Sailrocket

Last time I dare this place to show me a good blow... Cheeerist!

Mon, 21 Nov 11 20:50

Jeffro looked at me funny the minute I said "C'mon Walvis, I dare you to blow" earlier today. You really shouldn't messThe wind was filling in late and I was worried the forecast was going to struggle to materialise. We didn't head out until around 3p.m. The wind was filling nicely. It was 25 at the timing hut so we went straight to the top of the course. We had changed a few things and wanted to make sure things were right. It was just as well as the rig was raked too far forward and we had to mess with it for a bit to get it right.

The wind kept building and Helena was calling out 32 knot gusts by the time we started to get in shape for a run. The funny thing is that we are getting used to these winds now. I messed around too long in the cockpit as I was getting eased out onto the course by the RIB. I had dropped the quick release mechanism for the safety harness and pondered just doing the run without it. I looked around at what I was doing and decided that that was the typical decision you explain later from a wheelchair. I eventually found the piece and got harnessed up. It was pretty damned windy and rough. I was keen for a big run though and this is what I wanted. VESTAS Sailrocket 2 was released but once again struggled to bare away from the wind. Something about the wind and waves makes her weathercock in stronger winds. I tried a few tricks but she just sat there head to wind. I had to gently try to ease her forward on the edge of stalling the tiny rudder before she bit. The trouble was that I feared I had damaged the horizontal lifting, roll control flap as the leeward pod buried between waves. Sure enough as VSR2 accelerated the flap came free. It was hanging on by a small control line but eventually broke free.

NOW THAT'S NO WAY TO TREAT A LADY!

I pointed wildly to the support boat and they retrieved it whilst I began to line up the course. Damn it was rough and there was a hell of a lot of spray in the cockpit. I struggled to see the beach and just had to bare away when I felt it was right (ah, the good old days of VSR1). The forward flap was smacking into the waves and the leeward pod was sitting hard on the water without the lift that is normally generated by the departed flap.

The boat just felt draggy. I sheeted in hard but we just weren't accelerating as we should. I feared that the mods to the foil had created too much drag. I was still getting spray in the cockpit which is a very bad sign as it means we are way underperforming. Oh well, that's that box ticked then. I parked the boat without drama and waited for the boys to eventually come along after retrieving the undamaged flap.

I had no idea how fast I had just been as the bastard GT31 gps we use is about the most useless piece of equipment we have on the boat for providing simple speed data. I despair at the people who design that crap! Later we saw did just shy of 48 knots and about a 45.2 knot 500 meter average. Nothing flash and about what it felt like.

We really shouldn't be sailing in that stuff.

We lowered the rig and went back up to the timing hut. The run was a mess. I watched the video of the rooster tail and saw the change that the foil mods had created.

NICE PLOUGH EH?

I got Nick to wet and dry off the small ridges we had added to the back of the foil. We managed to remove the wing extension and took it into the igloo hut where we reinstalled the horizontal flap.

The wind was already hitting 36 knots.

Walvis had come to the party... and trashed it!

We stayed on nonetheless to see if it would abate. It was a very low tide but strangely enough the water was still blowing over the beach from the lagoon behind.

We waited and waited and eventually came home at sunset as the wind peaked at 37 knots.

I'll admit to feeling a little dejected. The whole day just felt messy and there was no magic involved. There was no breakthrough and no big numbers. The fact that it was also the only reasonable looking day on the forecast didn't help. Oh well, I guess we ticked a box. It was a rough trip the long way around the shallow bars that guard the lagoon. The whole yacht club was whistling in the wind. Still, we managed to put VESTAS sailrocket2 away in one piece. I gave her a pat on the snout. We'll work out what makes you tick yet girl.

So the forecast looks flat. It gets hard to trust when a day like today overperforms so much. I will watch tomorrow closely before we decide to head to Luderitz to watch the kiters and deliver an observer. I really would like to see them in action though.

Righto, so that's our first run out the way. We are still in development and that is part of it I guess. We are a little bit smarter after today and have a whole new job list as well.

I'll never dare you again Walvis. Like I say, I'm not superstitious... but in this game I can't afford to be wrong!

