Let's face it, things rarely break down when you're out there just lolly gaging around
I think having a spare paddle is a great idea for all the reasons being discussed here. If I ever lost rudder control I'd want something to replace it with quickly and easily! Using a kayak paddle as a rudder though is difficult because it has a curved blade.
I put together a paddle from an old canoe paddle which has a flat blade
and much easier to use. It measures 6' long
and has a straight, "T" handle
made from 3/4" pvc fittings . I also filled the aluminium tubes with spray foam insulation so it will float. I've used it on many occasions, in strong winds and without an oarlock. It's the only paddle on my boat. Other than the shape of the blade, I think what makes this work as a rudder is it's length
. I can easily hold it against the side of the boat with enough of the blade far enough back in the water to successfully steer with.
In the Inter coastal Waterway we have shallow areas called "The Flats". Depending on the tide, there can be only 1-2 ft of water out there, or sometimes none at all. From a distance these areas are pretty easy to spot when you see Egrets walking around
but sometimes just a few yards away, there can be just enough water for my TI to sail over - (If I have nothing sticking down).
If things start to get skinny I'll keep a close eye on my dagger board. When it begins to nudge forward, I'll uncleat my rudder's down line and move myself forward to get some weight off the stern. If my dagger board goes forward any more, I'll slide it completely up inside the boat and pull my rudder completely out of the water. I'll then grab my paddle, move back to my seat and keep sailing - but now I'm using my paddle, not the rudder, to control the direction of my boat. Quick and easy