Experimental trips and sea trials.

We cannot master the wind!
Poul Nygaard, Roar Ege Boat guild, 2007

The same years that Roar Ege is launched, the boat guilt undertakes 14 days of sea trials in Isefjord. From the harbour in Nykøbing Sjælland, the crew choose a route to test the ship's ability to beat to windward and experiment with rowing. In light winds of less than 5 m/s, it turns out that it is better to row than beat to windward. With six oars Roar Ege reaches a good top speed of 3.2 knots, and over a longer distance the ship can be rowed at 2.0 knots. Beating to windward, by contrast, gave an average speed of just 1,7 knots.
The following year the boat guilt takes another 14-day trip, this time to test the ship on the open sea of Kattegat. The little trading ship struggles in the high waves, and water comes in across the gunwhale in the foreship. We can conclude that Roar Ege is not an ocean-going ship.

Helge Ask takes part in a sailing race in Isefjord in 1993. The wind is strong and gusting, and during a tacking manoeuvre, the ship capsizes. Everyone on board is safe, but the experience teaches us that in strong winds it is safer to veer than to tack with a square-sailed ship.

The small longship is a combined rowing and sailing craft. In 2005 the ship participates in a rowing race with Kraka Fyr and Roar Ege. Over a short sprinting distance Helge Ask reaches 5 knots, and over a longer stretch it is rowed at 3.5 knots. At such speed, Skuldelev 5 could easily have patrolled Danish waters.
The mast can be lowered in warships like Helge Ask. This makes it easier to row against the wind, and increase the rowing speed. For long distances or in poor visibility the ship is less visible, and can sail closer to land before it is seen.

A few month after launch, Kraka Fyr sails to the Danish island of Anholt. Despite a stiff gale, it turns out to be extremely seaworthy. But the round-bottomed boat rolls somewhat in the high waves, and now and the water comes in over the gunwhale.
Skuldelev 6 is originally built with six strakes, and is used for coastal fishing along the coast of Norway. A further strake is added later. We have reconstructed Kraka Fyr without its seventh and highest strake; on the trip to Anholt the ekstra strake could have functioned as a washboard and kept some of the water out of the boat.

In 2005 Ottar sails to Scotland, and the journey across the North Sea makes it possible to test the Viking navigation techniques on the open seas. The helmsman must keep the ship on course by watching the light and shadows in the sail, and by sensing the direction of the wind and waves towards the hull. A reconstruction of a solar compass, found in a Viking settlement in Greenland, was the crew's only navigational aid. When the experiment ends after 262 nautical miles, Ottar is only four degress off course, or around 10 nautical miles off the course read on the solar compass.

On the return journey, problems arise with the rudder. In Skagerrak there are gale-force winds with waves 3-4 metres high, and Ottar reaches an average speed of 9.8 knots. The high speed and the violent movements in the water wear the withy that holds the rudder onto the side of the ship. If Ottar is to continue to Skagen with its sail set to starboard, the steering oar will pull away from the ship's side, further straining the withy. Instead the sail is set to port side, to hold the rudder in place. On this course the ship sails to Norway, where the crew twist a new rudder withy of birch.
Withies are known from archaeological finds from the Viking Age. Experiences with sailing Ottar show us that a good with is strong 5-7 days at sea.

In 2007, The Sea Stallion from Glendalough sets sail for ireland in order to test the ship in the waters for which Skuldelev 2 was built to sail.
We will test the reconstruction, the ship's sailing capabilities, the crew's tasks and organisation. We quickly learn that a longship like Sea Stallion shapes its crew. Conditions on board require an almost military-like discipline, command structure and learned routines.

The experience of the trial voyage shows that there is a link between the ship's balance, its ability to beat to windward and the large crew. Skuldelev 2 was built for warrior transport, and every man on board also acted as 'live ballast'. On long stretches with steady wind wind Sea Stallion can be handled by a few people, but if the ship needs to beat to windward or be rowed, at least half the crew must take part. In strong winds and heavy seas, the crew places themselves on the luff side - the side of the ship facing the wind - to act as a counterweight to the sail and rigging and prevent Sea Stallion from capsizing. When changing course, the crew moves forward or aft, to force the boat around. The positioning of the crew is of great importance in how well the ship can tack and veer.