A Viking Ship by Peter Sjolander of Fullerton California in 1986

While I was building a windsurfer, the directions said that a windsurfer obtained its speed by tilting the sail into the wind, causing lift. When I was in Norway, I visited the Viking ships. I was struck by how hardy they were, like they could ride out any storm. I though at the time, if only they had had good sails, they could have gone anywhere in any weather. The Viking sails always seemed like a paradox to me. How could any sailors with such fine boats have such poor sails? It wasn't until I was building the windsurfer that it hit me that it wasn't the Viking sails that was poor, it was our perception of those sails. We had always seen them as having big strips of color. It hadn't occurred to us that this outward appearance of color hid a sailing technology that was as advanced as the ships.

At this point I started looking for the lost art of the Viking sails. The art was "lift". I felt the Vikings had used lift to make their sails as advanced as their ships. I started researching Viking sails and ships. Much is known about the ships because the are made of wood. Nothing is known about the sails.because they are made of cloth.

Viking Ships
The soft parts of Viking ships leave very little behind after a thousand years. Thus, in my model, I have attempted to build the ship from the bottom up. I have tried to build a ship capable of performing according to legend.

I built the sails completely different from any I have seen. I figured that each runic stone artist saw a different perspective of the ship. I also built the sails so they have a tremendous amount of controllable power which would perform progressively better the worse the storm. This would explain the legend which said the Vikings raided a village forty miles up a shallow river in a howling storm. Then it took them a month of pulling through the mud to get the ship back to sea.

While designing the sails and calculating lift, I discovered the oars could be used as lifting surfaces. When I read that the rudder was built in an airfoil shape to allow for the fact that it was mounted on one side I knew the Vikings understood the concept of lift. Thus, I mounted the oars in the position of outrigger hydrofoils. These outriggers allowed the Vikings to cross snow as easily as water making overland winter travel as easy as summer, as Eric Oxenstierna writes in his article titled "The Vikings" in Scientific America. "They advanced in their light ships across eastern Europe as if its meadows and forests were the open sea." I mounted the boom in the center of the ship because the runic stones show it in that position.
My Viking Sails
The Viking, sails were highly prized gifts. They are spoken of in legend as swans beating their wings. I picture these sails as crescent moons sailing through the night sky.

On my model there are six sail columns, each made up of five sails for a total of thirty sails. The rigging of the six columns all tighten when the boom is raised. Each of the five sails in a column work together, however, each column is independent of the other columns in its angle of lift and angle of bank.

Each of the sails is made of three different parts. The first part I call the leading edge. The second part I call the bow string. The third part I call the sail cover. The leading edge of the sail is made of wood and is like the bow part of an archer's bow. It is stiff yet flexible. The part of the leading edge corresponding to the handle on a bow is made thicker than the rest, to allow for a precise pivot action of the rigging. The bow string of the sail is the same as the bow string on an archer's bow with one exception, the string is drawn in toward the leading edge. Whereas, on an archer's bow the string is pulled away from the bow while pulling on the arrow. This drawing in toward the leading edge gives the sails the inside shape of the crescent noon.

The sail cover is described in the literature as two sided "pell". On my model rip stop nylon is stitched into the crescent moon shape, turned inside out and the bow strung inside the sail cover.

My Viking Oars

On my model the oars have two uses. The first was to move the ship along by manpower at low speed. The second use, as an outrigger hydroplane surface. When the ship was moving fast enough so it no longer needed manpower to move it, the sailors would lock their oars at a thirty degree slope to the water with the paddle of the oar tilted up ten degrees to the forward motion of the ship to the water. This ten degree upward tilt would give the oar the capability of hydroplaning through the water , thus giving the ship added stability while at the same time cutting down on the wetted surface and reducing the drag on the vessel as a whole.

D ur i n g the winter the Vikings would prefer to sail over snow in their ships because the travel tine would be much shorter. The oars would be placed in the same outrigger hydrofoil position as they were in the water, and if there was enough wind the sails would be used in the same manner. However, if the wind was coining from the direction they were traveling, they would harness their reindeer to the ship and sail into the wind.

The deer would be harnessed to the ship one to each oar. The rope would be twice as long as the deer so it could run in the space between the hull and the oars. The deer would also be harnessed to the front because when the ship was going down hill the deer could glide and not hit the ground . Under ideal conditions of head wind and down hill speed the ship would become airborne for short hops, provided the sails were all set head on and flat acting like glider wings.

The Keel

The keel on Viking ships acts like a Iong waterski. With the mast mounted ahead of center and the sails providing lift the keel attains a one degree lifting angle. This one degree angle is so important that the oars near the front of the ship may be set at more than ten degrees so the keel will ride at the desired one degree. The oars near the back of the ship may be set at nine degrees to trim the keel to the desired one degree angle.

The Mast

The mast need not be strong or tall. It takes all of its force like an arrow, through the length. The mast is light so it is easy to take down and put up. For instance, when going along narrow tree covered streams. The mast is set ahead to give lift to the front of center so the hull and keel will be at a one degree angle to the water to give easy planing and hydroplaning.

The Rudder

The rudder on the side provided me with an important piece of information. The Vikings knew about lift. The rudder has lasted for the last thousand years because it is made out of strong wood. Because of the side mounting position the rudder causes a slight drag on the boat to want to turn to that side. Thus the Vikings shaped the rudder like an airfoil to compensate for the drag caused by the side-mounting.

The Viking Shield

The Viking Shield had many uses. The first and best known use is as a battle shield. Its second use I have given is a stand for the oars when they are in hydrofoil position. One of the reasons I used the shields for oar stands is that my model looks like many of the runic stone carvings of Viking ships. The shields all stand vertical along the side of the ship.

The Viking Sailor

The Viking Sailor wanted to make everything around him have more than one use. He wanted everything on the ship to be very taut. In recruiting Viking ship sailors today I would require them to know how to windsurf, water ski, snow ski and hang glide. All of these skill come into play sailing a Viking ship.

The Viking Rigging

I built the rigging so that all the ropes that go from the deck to the mast are under the same tension. The boom has all its support rigging set in such a way that it will not bow from the tension of the ropes from the deck. The ropes that come up out of the deck I put in place to attach the rigging to and also use for miscellaneous tie down points. All the ropes attach to the frame cross members that form the ribs of the hull. This placement gives the tie downs great strength and at the same time have a clean look going into holes or slits in the deck.

In Conclusion

A Viking ship rigged like my model could be capable of very high speed. The world speed record for a wind powered vehicle was set in a ice boat in a howling gale.

I am building two proof of concept vessels. The first is a four oar model with a PVC pipe for a hull. This is to test the outrigger hydrofoil design. The second is a six oar, six sail model with a fiberglass canoe hull. This is to test the sail design.

Anyone reading this booklet
that wants to help me in any
way please write to me at the
following address:
Peter Sjolander
1518 West Avenue
Fullerton, California 92633 USA