Excuse me,/kloc-How long does it take for a windsurfing battleship to travel from Swansea, England to new york, USA? How did you know your position at sea?

The average speed of large cross-sail warships is only 3 to 4 knots! That is, 5.5 -7.4 kilometers per hour.

The distance from Britain to the United States is about 6000 kilometers, and it will take about 45 -33 days at this speed. Considering the ocean current, wind speed, weather and other reasons, this time can be relaxed to 40 -60 days!

As for the position at sea, the navigation clock and sextant have been invented in the18th century. By measuring the position of the sun and the constellation, plus the sailing time, you can calculate your own latitude and longitude!