Here's a pic of Gordon and Ian from Scotland who came over to see the action. we distracted them from other tourist activities as we told them that seeing a boat like this in action is truly one of the rarest things you will ever see. They chucked a few notes our way for the post-record piss-up. Nice on guys, glad you came out!

Cheers, Paul

4 comments

First record run...COME ON WALVIS, We're waiting!

Mon, 21 Nov 11 10:19

It's Monday and it's forecast to blow today. This forecast should give us gusts to 30 knots and with this we should see some good speeds.

VESTAS Sailrocket 2 is really still a work in progress but now this progress has a sense of urgency as it is being done under the watchful eye of the WSSRC (Record governing body).

We are super keen to get on the water today. The weather has been very flat and looks to continue being flat for the forseeable future after today. Come on Walvis, we're more ready than we have ever been, give it to us!

More fairings are now present on VESTAS Sailrocket 2. The strut now has a feathering fairing fitted and the front float strut now has a trailing edge fairing fitted. Little details are constantly being improved and systems refined.

The kite-surfers down in Luderitz finished their record attempt a week or so ago which freed up the WSSRC record commissioner to come up and watch over our 28 day period. The other day I has Sebastien Cattelan contact me and ask me if he could have him back for this coming Tuesday and Wednesday as they have a good 'blow' on the way and desperately want to have one more shot at the title. I basically said that this would be fine by me providing that our attempt takes precedent and is not hampered in any way i.e. if our forecast means we are not sailing then by all means he can have him but if things change on short notice then he must come back regardless of the situation in Luderitz.

I thought that the big problem would come from the WSSRC not authorising this arrangement but this proved not to be the case. They stated that they didn't want any bureaucracy getting in the way of a proper attempt if possible. I totally applaud this stance. We could of played games with keeping the commissioner on site here to hold the competition back but I simply don't want to see that type of crap enter this game. It's hard enough to get to this stage for any project without having different projects trying to undermine each other. Still, you do have to consider all the implications and the risks it now introduces to your own project. You have to be aware that you may expose yourself unnecessarily to risk by having your 'man' stuck next to a rolled over car in outback Africa as you try to whizz him back and forth over 700km of semi-dirt roads. Any number of scenarios now come on the table. It's a tough decision but we will try and be as helpful as possible as the shoe could just as easily be on the other foot in the future.

I told Seb that I would wait until midday here to make the final call.

If our own forecast is flat on Wednesday then I will try and get down to luderitz myself to go and see this trench in action. I'm sure it's a spectacular sight/site.

The first 'fingers' of a SW wind have just wafted across the glassy lagoon here. The cool breeze has taken the sting off the morning sun. Come on Walvis... COME ON!

We have so many ideas and theories about what is happening with our boats performance and we still have so much to try. The matchstick camera has arrived and we have made a tiny streamlined fairing for it so that it can be attached to the main foil hopefully to film the ventilation and/or cavitation taking place. It will be absolutely amazing if this camera works. I give it a 50/50 chance. It won't be on for today but it will be for the future.

Righto, let's see what the day brings. COME ON WALVIS!

We will do a twitter feed from the beach today and it will come up on the front page of the website as well (you need to keep re-freshing). I believe all the links are on the front page for the live-feed.

Cheers, Paul.

3 comments

Hey-ho... let's go. World record attempt begins!

Fri, 18 Nov 11 10:24

Here we are, direct from the first day of our first world record attempt with VESTAS Sailrocket 2.

Mike Ellison from the WSSRC is now on-site to watch over our upcoming attempts.

We had to commit to this attempt around a month ago due to the rules of the WSSRC. We were hoping to be hitting world record speeds before booking a record attempt but we aren't quite there yet. We are close in some ways but still yet to convert. Nonetheless, I am entirely comfortable with commencing the record period now and believe that we have every chance of success.

On our last run we ventured out in over-the-top conditions and did it with ease. Of course we were hoping for higher top speeds but in hindsight what we demonstrated was the capability of the boat and team to operate in all conditions. from here on in the rest is down to refinement.

