A bit more information (edited for anonymity) from my relative in Norway, which a few of you may find of interest. He has made museum quality viking ship replicas which are displayed in several countries around the world.
The ship in Duluth was sailed over in 1926 by Gerhard Folgerø, who also wrote a book of the building and the voyage. This was not a proper Viking ship as we know, it was a double-ended lapstrake boat with a dragon head and –tail on top of the stems, he sailed all the way to Duluth. Mr Folgerø later built another, more like the normal type, and sailed this one to USA along the tradewind route to Caribia, but this voyage is not so well known. This ship was called “Roald Amundsen”, and sunk by the Germans during WW2.
The one from Minnesota came to Norway in 1982, and participated in a veteran ship meeting, where also the sailing association we belong to was present. I had then the opportunity to see a Viking ship under sail in a fresh breeze, and that was a sight never to be forgotten. Now we have several replicas sailing in Norway, so the sight is not so special any more, but I have not seen any of them under sail. It was taken back to the US on a freighter.
Then we had another Norwegian, Ragnar Thorseth, who sailed around the world in a Viking ship, the “Saga Siglar”, in 1984 – 1987. Including USA. This was a ship from the Viking period, built more for carrying capacity than speed, the type in called a “knarr”, beamier and deeper than the longship type more commonly known.
Then we have the “Gaia”, of the Gokstad type (longship), which sailed to New York and then on to South America some years ago, it is now taken care of by enthusiasts in Sandefjord and is in commission every summer.
There are many replicas presently sailing, a group in Roskilde in Denmark (where they found several wrecks from the Viking period) have tested them extensively and found that they are formidable sailboats indeed. It is interesting to learn that before these copies were sailed, the archaeologists told us that the Vikings could not sail against the wind, they had to row, to the protests of fishermen who sailed with square sails (they had no university degrees, and consequently did not know a thing), but when the replicas beat as well as any boat, they had to give in. When the Minnesota ship “Hjemkomst” (Homecoming) sailed across the Lakes, lots of sailboats came out to sail against her, not one was capable of matching the speed, also to windward. They often pointed higher, but sailed slower. Well, the Hjemkomst is nearly 70’ overall.
I am lucky enough to have built models of both the Gokstad and the Oseberg ship, 1995, that one is in scale 1:6 and 4 meters long, as long as a small canoe, I tested the hull on our pond with myself on board, the displacement was then reasonably correct. It was on a world tour before being permanently placed. The Gokstad ship is in scale 1:12, and presently in a museum. Due to this, I know more about the technical side of Viking ships than most people. They are as advanced for their age as a jet plane is today.