The Taming of the Screw

If I'm honest, the science behind the fine tuning of propellers has always been a bit beyond me. I remember on our last boat Silurian there was a lot of cursing and filing down, refitting and more cursing to do with the propeller. This time, I'm determined to get my head around it a bit better and it seems the hybrid engine might provide that opportunity. One of the main things which put us off the hybrid engine in the beginning was that we understood (wrongly) that in order to generate electricity the propeller would need to be in a permanently fixed position thus slowing the boat down. This was immediately dismissed as a no-no, just not something a Rogers would willingly sign up to! After Graeme Hawksley's visit from Hybrid Marine it became apparent that we could actually fit a feathering prop (one that slips into a streamlined position when the boat is sailing forward) which could be forced into a generating position (non streamlined) when we wanted to generate electricity from the prop - ie not during a race. After a little research it seems that the prop for the job is an 18" Featherstream propeller made by a local company called Darglow Marine. The exciting news is that Darglow Marine are keen to use Calypso as a test bed for props working with hybrid engines - I can feel a deal more cursing, filing and refitting ahead! At least we'll have the experts helping us.

To hybrid or not to hybrid?

Not long ago we all sat down around Jeremy and Fiona's kitchen table and did a good job of convincing ourselves that we didn't want a hybrid engine. There would be constant drag with the prop spinning we thought, and anyway, the brief was to keep things simple. Then Graeme Hawksley from Hybrid Marine came into the yard and quietly but very convincingly explained why we definitely do want a hybrid engine. He allayed our fears about a constantly spinning prop (we can feather it when it's not needed which won't affect performance when racing) and we can integrate it with the solar and wind systems, helping to keep things simple. The truth is, electric is way things are going in the car industry and it's going to be true of boating too, so we might as well lead the way!