admin Date , October 5, 2025 Sailing Previous Blog Storm Amy Last Comments (0)
What we have been asked to do is find out how fast the Whaly 455 will go at different engine powers. This is the story.
It was a quiet Wednesday Morning. The sky was overcast and the Temp was 15C. There wasn't much stream on the River and the wind was very light at less than 5mph. In the first set of test Peter and I were in the boat in subsequent tests Paul and I were in the boat. The weight was about the same.
The idea of the Test was to test the Power and speed of the e-Propulsion engine. So we had a fully charged battery and went up and down the river ar more or less the same Watt output on the engine determining the speed with the onboard sensor. We could have used the GPS to record the speed more precisely.
So one eye on the boat speed the other looking out for some of the sailing boats on the water.
The speed of the boat depends on many factors - even the temperature has an effect. Obvious things are the weight of the crew, hull shape and weather conditions. We know the Whaly responds to the Wind so we tried to do all the tests on non windy days
Whilst we tested the boat out, other members tried to find the wind on a calm day.
We did several different runs at a variety of different power and recorded the speed. Here are the results. As more and power is used so less and less of this is turned into speed. The graph is exponential in nature, so for each increase in the power used there is a decreasing amount added to the speed. This is true for petrol engines as well as the electric. There was a spread in the data of travelling up and down stream ( down was mostly faster.) The most efficient was at the lowest power outputs.