Whilst most casual viewers will just look at the final speeds, so much of the big problem is making a boat that can be handled safely in every other situation that will allow it to get into its ideal operating environment. Putting a wing up in waste deep water on a windsweapt beach with winds over 30 knots can very quickly go wrong if you are not in control. It is often the fear of this that stops you from doing it. We no longer fear this which means we can now pour on the free power of stronger winds if we have to. One problem here is that with stronger winds comes bigger chop. VESTAS Sailrocket 2 copped a real pounding on that last run. Every part of the boat got jerked, flexed and wrenched and yet she was stable and in control throughout. She's a tough boat as she is made for much higher speeds.

So, refinement eh? It would appear that what we did on that last run was simply throw a heap more power into the equation... but not go any faster. This would suggest that we have hit a wall. The speeds of around the low-50's would suggest that there is some sort of cavitation happening that is not ideal. I say 'ideal' as the new wedge foil is designed to utilise either cavitation or ventilation. I believe that there is a whole world to explore between the attached flow of water we are used to on conventional foils and the other extreme of fully 'super-cavitating' sections where a bubble of air in one form or another breaks off the low pressure side and extends way past the the back/Trailing-edge of the foil. From a hydrodynamic point of view it's pretty fascinating.

In a way we are trying to make the new foil lose 'grip' with the water on one side... but we don't think it is. We have now added a little ridge on the back of the foil to help trip the flow of water off it. In some ways it's like driving sideways in a car. In order to get into the best sideways cornering mode you need to trip the car to make it lose grip and slip sideways initially. You need to jerk it out of balance.

In our case we don't want to make the flow so messy that it destroys our low speed performance so much that we can't get going. We need to play with the size, shape and position of this little 1mm high ridge so that it trips the water at just the right time. Well, we are very well placed now to play with this. VESTAS Sailrocket 2 has put us squarely in the laboratory and all the ingredients are in place. The boat is right and the foil we have is a great starting point.

We must also keep our eyes open for what we may be missing. Sometimes there are silly,basic things that you look back at and can't believe you missed. This is where all the video and data collection becomes so vital. Every time you watch a video you see something different. It might be where the spray is hitting or the angle of the wake. There is just so much info there.

Anyway, here we are... and it feels good. I am always nervous about the little gremlins that can creep in and undo all your hardwork in an instant. We have extended the tail of the boat by 1 meter to increase the shroud base and make it more stable whilst rigging and launching. This process has enabled us to change all the rigging (thanks MARLOW), remove any unnecessary items and add dormant safety features throughout. We will continue to go over the boat every day.

The kitesurfers in Luderitz have finished their attempt. We have a complex boat, they have a complex course. The record we are chasing remains that set by Rob Douglas at 55.65 knots.

Are you getting the impression I want it? Good:)

Cheers, Paul.

15 comments

A big hard push before the record attempt starts...

Sat, 12 Nov 11 18:22

Well I'm happy to say that we are back all safe and sound after going sailing on perhaps our windiest day.

We did two runs today. I wanted to get back in the swing of sailing in punchier conditions. The first run was a little uneventful with a peak around 46 knots. The wind felt like it was going to build and was still a little west. This makes the course a bit more downwind which in turn doesn't allow us to build up as much apparent wind as we would like. I spent a large part of the run playing with the new flap control line on the wing extension. This is there to control the height of the leeward pod. It did seem to be one string too many in there and quite hard to get right as the boat is rarely in a steady state as it surges and sags whilst bi-secting the gusts. I have the mainsheet in my right hand which is also steering... and now the leeward flap control (let's call it the 'roll control') in my left hand. I really do very little steering although I need to pay attention to what is ahead of me as well as what the wing is doing. The workload is increasing in there so it might be getting time to fill that back seat in earnest. VESTAS SR2 felt as stable as ever although I never got the real solid surge that means big numbers. When I bore away at the end of the course, the speed dropped off quickly. This usually indicates that the wind is indeed too aft. Whilst we put the rig down we got some solid gusts. the day was definitely building. The peak speed was only 46 knots and that in itself wasn't very satisfying. It's hard to know what the wind was blowing as it can vary from 22 to 29 knots and swing through 20 degrees. Fortunately TACKTICK had sent us a new wind wand and we had that in place on the actual wing so I'm expecting some pretty handy data.

