The Mk II rudder

The class adopted a new, improved rudder design in the year 2000, with the old design grandfathered. The new design, drawn by David Thomas himself, is generally considered a marked improvement on the old. It’s a little deeper and has a different profile that gives greater feel and ‘grip’, especially when close-reaching under spinnaker in a breeze. You can download the plans below. Peter Duggan built one for his boat, Fly – and he talks about it here. If you don’t want to build one yourself, a number of people have bought them from Milanes Foils and other sources. 

2 Comments

KPALFREEMAN · March 10, 2011 at 4:19 pm

Just a word for those who still have the old “plank”. I have found in fleet racing, in most conditions, it is the same speed as the new rudder, so no need to race out and spend £800 plus.

The Mk II rudder certainly looks very speedy. Apart from the looks, it is about 150mm (6 inches) deeper in the water. Presumably that means a little more drag, probably offset by the “boeing dreamliner” shape.
The key advantage is close reaching with the kite up. As the boat heels, less and less of the rudder is in the water and then the extra 6 inches can represent 10 – 20% more area left to bite and instead of rounding up in a gust the spi sheet can be eased (a lot !) and helmsman can get the boat to bear away and back under control.
None of that unnerving feeling when the tiller goes completely slack and you know you have lost control.

Of course any original Mk I rudders are now a bit long in the tooth, but if you are using one and it’s in good condition you won’t lose out in speed in light to moderate conditions.

Fabio · March 28, 2013 at 8:46 am

Hi all,
together with a friend I recently purchased the “Runaway”. This boat was at some stage fitted with a stern extension, and because of this, the rudder had to be changed as the old outboard type did not fit any longer.
We were thinking of selling it. Would anyone know whether people may need it as spare part? Would anyone be interested?
Thanks for advice,
Fabio

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