Currach oars

I appreciate that currachs are light

Not always. In the area around Mweenish island where Galway hookers are built, the currachs are made the same way as the hookers. Carvel build with good old-fashioned caulking, 3/4" larch strakes, 1 1/2" oak frames. A 15 foot boat could weigh a quarter of a ton.

Despite the extra weight, the timber ones still behave in a very similar fashion to the lighter currachs. They're less tippy (one could stand on a gunwale and it wouldn't drop much) and although not as quick off the mark in a straight line, they spin beautifully and their weight gives them a useful momentum in a chop.
 
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