Seeing as the run went off with little drama, I felt confident to go up the course for another one as Helena called out gust peaks of 31 knots. It was time to go for a big run. It felt much better to be on the water in a sailing frame of mind rather than sitting around looking at a wind readout debating the pro's and cons. I knew this would be our last chance before the record attempt starts in 6 days so was happy to give it a nudge. We stopped in at the timing hut on the way past and I double checked the wind data. I didn't see any 30 knot gusts whilst there but I saw lots of 29. It was definitely getting windier. We headed to the top of the course and rolled straight into a run. Helena was calling out gusts to 32 knots. This was getting pretty wooly but the boat was behaving itself. We had found some rig setting where it seemed to like to sit before the sailing starts.

Once released from the support RIB and in a good position to start a run, I began going through the procedures. For some reason VSR2 stubbornly refused to bare away. I oversheeted to the max but she wouldn't turn. She was sliding sideways pretty rapidly and the leeward pod was dipping hard. The whole horizontal wing extension was being pushed onto the water as the stalled wing put a rolling moment onto the boat. There was alot of wind. I pushed hard in the design phase to keep that wing high out of the water for just such an occasion. The lower the wing is, the better it works in ground effect... but this was the reality of sailing in rough, top end weather. Every time the designers creapt the wing down, i would push it up again. We all want speed and efficiency but then I have to live with the real practicality of the whole thing. Overall this boat is just so much better than the first boat on this front. VSR1 would have simply sunk today.... just before hitting 53 knots in 5 seconds and about 200' high!

Finally a wave combo helped the nose turn away from the beach and we dropped into mode. The start up was quick and the acceleration came fast. There was one surge during the bare away onto the course which was remarkable. maybe it is when all the apparent wind lines up with the fuselage. I don't know... but I'll look into it. There was no doubt it was a fast run. It felt very solid and steady. The roll control seemed to work fine. the new mainsheet with the HARKEN micro blocks is an order of magnitude better. VSR2 felt fast with a couple of big spurts in the run I started a turn downwind to burn off speed. She burnt off some speed but was also sailing out into lumpier water still doing well over 40 knots with the wing eased. I was rapidly running out of options other than a big right turn into the wind. This is a big, bold and fast manoeuvre that you have to commit to. The pod literally flew as it went swinging round the outside. The boat seems to accelerate into the turn as it briefly hooks into the apparent wind again. As the fuselage is skewed twenty degrees to the direction of travel, you get the impression that you have turned past head to wind. The beach comes up quick and you have to keep turning hard until the boat just stops. then you have to quickly lock the rig off and trigger the main foil release to stabilise everything. All the while still draining the adrenalin from your system.

It felt like a big run. It felt faster than before. I noted that the yaw string was still well off being aligned with the fuselage indicating that we were well off being as efficient as we were supposed to be. That to me is not a good sign.

The numbers just in are as follows...

Max speed (doppler)- 52.13 knots

500 meter average- 49.22 knots

100 meter average- 51.6 knots

SMOKING, REAR COCKPIT HATCH IS ON.

52 KNOTS IS STILL QUICK... JUST NOT QUICK ENOUGH!

SHOWING A BIT OF RUDDER IN THIS ONE!

Whilst 52 plus knots would normally be a good speed, this was top end conditions and I expected more. I really wanted to be at least in the high 50's or even get a peak at 60 in these sorts of winds. Hmmm... it would seem that we may still be up against our old speed-sailing nemesis of speed sapping cavitation. We may be getting cavitation on the leading edge which is not joining up with the ventilation at the back of the foil i.e. we don't have a 'super-cavity'. We all think that we still have a lot of attached flow on the back of the foil. This is not so bad, we simply have to start playing around with ways to trip the flow off the back and try and induce this super cavity. In many ways todays sail was really good. We sailed relatively comfortably in honking winds, we got a clearer picture of where we are performance wise and we got a heap of data off the boat to help us get sorted. Sure, of course I want... I need to see the big numbers to be confident of beating the kiters... but they will only come with understanding. It seems that pure balls and luck won't be enough.

It's always a pleasure to put the boat away after a big day like this. I'm once again sending this from a rattling container. Tomorrow is going to be a bit mental wind-wise before a light forecast for the rest of the week.

