So I have been searching for a truly redundant solution, and then Cavendish (ovewr in the Canary Islands) hit the nail on the head, with an emergency rudder! So I have knocked together a diagram of such a solution, as below
A few observations (ie the theory)
- As it would only be for emergency use, you could probably get away with having to bolt the rudder blade onto the shaft (using wing-nuts) and put up with the extra drag.
I reckon a safety lanyard on the bottom is good insurance for when you are inserting the rudder from below.
I included a PVC "bearing tube" with glued on PVC collar to avoid any possibility of wear to the scupper tube... Far less an issue to fit a new bearing tube...
The collar at the top of the rudder shaft hold the rudder up, and its bottom (and the rudder shaft itself) could be waxed etc for minimal friction.
The amount of rudder shaft protruding at the top is entirely optional, and I could even envisage two tiller mounting holes, one at right angles for steering by lines (see below) if solo in the front seat of a TI, or pointing directly forward for steering by hand (in an AI or back seat of a TI)
To hook up for remote steering, I would do what I have on my external setup (which will no longer be needed once I fit this emergency rudder system). A bungee cord leads back to a block, and then links to a line going forward to a clamcleat by the seat, for adjustable tension (eg rudder will swing full right unless tension applied to the other line). Another line goes forward to another cleat. So steering direction relies on the tension applied to the latter cord. Easier to demonstrate than describe.
The practice)
I have made the rudder as per the drawing, using a piece of solid oak dowel (25mm od) for the rudder post. A local carpenter kindly cut 6mm slots in both ends of the dowel for the 6mm rudder blade to fit in (I plan on making a spare spare LOL). For free! See it pays to get out of big cities!
The clearance inside the scupper was not much, so I took a piece of fibreglass painter pole, and cut a 3mm vertical slot in it. This is now a nice firm push fit down the scupper as it compresses, and ensures that constant use of the emergency rudder will not disastrously wear through the scupper walls. I cut a piece of 12mm marine ply to fit over the compressed glass tube, leaving some tube above to support the rudder (which will probably have neutral bouyancy anyway, being all wood).
Next I cut another collar from the ply, with a hole to be a snug fit on the rudder post itself, and drilled a hole through both for a carbon rod I had lying around (might replace this with a thin SS bolt and wing-nut)
I am also adding a small ring on the top of the post, so a line can be dropped through the scupper, gathered up from outside, and then clipped on to the post, to pull it up through the scupper.
So now I have a rudder which will fit either an AI or a TI, and all I need to do now is add a tiller (more oak dowel, with a 6mm SS threaded rod inserted in the end, with a wing-nut to go on the back of the rudder post. Plus of course cover all my mistakes in safety orange paint!
The only limitation I envisage is that with the emergency rudder fitted, minimum water depth needs to be a bit over 2 feet, so removal of the rudder after the emergency will require some wading, a small price to pay for saving your bacon, IMO
The real beauty of this rudder is that a bunch of us could be out on an offshore excursion, and the emergency rudder could be handed over to whoever needs it. I know the chances of the steering becoming totally unservicable are very slim, but having been retrieved after drifting about 7 miles out to sea after a rudder line broke internally, and having broken two rudder pins on the one offshore outing to Broughton Island, I do not wish to get caught out again.
I can actually see it being good practice for every group venturing offshore to have one of these available within the fleet.
As I anticipate this emergency rudder being lent to someone else in the group on an offshore trip, I have written the instructions on the rudder blade. The bright yellow is to lessen the chance of losing it while transferring between kayaks. The tiller is offset about 30 degrees to port to give clearance to the skipper sitting forward of it.
In order to minimise any possible damage to the scupper wall, the 'glass painter pole section has a vertical split which allows it to fit firmly in the scupper, and act as the bearing for the rudder. The collar and tiller are held with wing-nuts for tool-free assembly.
A hole in the 'glass tube allows some water to escape through the scupper. The tube sits above its collar to act as a low friction vertical stop.
