I've been working my brain way too hard onboard Medallia today, trying to think my way out of a performance hindering problem with my wind data.

Mid morning I was rudely awakened from a snooze by the pilot crash gybing the boat which is never a good way to wake up. Once I'd clambered on deck and got us back on our feet again, checking for damage I engaged the pilot again only for it to dive off towards another gybe. A quick check revealed that the wind data was absolute rubbish so I set us up to steer to the compass and wandered to the mast to look at my wand. I'm still not really sure what has happened. From deck level with the binoculars it looks like a cup is missing of the speed sensor but neither the cups or the wand are rotating at all, they are both stuck solid. Very strange and definetly not the conditions to go aloft and check it out.
 

This is bad news as my second wind wand fell off during the first big front we encountered just three days after the start so I now have no wind data coming from the top of the mast. The wind data is absolutely crucial to my performance. Sure I can sail safely without it, being conservative with my sail set up and using my powers of observation and the barometer to get a sense for wind strength and direction. But to perform without this data is hard. It's the nuanced changes that make a difference, particularly the analysis of my polars - that is how well I am sailing against my theoretical best performance in any given wind conditions. Without this point of reference I would be forced into guestimating whether I was sailing fast or not which can only be detrimental to performance.

I must admit to being more than crushed by this eventuality. I guess there is a part of me that has been waiting for the hammer to fall. I have been doing so well and almost thinking I am getting away with something. There is always a bit of me waiting for the big banana skin to trip me up and send me flying. So I had a little pity party. A moment of wallowing, of lamenting for what I now don't have and mentally watching the rest of the fleet sail past me as I waddle home with reefs in and a storm jib. But there is only so much of you can take when you are alone, because there isn't anyone else to make things different. So after a cup of tea and something to eat I put my big girl pants on and went looking for a solution.

I have an emergency wind wand, which is mounted on the pushpit at deck level. The problem with this wand is that it can only be used in conjunction with my spare pilot. The problem with my spare pilot is that it is not nearly as reliable or a clever as my main pilot so I really do not want to use it unless I have to. I sat down and worked through my options then decided what I needed to do was stick with the main pilot driving on compass mode, and try and get the wind data into the computer some how to help me with performance and navigation. The rest I will have to do by feel - embrace the Jedi within. I know the boat pretty well by now and I spent three years sailing mini 650s with no onboard computers to help so I'm just going to have to try.

Step one to install the wand and get the feed into the computer was surprisingly easy. Moving around a few wires and reconfiguring the Com ports into my navigation software. Step two has been harder - that is to try and get the data to relate to my own points of reference. The problem being all of my datums are from a mast head unit and I am now operating at deck level, where the apparent wind is less and the wind wand itself sticking out at a jaunty angle.

I spent a while googling the difference in wind strength relative to height above sea level and found a rather complicated formula to work it out. Spent half an hour trying to remember how to solve a quadratic equation from my school days, have managed to work out a number that seems to be about right and have altered the calibration of the deck level wand to read what I think it might at mast height. Next I have played around with the wind angle offset to try and get the apparent wind angle about right. With these numbers as a base line I have then spent the rest of the day, sort of reverse engineering the wind data to something that is vaguely helpful. Every time the wind has increased or wind angle changed I have gone on deck, looked at the sea, the waves and the trim of the sails and made an evaluation as to whether the wind data fits what I am seeing. All day I have nudged the wind angle this way and that, changed the windspeed coefficient by one or two and finally I think I have something that might be useful. The only downside being when I gybe tomorrow, I will need to transfer the wand to the other side of the boat and do the whole process again.

Of course it's not perfect, when we surf down waves the wind angle goes completely out as the apparent wind at deck level is very different to that at the top of the mast, for this I have dampened down the wind data and set up my computer to read from averages to help me with my decision making. The data is not absolute but at least I now have a point of relativity to work from and I am going to need to rebuild my knowledge bank around reefing, sail changes and performance to suit this new data.

I'm feeling a lot better about life now. It's still far from ideal and I am completely gutted that this has happened. But it happened and it won't keep me down. I have a good feel for Medallia and I need to use that feeling to help me evaluate whether my data is accurate and make good decisions. This will undoubtedly mean making some conservative calls on sail choices in the short term which will be a change in mode for me as I have been deliberately pushing the boundaries in the last two weeks. But there is still a lot of the race to go. I need to revert to learning mode, get comfortable with my numbers again then I can find the opportunity once again to push.

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