Well, the original plan was to be breaking record speeds before the record attempt started. We aren't there yet. If we do hit those big speeds then it will be done for the first time before the eyes of the WSSRC official. I was really hoping to nail it today. To at least top Hydroptere's speed would have been a good start. Oh well, not to be. Like I said, we gave it a nudge. If we're not ready, we're not ready. We still have a few tricks up our sleeve. We'll get there.

Cheers, Paul

13 comments

Step away from the edge... too much wind today.

Thu, 10 Nov 11 21:33

We headed across to speed-spot today with a forecast wind of 24 knots. The day was shaping up nicely.

We had a few new additions on VESTAS Sailrocket 2 with the TRIMBLE GPS that will be used for the record timing getting its first ride and the rear cockpit cover being fitted. There are many more small refinements which are finding their way onto the boat as we continue to "sharpen the blade".

The wind was already strong by the time we got to the timing huts. It was hitting 30 in the gusts but still hadn't swung far enough to the south. So we waited. As it swung it built... we were seeing gusts of 34 knots. This was too much.

RISKS...

If we were getting towards the end of a record attempt then it would be worth risking sailing on these days. There is a strong possibility that this boat could deliver outlandish performance on such a day if we could get it onto the course. It has no stability limits like normal boats, it is structured for it and the foil should continue to perform better and better as the speed climbs. Oneday if we do have to play this card... it may well come off big time. On the flip side, this hand comes with a degree of risk. I don't think that it is the actual sailing that is the risky part. It's the rigging up and general handling of the boat as the rig goes up and down. We are constantly trying to improve this system. We haven't fumbled this stage yet but it still spooks us a little. Part of the problem is the relatively small shroud base of the boat. We are discussing extending the transom by a meter and a half just to give us more rig control. It actually isn't that big a job. Moving the forestay further along is easy. I'm starting to think that this could be the biggest go-fast option at our disposal. If we are totally confident to rig up in over the top conditions then we will push the boat as hard as we can. It will certainly assist in the decision making process for what is too much. Extending the shroud base was always a considered option and we do have the piece ready to splice onto the back of the fuselage... I'll sleep on this one.

So anyway... back to speed spot. We were all tooled up and had nothing better to do so we continued to wait and monitor the wind. Here's some pics.

YEAH... IT WAS PRETTY WINDY, EVEN FOR THE NEW BOAT!

THE FIVE HOUR STANDBY DEBATE ROLLS ON...

VESTAS SAILROCKET2 HANGS OFF THE BACK OF THE SUPPORT RIB WHICH IS ANCHORED. THERE IS ALWAYS SOMEONE IN THE RIB.

THE FLIGHT PATHS OF THE MAJESTIC PELICANS ARE ALWAYS FASCINATING TO WATCH

A LONE JACKAL WAITS FOR US TO LEAVE THE OLD TIMING HUT SO IT CAN SHELTER.

The fact is that we have another three days of solid wind forecast before the record period even starts. Right now we feel that we have it all to lose by getting too cocky. VSR2 is fast and the record is within our reach. We don't need to be lucky either, we just need to do all we can to stack the deck in our favour for when the WSSRC come. The whole debate rolled through my mind as we stood-by waiting for the winds to drop. It was good thinking time. I tried to focus on the forces that were shaping my decisions and consider how they could be individually changed to bring the decisions that bring the speed. It does all come back to the general boat handling in strong winds. We need more solid reliable hands (we are a man down at the mo') and a more reliable system. Wings can get damned spooky if you don't have full control over them at all times on windy days.

As the photo's show, this was a windy day. 34 knots is windy in anyone's books. The fact that the kitesurfers are looking for 50 knots is just mental. The tiniest puddles get choppy in 35 knots. It's no surprise that even their narrow trench has chop issues.

The fact is that we don't want to be sailing in anywhere near this much wind. We should be much more efficient than that... however, we are here simply to go as fast as we can and we will use whatever tool we have at our disposal. We have a very tough boat so why not use it? We can work on refinement later. Right now I just want that damned record. I feel close, like I'm in the room with it.

Back to speed-spot. So we waited but the 30 + gusts kept coming. At 6 pm we decided to can the day. Whilst towing VSR2 back to the Yacht Club we all noted how windy it really was. I don't know if it was the right decision not to sail but every time I bring the boat back from a windy day in one piece I know it wasn't the wrong one.

