On the First Northern European Sailing and Cargo Vessels (Knorr or Knarr type)
This paper is, in a way, a complement to an earlier paper by the same author, “The Nydam Family – On the Last Northern European Large Rowing Vessels.” Together, both papers address a monumental shift from human- to sail-powered ships in Northern Europe that took place roughly around the change from the first to the second millennium AD.
A number of old wrecks of representatives of those early sail-powered cargo vessels – commonly referred to as the “Knarr” type (in German: “Knorr” type) – have been found and, in some cases, raised in the coastal waters of Norway, Denmark, Sweden and Germany as listed in figure/table 1. The one wreck that has thus far yielded by far the most information is the “Skuldelev 1,” which had been built around 1040 AD and was an ocean-going cargo ship, about 16 meters long and 4.8 meters wide. A limited reconstruction of the ship from the about 60% of the structure that has been found and preserved is on display at the Viking Ship Museum at Roskilde, Denmark.
As in the case of the earlier work, this paper focuses on technical and, to a lesser degree, operational aspects of these ships, both of which tend to be rather neglected in the available literature which typically concentrates on archeological and historical aspects.
After an introduction to the subject matter at hand and similar to the approach in the earlier paper on rowing vessels, this paper first develops a design or virtual model as it were of a ship very much like the Skuldelev 1. This model is referred to as the “Skuldelev 1 / 2019.” Engineering judgement is used to fill some of the gaps of knowledge left by the incomplete wreckage. For example, no parts belonging to the ship’s mast and yard had been found. Therefore, this paper uses some empirical formulas to come up with estimates for their likely dimensions.
In addition to the ship’s geometry, some operational issues are discussed as well. For example, the extremely harsh living conditions for the crew during voyages that lasted up to several weeks without going ashore – no cover from the elements and no facilities to heat up food – are highlighted.
The description of the design/virtual model is of interest all by itself in that it provides much more insight into what a Knarr type ship must have looked like and how it must have been operated than the display at Roskilde can or the existing literature do. However, the paper then goes on and describes, at a relatively high level, some hydrostatic, stability- and strength-related analyses conducted by the author whose results shed additional light on the Skuldelev 1 / 2019 in particular and the Knarr-type in general.
One key result is that the Skuldelev 1 / 2019’s stability must have been precarious – mostly due to the ship’s limited freeboard and together with the fact that it didn’t feature any watertight decks and, therefore, in heavy seas, water could easily spill into the ship’s hull: Some time would have to elapse before cargo ships featuring decks with hatches did evolve. On the other hand, the Skuldelev 1 / 2019’s structural configuration and cross-sections appear to have been such that stresses did not exceed moderate values in all but truly extreme and extremely rare load cases. In other words, the design appears to have been structurally robust.
The paper ends with an appendix with a list of references as well as well as all the figures and tables referred to in the paper.