Investigation 11

A personal account – Paul Constantine

 

A Rudder Solution?

The story of the rudder is complex. Basically, it is to be fixed close to the stern of the ship on the Steerboard/Steuerbord – side, that became known as the Starboard side, as a result of this name. To understand what follows, in depth, you should first read Digging Deeper – Great Rudder Mystery this website.

Having explored the many problems associated with the rudder, in the above article, it was still imperative to settle on a probable design. The only real guidance could come from the Nydam Pine ship rudder (see picture, Rudder Mystery) as this had been a contributing starting point for the actual Nydam Oak ship's rudder, whose original rudder was so badly damaged that it could not be used. The reconstructed one in Schleswig-Holstein attached to the actual craft has been developed from the Oak ship's drawings and dimensions, blended with the the Pine rudder's form, but clearly it was not rigged in a functioning manner; it was illustrative. If the findings of the Sutton ship excavation were to be recognised, the system to be used should probably not use a boss/button, as seen on most Scandinavian craft, or be secured by piercing holes through the lower hull planking needed for the button.

Vorså

So, what did the builders of the modern reproduction Nydam Tvei use on their fully operational craft? The answer, thanks to our good friend Ole Brixen-Sondergaard who was part of the building crew, was that whilst they used the Nydam rudder form they also used the basic pattern of the rudder-support system from the Vorså wreck. The system did not require a button. The Vorså rudder was recovered in the Kattegat in 1958 near to the town of Vorså on the north-eastern corner of Jutland. It was given to a museum in Frederikshaven. Referring to it as a (steering) oar, the almost legendary Scandinavian boat expert, Ole Crumlin-Pedersen, described it in this way:

‘The oar is of oak, very slender and well-formed. The blade measures 1.92 metres, and the total length is 2.80 metres. The width of the blade increases from 0.175 m. at the top to 0.375 m. at the bottom, where the aft edge forms a little "heel", while its thickness decreases from 10 cms. to 1.5 cms. The sections show that the oar blade is asymmetrically formed, the side towards the ship being almost flat while the other side is curved to a greater or less degree. The fore edge is sharp, while the aft edge is fairly square-cut. At the top there are two oval holes for attachment of the rudder bar, and at the thickest point there is a hole of 4.7 cms. diameter for the withe in which the steering oar was hung.’

And

‘Various modes of suspension have been proposed to explain the many holes and marks of wear on this oar. In the case of the Vorså oar the two holes for the rudder bar are explained by the fact that the oar could be used in two positions, almost vertical during deep-water sailing, or, for shallow-water sailing, turned around the withe into an oblique position where the lower edge of the oar came level with the keel. This feature suggests that the oar belonged to a merchant ship which could only with difficulty be manoevred by means of oars alone. The asymmetrical section resulted in the oar lying close in to the ship, so that wear on the withe in which it hung would be minimal.’

The steering oar was thought to be Norwegian in origin and dated 9 – 12C. Viking ships used withies instead of rope to control the movement of the steering oar due to flexibility and durability, Hence his reference to ‘withe’. This oar is later than the Anglo-Saxon period of the Sutton Hoo ship and backdating knowledge is rather unsafe, but the system used to suspend this oar covers the design requirements, so it is difficult to ignore it. Crumlin-Pedersen suggests that the length of the oar at 2.8m (just over 9ft) makes it more suited to a merchant ship, which is quite likely. Side-steering oars of this type were in use from centuries BC, (eg. Kyrenia ship about 300BC) right up to the medieval era. Steering oars discovered along England’s east coast in the Southwold Museum, carbon date from 850 – 950AD are over 4m (more than 13ft) tall and claimed to be the longest ‘Viking’ rudders ever found.                                                                                         Southwold rudders

The suspension system illustrated

The basic illustrations usually referred to when describing this Vorså  system are attributed to Harald Akerman published 1941. Just the drawings are reproduced in Volume 1, page 411, but can easily be missed. On the original page they appear to be most unpromising, but closer examination shows that diagram b) supports the rudder without piercing the side of the ship in the usual manner.

Akerman's original page

These are some of the salient points to bear in mind when looking at the drawings:

  • The main diagram, (left) shows a very sophisticated bottom end to the rudder, enhanced to maximise hydrodynamic flow (see Digging Deeper Rudder). This shaping for faster sailing ships was probably not in use for the slower rowed craft of Nydam/Sutton Hoo, so it can be ignored. The diagrams also shows the ‘tied’-rib securing system, which is not relevant to the Sutton ship (see Digging Deeper Rudder).
  • The two diagrams a & a illustrate the same system which uses a withy to secure the steering oar against a wooden rubbing strip secured to the ship’s side. The withy pierces the rubbing strip and the hull. This is therefore, a system that cannot be used if we accept the findings of the excavators of the Sutton Hoo ship.
  • Diagram ‘b’ uses a very different system. A rudder support timber is shaped to hook under the overlapping edges of the clinker planks to lock it in place. It could also hook over the gunwale to lock under the shaped rib 24 on the Sutton Hoo ship. The support then projects outwards away from the ship and has a secondary downwards projection against which the rudder is fixed. The whole device could be secured in place to stop rearwards movement on the tapering hull.
  • The fixing withy/rope pierces the outer projection, but not the side of the ship. It is lead around and up over the gunwale to be secured inside the ship.                                                                 