We now have one week until our record attempt starts. A good old hand is flying down to join us from here on in which will be comforting. You gotta love people who just drop everything to come and help when the call goes out. I'll sleep on the decision to extend the shroud base as there are always considerations that need considering such as re-rigging, structural loads and so on. Tomorrow promises similar winds to today so we will see how we go

Cheers, Paul

1 comments

Happy to be standing by... watching everyone else crash!

Mon, 7 Nov 11 18:17

Well we have just finished doing the full assembly of VESTAS Sailrocket 2 and she now sits quietly beside us under her soft cover. Nick has finished fairing the repaired main foil and it has been fitted to the boat and the beam repair has had her first coat of undercoat in preparation for tomorrow's top-coat.

We are pretty much ready for action.

I am very happy to be back in the hunt. Things could have been way different if the main foil had of failed the recent load test. It didn't so here we are. Probably in better shape than we were before the recent mishap.

A few improvements have already been added in the form of more HARKEN blocks in the mainsheet in order to reduce friction and the addition of a wing-extension flap control so that I can manually adjust the flying height of the leeward pod during a run. I have decided against an active system until I just try this. I figure I can pre-set the flap so that it will generate about 70-80% of the lift required to fly and then just tweak the last bit. The fact is that I don't need to play the mainsheet during a run... just let it go in an emergency and there is only very little steering to be done once comitted to a 500 meter course... so I might as well go fly a pod!

The weather is beautiful today. Blue skies with hardly a breath of wind. Some times it is nice when it is like this as you can get so much more done. Working outside in the cold, strong wind gets tiring. The tools get blown away, you get sand in everything and the resin stops curing with the cold. The funny thing is that we are so used to the wind turning on around lunch time that it completely unsettles my mental clock when it does this. It's 6 p.m. but it feels like lunchtime.

So here we are, back on full standby. Every time we bounce back I appreciate so much the sight of the fully rigged boat sitting beside the container ready for action. To me it's one of the most beautiful views of the project.

It is now only 10 days until the record attempt starts officially. The next week is shaping up with a very solid wind forecast. If it pans out then it will be a perfect lead into a record attempt as we should get the chance to push for the required speeds of 60 knots and above. We will only really know if we are truly in the ball game for the outright world record if we see these speeds. It is entirely possible that we still have to learn a few tricks to get up there in which case this will be just what we need.

The kitesurfers are patiently waiting for more breeze down in Luderitz. The clock is also ticking for them. They need one more big forecast if any magic is going to happen. We too watch their forecast with great interest. I'll be perfectly happy if they leave the damned hurdle alone for once.

During our repairs and quiet periods we have been watching the Volvo Ocean and the Transat Jacques Vabre race. It has been disappointing to see so many failures on so many boats. The boats are so highly strung and get pushed so hard that failures are inevitable yet I can't help but feel that there is something wrong with modern yachting. Too many are still falling apart. I'll leave it at that for now. I feel for all those teams who see their dreams dashed by that horrible cracking sound. It's a truly shit feeling but with every dawn comes the resolve to push on and make things right.

Righto, beer-o-clock.

Well done Nick and Alex.

Cheers, Paul

3 comments

Pheee-ew!!! 60 knots here we come!

Thu, 3 Nov 11 13:08

Well we just did the full 60 knot-plus load test on the high speed foil and I am very, very, VERY happy to say that it passed without the slightest peep. We even took it a bit over the recommendation just to be sure. I was nervous as hell as the implications of a failed foil are pretty big.

The gig is now back on to carry on with the pursuit of speeds over 60 knots.

We were looking for a test bench to test the foil but the local ones were all busy. We rigged one up between the containers outside and just got on with it. The deflection between the tips was measured throughout. The very tip deflected about 5 cm at a load equating to over 65 knots.

Yesterday we decided not to drill and bolt the foil in the repaired area as the holes simply would have been too much of a focal point for cracking. That means that the load the foil could take would be all down to the quality of the repair.

If the foil had failed then it would probably mean that we would be back to pushing the limits of conventional foils. For all we know the conventional foils may be capable of getting over the current record of 55.65 knots... but then again, maybe not (without a certain level of work anyway). We know that the new foil will be a safe and reliable way to attack the high speeds we are chasing. I think we are close to achieving a life long dream here. If that foil had of failed... well we would probably be set back a year as I doubt we could have turned the situation around and had a new one this year.

