“I did some speed test this morning….smooth sea state, F3 wind on the beam:”
1000 rpm – 3.2 knots
1200 rpm – 3.5 knots (+0.3)
1400 rpm – 4.1 knots (+0.6)
1600 rpm – 4.7 knots (+0.6)
1800 rpm – 5.3 knots (+0.6)
2000 rpm – 5.8 knots (+0.5)
2200 rpm – 6.2 knots (+0.4)
2400 rpm – 6.6 knots (+0.4)
2600 rpm – 6.9 knots (+0.3)
2800 rpm – 7.2 knots (+0.3)
3000 rpm – 7.3 knots (+0.1)
3200 rpm – 7.4 knots (+0.1)
3400 rpm – 7.5 knots (+0.1)
“It seems to work very well and it’s a great relief to have stopped the prop shaft spinning under sail. The reduced drag is noticeable I would say, with an appreciable increase in hull speed particularly in lighter winds, and a smoother carved turn through the water when tacking. Happy!”
