Though they are more frequently referred to as スルクフ or シュルクーフ）
Out of several ships with this name, the WW2 age submarine would be the most outstanding - “the largest submarine ever built” at the time.
This name was originally taken from a “French privateer” so I guess it doesn’t have a particular meaning,
I figured the PD creators took the name Shelcoof from these warships but who knows what…