We had already started trying to source High modulus carbon and potential builders back in the UK where the moulds are. I'm so glad we don't have to go down that path now. I gave us a 50-50 chance. It's so hard to know what is going on inside one of those repairs as you can't see inside and you can't be very exact about the quality of what you are putting in there.

We decided to do a load test for a speed just over 60 knots with a moderate safety margin. That speed should enable us to get the job done. There was no pint doing the full load test and breaking the foil. The old adage of "Don't shoot for the stars when the moon will do" applies. If we do get these speeds in our TRIMBLE gps 'bag' then we can do another load test to a higher number.

I'm so relieved that the foil passed. I was waiting for that sickening carbon fibre 'crack'. I've heard that too many times. It's the sound I have come to despise most. It's never a good sound. It's the sound of disappointment, of lost time, money and quite often dreams. Well, our dreams are still intact.

Nick has been doing a great job on the beam repairs and tomorrow we will start the full reassembly of VESTAS Sailrocket 2. There is very little wind forecast for the upcoming days so we can do a very thorough preparation of the boat. The world record attempt is only two weeks away. We are back in a good place.

The kitesurfers down in Luderitz haven't been showing any real magic as yet. Apparently they have found that there is a lot of chop in the channel caused by the deep TWA (true wind angle around 140 degrees to the wind) i.e. the chop is rolling down the length of it. Too much chop in a 3m wide channel! Things are never as easy as they first seem. I'm sure they will work out some solutions. Whilst our boat is complex, so is their course and operating environment. I would love to go and watch them in action but the fact is that we need to use every good day that comes our way now. Hopefully they don't raise the bar any higher. I don't want to have to go through the stress of another full load test just yet!

Cheers, Paul.

4 comments

The windy workshop...

Mon, 31 Oct 11 15:01

OK, it’s all coming back together. The wind has been howling here throughout our repairs. Yesterday was a real container rattler. Slowly Namibia infuses her way into the structure as the sand inevitably finds its way into various small laminates.

The kiters will be going for it further south in Luderitz today (more on that later)

The beam repair is coming along nicely. We had made up all these moulds to bring down with us but the container ended up so crammed full of boat, wings, RIB’s etc that we had to leave some things out. This means we had to make new moulds down here and that all takes extra time. Never mind, we have them now. Alex and Nick set to on the job and I lent my input after having done numerous beam repairs in the past.

YOU CAN SEE THE CRACK ALONG THE ORANGE LEADING EDGE. THE SECOND PICTURE SHOWS THE SHEAR WEB INSIDE THE BEAM. YOU CAN JUST MAKE OUT THE BUCKLE IN THE SKINS JUST TO THE LEFT OF CENTER. THERE IS ACTUALLY A LOT OF DELAMINATION ALL AROUND THIS AREA CAUSED BY THE BUCKLE. WE HAD TO REMOVE ABOUT 1.3 METERS ALL IN ALL.

Right now the beam is going together right beside me and it will be pretty much rejoined by the time this is posted. We could be ready for sailing tomorrow but seeing as no wind is forecast I have told them to spend the extra time to get it all spot on as there is no rush weather wise.

We have been over to ‘Speed-spot’ and recovered the main parts of the wing. Many bits are still over there in the ‘igloo’ shed so as to save some space back here. The wing really did come away unscathed. I have pulled the key components apart including the strut ‘Collar’ and the HARKEN car that all the breaking loads went through and they are perfect. I think that the breakage may have been initiated by a load we put on the beam early on in the sailing trials at the start of the year. We had a clearance issue between two wing sections that prevented the wing from ‘feathering’ and it put a huge load on the strut. It survived then... but failed this time under what seemed like a lot less load. Maybe cracks were initiated then that an external inspection couldn’t detect. Well, it’s definitely stronger now.

The beam is not a big issue. The cracks in the main foil are a much bigger issue. If we can’t use this new, high speed, ventilated foil then we can kiss 60 knots goodbye until we get a new one. Those little hairline cracks indicated that something was going on inside the laminate which needed to be understood. We put load on the foil at the tip... up to 360 kg and it didn’t fail.

