Hey Florian,

I aborted the last two runs as the conditions were just plain messy. I thought we might have been in for a big day as I saw a gust to 29 knots on the course when we first set up the weather station. The trouble was that we also saw low's around 16-17. The direction was also swinging way into the West i.e. making the course more downwind. When we got the wing up at the top of the course I noted that it simply didn't feel that windy. The odd gust would come through quite strong though... so we went for it. The start went OK although the acceleration wasn't great. A good gust came through and I was very keen to get the large, retractable rear skeg up quickly. The pull-up line is near the mainsheet and a slight fumble on my part caused the wing to be eased as the skeg came up. I need one more hand some times! Anyway, this slowed the acceleration and hence the build up in Apparent wind speed. When I turned down the course... the apparent wind didn't come with me. I put this down to the wind dropping off and the westerly component... and the lack of boatspeed during the run in. VSR2 sagged down and I aborted the run stopping just in front of the timing hut.

We lowered the wing and sat and watched the wind for a couple of hours. It was a dodgy day.

For some reason Helena's phone wouldn't send the 'tweets' to keep you all updated. She was trying.

Conditions weren't that good but we decided to try again. The second run just simply didn't get going at all. The boat felt heavy... but then the wind wasn't very strong. I aborted again in front of the timing hut.

It was disappointing. Once again we rode the emotional roller-coaster of 'today could be the day... not it isn't'. We washed VSR2 down as always and went and had a beer.

No breakages, no issues, no exciting speeds. We had made improvements to the data acquisitin and comms. but that is about it.

Today is very flat. Tomorrow might deliver.

Yes, VSR2 is ready and at full capacity. All the little aero gadgets are on. We're going for it now.

Cheers, Paul.

 Hi SL.

The fuselage is angled at around 26 degrees from what I remember. I would have to double check as the actual centerline of the boat is more determined by the chord of the foil and the leeway angle than the direction of the floats.

When designing the aeedynamic package of this boat we took into account the wind shear and twist of the location. We went out onto the course and measured the wind shear from ground level up to around 20'. It turned out to be very close to predicted levels found in text books (Whadya know?).

So as we get lower down... especially at the float level, we need to orientate everything for tighter apparent wind angles(AWA).

Funny thing about that little 'yaw string' wind indicator in front of the cockpit... I forget it every time. I need to climb/slide up the bow to get in the cockpit so I remove the indicator every time. It has a small drilled hole which it is pressed into. I keep the indicator stowed in the cables in the cockpit when it is not in place. I remind myself every time to put it in place as it is a key indicator as mentioned. Even when I do remember to put it in place... I forget to look at it. It's right in my face too. I don't know why I struggle with this. Now I get Alex in the RIB to remind me as part of our double-check-list once I am seated in the boat and being 'lowered' out onto the course. Practice will improve all this. So, the masthead video you have is from a run where the indicator is not present. It was in the last 46.2 knot peak average run and I could see it from the masthead.

We now also have the onboard wind data being recorded. You would think it was easy. Getting real accurate wind off a boat is actually extremely hard. We have all sorts of interference issues with the amount of GPS, vhf, intercomm, wireless etc stuff bouncing around the cockpit. I think we have it resolved now.

In reply to one of your earlier posts, a huge amount of work has been done on the aero modelling and general VPP (Velocity prediction program) for this boat. It is our second boat. The first boat's VPP provided a great starter platform for this boat. I am very confident in the work done by AEROTROPE in modelling the overall performance of VSR2. We chose to include numbers bordering on the pessimistic to include in the VPP. I would rather the boat be likely to overperform than the other option.

I have often questioned Chris (AEROTROPE) about how much difference it makes to performance if the fuselage isn't aligned... and I'm often disappointed by the low overall effect of it in comparison to the hydrodynamic issues.

The wing angle is of course more critical. Obviously if we aren't achieving our polars i.e. 60+ in 26 knots then we need to reconsider how the boat should be sheeted. This is pretty basic stuff on any sailing boat regardless of speed. We do still use tell-tales you know;) The fact is that once I am properly hooked into the wind and have turned away down the course, the acceleration comes with each little bit of sheet pulled in. The tell tales are quickly referenced during runs as they are always refenced during the strart up phase. AWA changes quite quickly from rest whilst AWS (apparent wind strength) builds slowly. As the AWA moves forward of 45 degrees the balance begins to go the other way. From the cockpit I pretty much use tell-tales and the feel of the boat i.e. if I sheet in more, do I accelerate... if not, check tell-tales and ease a bit. Like I said, pretty normal stuff.

I agree that there are potentially some losses and refinement that could currently be made here... but on the other hand... this is not the reason we are stuck in the low 50's. We shouldn't start setting the boat up just for this speed. There are far bigger issues and we should remain focused on 60 knots. If we thought all these problems were causing a mid-high speed hump then I would be more concerned. Sailing in more wind has shown us that it is not a power thing (Yes, we know that higher TWS leads to bigger AWA's for the same speed). The aspects you have raised have all been discussed in detail. Once we have finished sailing on the water... the data gets processed and sent back to Malcolm and Chris who then proceed to go sailing in the VPP to see how things match up.

I haven't checked your maths... but I am confident they have checked theirs... and then cross-checked each others. We encourage our team to find faults in each others reasoning or calcs. We do it in a healthy and constructive way.

If you like I can perhaps send any further queries you might have onto Malc who can be more specific on the maths.

Cheers, Paul

 Hi Mike...

There is less spray and also a distinctively different pattern.

This is no doubt caused by the fences and the effect they have on the flow off the foil. You can really see it from the masthead camera. It's not only the amount of spray but also the orientation of it. We aren't hitting the back float with spray off the underside of the foil anymore for starters.

I'll sned some pictures through in the future to show you some of the great footage we are getting onboard that shows all this in amazing detail. The new GoPro's 2's give incredibly detailed images. That said... they do have some pretty big issues i.e. they freeze up all the time. We can take still images that show all sorts of fascintaing interactions between the wake, spray off the front float, rudder wakes, fence spray etc. well worth the effort.

Cheers, Paul.