Why didn't Europeans learn the shipbuilding and navigation methods of the Vikings?

Answer 1

Actual, they did learn the shipbuilding techniques of the Vikings, and some of the mediveal ships, such as the medieval Scottish birlinn, were directly descended from the Viking ships. Also, the ships in the Bayeaux Tapestry are very similar to Viking ship design. It is just that the Viking Ships were replaced by designs that were better suited for carrying cargo than the Viking ships.

The Viking ships, for all their beauty and speed, were not designed for sailing long distances carrying a lot of cargo. Their open decks would have made would have made traveling in them rather uncomfortable, and the Viking success is as much due to the hardiness of the Vikings themselves as the design of their ships. In addition, the design of Viking ships limited the maxiumum size they could be built to.

Later shp designs, such as the cog, which in part were derived from Viking designs, could carry more cargo, and so were more economical to sail, which is why they replaced the Viking ship designs. In addition, the later designs could be modified and made much bigger than the Viking ships. Navigation aids, such as the magnetic compass, would have been easier to learn and use than Viking navigation techniques.