Testing Norwegian "Goat Boats" | NTNU

[@sandrog2347]

Utmerket video, .. veldig informativ ..; Jeg skriver til deg fra Brasil, og den videoen økte min interesse for ... kanskje å lage et lignende skip ...- så langt har jeg bare gjort Vikingskipsmodeller så realistiske som mulig ... (Skuldelev 2) med et brettlignende system, har jeg noen tvil: ... hva er lengden og bredden på den båten? Og hvor mye er under vannlinjen? .. hvilket trevirke ble brukt? ... og tykkelsen på platene? .... Hvor lang tid tok det å bygge båten? .. Og de kobberspikerne med rebites ble kjøpt på et nettsted? ... og hvor mye veier den båten? ... Takk

[@TheMovieCreator]

I guess this is a little bit like comparing the Oselvar with the modern Strandebarmer. The Oselvar are made for rougher waters (open ocean), with hogde halser and the typical droplet hull-shape. It also have retained a very protected traditional design due to being a sanctioned regatta sailing class. The Strandebarmer was being made further inside the fjord, for nice conditions, and lacks the hogde halser despite older boats being otherwise quite similar to the Oselvar. Another thing is that it was adapted for mass-production in the 30s, and newer boats often lack the 3-board construction and droplet hull-shape of the older boats.

[@RolandLowhorn]

Years of study made a big difference the knowledge Pass to Next Generation

[@sandrog2347]

Venn, et spørsmål: hvor mye er den totale vekten til den båten?

[@Mile3500]

Shouldn't they be tested heeled over, the way it would be under sail?

[@modulfleirfall]

So you think 10 seconds of video from the test IS the whole test? What are you trying to point out? That you are stupid? Besides, it WAS heeled over.

[@ttyrtttyy]

Congratulations

[@georgejohnson1498]

As a proud half-Nmorwegian, what I am am interested in how the Vikings knew that the bottom strake should be concave for greater efficiency through the water? That is at least a thousand years before “CAD” and computer modelling .. I have rowed a fearing, in the 1960s, and by goodness it was a rocket compared to a normal flat strake rowing boat. of similar size.

[@carmelpule6954]

The interesting issue about a boat is that it operates in between two mediums, air and water. For a craft which operates in one medium as a fish ( submarine) or a bird ( plane) the shape for the least resistance is normally that of of a teardrop where the font is not so pointed, but the run aft is longer to permit the sideway moved or displaced medium return back to fill the space or trough through which the craft moved. With boats it is much more complex as the surface curve changes with speed and a speeding boat tends to create a hill of its own making under the bows and then a hollow under the main body and then the wave peaks again at about 3/4 length near the back end. This in a displacement hull is normally the economical highest speed. As far as the front end is concerned its duty is to cut a trough or a furrow through the water through which the boat can go through. This means that water particles have to be thrown or accelerated sideways or down under the boat. Force is necessary to accelerate sideways the water particles and the sideways acceleration depends on the bow angle where a narrow bow half angle will cause less acceleration . This is the reason why catamarans and trimarans are faster than single hulls where the bow penetrating angle is low so the side acceleration of water particles is small. With a buff bow as in lifeboats, the requirement is to carry a load and to lift the bows quickly and with an aft following wave the bows will not dig into the water to avoid broaching. With observation our forefather could feel all this and they designed accordingly. My own forefathers were traditional boat builders in the Med and my own uncle used to tell me all about how he felt a need for a particular part of the boat and the reason for the selection. Education does not mean going to school and learning knowledge from books. Learning can be achieved by anyone and in the old days they connected well with all they did and nature itself. Some years ago I lifted the lines of a boat that my uncle made over 100 years ago an compared them with a modern CAD design and I was not surprised that they were not much different . Well I can understand this as evolution of fish and birds did not need cad to finish up with the shape they have and what is more , a bird or a fish can adjust automatically to the required variable speed condition. Just look at a hawk or an eagle how it changes shape while it is soaring and attacking its prey, the shape changes and even long distant fliers like the albatross is far from the shape of an own which is not really a long distance flier but a night flier which needs to be quiet to fly at night. So the shape of the part that you are referring to was evolved through the intelligent of humans observing in silence the manner in which nature works. The garboard needed to be concave so that the acceleration of waterparticles in a lateral direction would be small enough and this also explains why they have the frame VEE near the keel rather than flat as with a flat bottom on movement it would require to accelerate the water particles under the b oat which tend to LIFT the boat which is not a good thing in a rowing boat as power and energy needs to be used very economically. Congratulations for your good observation.