Congrats to Bora, who is the first guy to break the 30 knot barrier. Oh and in the process he absolutely smashed the old record. Full details are on his blog.

I have the track file and this claim is 100% legit.

The next question is: how long until Doug Lord starts another thread on sailing anarchy? His usual lead time is 2 days behind the rest of the world.

Ok it’s coming to the end of the pre-season prep with the first real race of the season underway this weekend. With that in mind, (and the fact that the moth blogging has all but dried up lately) I thought that I should check in on how I am progressing against my to do list.

• Getting my ass out of the workshop and onto the water. – Despite my best efforts I have had four short sails, and all of then have ended early, 4 breakages to fix this week – FAIL
• Getting fit and loosing 10 kilos. – Weight loss is progressing, I am now consistently sub 90.5 KG and have gone sub 90 KG. Fitness needs work – IN PROGRESS
• Grow some cahones in 15 knots plus – Progressing. The real test would have been downwind last week but the boat broke – IN PROGRESS
• Learning how foil gybe and nail it every time – FAIL
• Turning my OK tacks in to consistently good tacks – FAIL
• Build some new spreaders with the correct geometry – DONE, total cost $7.50
• Get my foil’s “finished” – DONE
• Find another 10 knots of boat speed. – IN PROGRESS

After realising last week that my numbers were absolutely wrong I approached Luka and called in a favour.

Thursday night became setup night and we went over everything on the boat and when I say everything I mean everything.

Saturday rolls around and it was time to head out a few hours before the race with John Gilmour. John’s boat is identical to mine except he is running a Fastacraft gen 2 main foil whereas I am running my own.

Well the boat was transformed. Sailing from the shore it wasn’t quite right and it needed some rudder trimming but after that it felt like a rocket ship (but probably isn’t … but until Dave or Luka crushes me, I can live in hope). I was just as fast or faster than John in any direction although to be fair he was having a couple of issues himself.

I was out for an hour and a half or so then my control rod broke. Bugger. I headed in and bolted home to fix it. I made it back just in time to be 30 secs late for the start.

The breeze had kicked up at this point to 20kts in the gusts (according to the airport). I have altered my upwind technique this season and I was much faster upwind. Phil who started on time was not pulling away and I caught and passed a 16″ skiff and Bruce Gault in his 16″ foiler.

Then the rudder exploded. I went to tack and when I threw the rudder over the tiller wasn’t attached to the top of the foil. After an hour drifting ashore to the river club I walked home then got the trailer and recovered myself back home.

So the setup has been sorted and it’s all up to me now. Hopefully I have used all up my bad luck ready for the season start proper next week, once I put it all back together again. But I am still smiling.

I went for a sail on Saturday and my boat was still flying out. At one point I was sitting at the front wing bar, with full CB flap up, and full rudder flap down, and she still keeps on coming out. Not good.

So what is the problem? My current theory is it is being caused by a combination of two things: 1) too much AOA, and 2) flap twist.

When I put my foil in the boat initially, I had run out of adjustment in the case fore and aft and I felt I was running a bit bow-up, so I thought I should build some more AOA into the foil itself, to get the bow down level, and if it didn’t work I can always drill a new hole and reduce the angle and / or move forwards in the boat whilst sailing.

I measured the foil tonight and it looks like I am running 3.8 degrees on the foil … hmmm that seems a bit excessive so I ran some some numbers to check.

For this model I am assuming that my all up weight needing to be lifted is 125kg. I am also assuming a 30% flap, and that I am effectively loosing 50% of that through flap twist.

So at 15 knots, there is already no situation where the wand can bring the boat down, and even if my flap didn’t twist, I would only have 35kg to play with at 15 knots of boat speed. So what happens if the boat was at 25 knots.

So the numbers have confirmed that I am running too much AOA, so what are the numbers if I reduce it to say 2 degrees.

All this number crunching explains a number of actual things I have seen on the boat.

1. Since I have foiled with the latest AOA, the boat can’t stay in the water, regardless what the wand does and this is confirmed by the numbers.

2. When I was foiling before (at the nationals and after) the boat was OK most of the time, but sometimes the wand would just float in the air and do nothing … This has also been confirmed by the numbers, as when the speed was over ~18 knots the flap starts to get a bit marginal on paper.

So the solutions appear to be to reduce the AOA to +2 degrees and stiffen the flap and make it a bit bigger, so it doesn’t have a 50% twisting loss.

Then at 15 knots of boat speed, with a flap up level the total lift is 120 kg. Then at 25 knots, with the flap 5 degrees up, the lift is 125 kg, the same number as my assumed all up sailing weight.

I think that co-incidence is telling me something. It also shows that there is definitely an AOA sweet spot, and 3.8 degrees isn’t it

I was poking through the moths for sale site tonight and was quite surprised how low the price of some of these boats is getting here are some of the current boats for sale:

1. Bladerider #1 – $ 6,900 AUD
2. On the prowl – Mk1 Prowler with gen 2 foils $7250 AUD

Both those are cheaper than the cost of my home build …

3. Production Bladerider RX #4 $9,950 AUD (needs work apparently)

4. The current Australian Champion X8 was $14,500 AUD, but it’s gone, resprayed and looking like new.

So if you are thinking about getting into the class, there are a few bargains around now, all with the potential to be just as quick as any other boat with a bit of elbow grease and some TLC.

At this rate it won’t be worth home building anymore, it will just be cheaper and easier to buy, repair, respray and update a good second hander, especially when you are getting a pre-preg hull.