  Rudder fore & aft alignment                                                                                                              Diagram b

One great advantage of this system is that it can take account of the angle of the ship’s side when viewed from above. A rudder should align with the keel, straight forwards, when in its ‘neutral’ position. If it is turned to left or right the disturbed water flow will steer the ship to one side or another. A rudder pressing directly against a horizontal rubbing rail on the ship’s side would take the angle of that rail, if the rail was not wedge shaped to be wider at the back, but was just a flat rail. Pressing the steering oar flat against the starboard-side planks would mean it would be steering to the left (Port). This steering oar fixed at guwale level, is shown in Das Nydambåden, page 30. The boss system can restrict universal movement, needed to allow for this effect.

It is of great interest to see that the description of the blade of the steering oar indicates that it was hydrodynamically shaped in cross-section, to provide lift away from the ship’s side (see Digging Deeper). This would mean that the top section would be naturally inclined to press inwards towards the helmsperson and against the ship’s side. This movement can be seen in a photograph in Das Nydambådenon page 74 of Honour of Steding, a German reproduction of the Nydam ship launched in 1934 by Abeking & Rasmussen.

Picture of rudder-lift away from the ship & control rope, from Das Nydambåden

The vertical strip on the inside of the Nydam rudder may simply have been a rubbing strip to protect the planking if the rudder came into contact with the ship.

 

The story of the German reconstruction.

In 1934 A National Socialist Culture organisation in Rastede commissioned a full-size copy of the Nydam ship for a film called Eternal Forest. It was fitted with dragon heads and a mast to make it appear ‘Viking’. It was named Honour of Steding after a historic National Socialist peasant’s sanctuary near Bremen, that was crushed in 1234AD. A film of the launch shows the ship’s maiden voyage on the River Weser near Bremen. The helm can be seen urging the rowers by calling and waving his arms in time with the oar strokes. The steering oar is secured by rope through the gunwale/sheer-strake and has two restraining ropes, attached from a central hole in the blade up to the gunwale fore and aft.

Whilst this film had been known to the constructors of the Anglo-Saxon ship it was not studied in detail until December 2025. A visitor, Hanneke Boon viewing the video immediately remarked on the effectiveness of the system used on this ship. Hanneke Boon operates James Wharram Designs and has a lifetime’s experience of studying and cataloguing ethnic craft worldwide; designing, constructing and sailing such craft. She has sailed round the world and criss-crossed the Atlantic and Pacific oceans. She has a ‘library’ of photographs and detailed drawings of steering systems. She has sailing connections across the globe and an enduring interest in historic constructions and sailing techniques. Side rudders are commonly used today and she has vast experience of using them.

She explained how in the film, the helm was able to steer the boat conventionally with the oar, often using a single hand, but also had the added facility to ‘row’ the stern around in either direction, if needed. She said that this was a very useful ability that should possibly be retained. She has formidable sailing experience with various systems like this in craft from 14-63ft, whereas the project builders currently had little or no experience.

She also explained that securing the steering oar tightly at gunwale level with a broad leather strap, introduces a great deal of friction into the steering and restricts the ability to lift the oar at the stern, if required. She suggested the gunwale securing rope might form a figure-8 around the oar to both secure it and also allow the more flexible movement of rotating the shaft within the binding. She advised that the system would function on rowed craft usually travelling little faster than 3-4 knots, but possibly not be as efficient on sailing craft at potentially greater speeds. It is clear in the film that the ship exceeds such slow speeds, but the steering is still effective. In the film there is a suggestion of a ‘thrust’ block outside of the sheer, astern of the steering oar.

The Archaeological Evidence.

When the form of the ribs at 24 & 25 is examined, it is possible to see that the expanded tops could have been to strengthen the strake where holes were bored to allow the attaching ropes to pass through. The oar would not have been secured through planking alone. The photograph by Phillips, with an accompanying diagram Vol 1 406-407, appear to show that they could have overlapped the sheer-strake instead of stopping below it. Holes and trenails did not show in the impression in the soil of the excavation. This is an operational system.

The reasons for strongly considering this system are:

  • It has been shown to work
  • It fits the existing archaeological evidence
  • It is simple, requiring no other complex support structure
  • It may be supported by the previous, Roman gunwale-attachment-only system
  • It does not need the sailing-ship, button system used 200 years later by Scandinavian seafarers
  • The reconstruction is an experimental archaeology project and this is a justifiable starting point to try to understand the likely decisions taken by the original constructors.

oooOOooo

 

Medieval Town Seals

            Illustrating the side rudder being used on later,

          larger craft. The rudder image left,

appears to be on the port side,

but this is the ‘negative’.

When used,the image will be reversed.

The Dunwich seal has already been stamped. 

Dover (left)                                                  Dunwich (right)