The point in the XVIII in SH4 is to add at least something new to a totally daft and unrealistic addon!
The moment I read the first announcement of U Boat missions I lost my faith in Ubisoft Romania.
In reality, the purpose of the XVIII was to make submerged daylight attacks on convoys with the same speed a VII had surfaced.
It was not meant to be a "true submarine", like the XXI.
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