Yes....I do know littoral means close to shore. Probably comes from lighters which were used for cargo.
THe point I wass making with these was small ships which normally could operate at 20 knots but could perform for some time at the speed the website quoted.
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I think the only people who really know what they are are not likely to tell us. I do notice that the tracks of the Pilot Boat Parmelia however are pretty accurate so presumably these tracks are not too inacurate either.