It did deflect more than it should have and the thickness of the foil changed by 1 mm. Something was opening up inside. The only option was to cut it open in the least destructive manner and have a look.

The biggest weak area of foils of this nature is the bursting loads in the curved elbow... especially as they are loaded to open up the curve rather than fold it as on more traditional curved foil (on say an ORMA trimaran or some modern beach cats). Once I ground away the carbon tapes that hold the two foil halves together along the trailing edge of the curve, small cracks could be seen. With a tiny amount of load these cracks just opened up and spread as in glass. Not a nice noise in composites.

I ground away and chased the cracks through the thick ‘Spa-bond’ glue that was used to join the two foil halves. About 50 mm in I got to the first carbon fibre ‘shear –web’. These are used to put carbon fibres across the join line rather than just to rely on the strength of the glue. The carbon is much stronger and better at transferring the immense loads for one side to the other. It seemed the crack had also extended to this web and once again, under a little bit of load it had opened up. It was now time to chase the whole crack to its full extent. I dug out a big groove all the way around the transition foil (the curve) all the way to the shear web. I laid the foil nose down and filled the whole groove with some ultra slow epoxy resin and then pulled on both ends of the foil with a 6:1 purchase to load and unload it. This forced the crack to open and close.

I had big G-clamps at either end of the crack to stop it running further than it had to. When the foil was loaded up it ‘drank’ the resin and then spat it out as it was unloaded. I did this repeatedly until all the air had come out and no more resin was going in. Then I left it to cure. Next we jammed in rolls of fibres at +/- 45 degrees and 0/90 degrees to take the shear and bursting loads. These were vacuumed in in two stages to try and get as much air out as possible. The whole grove has now been filled in this manner rather than just having glue in there. Today I will vacuum on the carbon ‘tapes’ around the outside to seal it all up.

It is impossible now to tell exactly how well this has all bonded on the inside. I think it’s about as good a job as we could do without getting too destructive. We are also discussing the option of bolting through the foil around this bend. Of course this option has its good and bad sides. I have seen this option used in such places as Groupama 3’s beams where similar loads are exerted on the curved sections where the beams go down into the floats. We are still looking into this option as it has to offer a clear advantage as drilling holes in a highly loaded area is not something to be done lightly.

So once we have joined it all together and cured it under high temperature... we have to go and do a full load test. For me this will mean taking it up to a load equivalent to 65 knots with a safety margin. We will do this here in Walvis Bay. We also did it before in the UK and it passed. We did hear cracking during this procedure but it still took and held the 1 ton load at its centre of pressure. The foil was not faired and painted then and I wonder if the cracks we were seeing were not just because the fairing/paint had not been subject to this load until our last high speed run. It’s entirely possible that the foil had developed cracks during the initial load test but still managed to take the load without failing. The best way to see this is to measure the deflection during the load test. The cracks may also have propagated whilst being worked. We noted a much larger than expected deflection during the last 360 kg load test which is why we chose to operate on the foil.

Hey... we just joined the beam back together with the new section. A tricky job that took a lot of jigs, clamps, lasers, spirit levels... and spabond. It looks good.

THE CONTAINER FLOOR IS THE FLATTEST SURFACE WE HAVE. RIGHT NEXT TO WHERE MY ERM... OFFICE IS. THIS IS WHERE THE MAGIC HAPPENS;)

KITERS GOING FOR IT...

It’s getting pretty windy here now. Hitting 30 knots. It’s hitting over 40 knots down in Luderitz and the kiters are tearing it up in the new channel. Apparently Seb Cattelan is already at 48 knots. Today should be a big day for them and a great trial for the new channel. I reckon it’s pretty damned dangerous to be doing what they are doing down a ditch with dry land either side... but then there are lots of things we humans do which is far more dangerous i.e. I never really understood how dangerous it is to race bicycles down tarmac alpine roads until I did it this summer. It’s bloody dodgy and people get seriously messed up. Still, it’s your choice whether you do it or not and I’m all for freedom of choice. Still, I recommend a helmet at least.

As I have said before, I fully expect the kite surfers to go a fair bit faster than they already have. There are many things that can give them gains. I’m not sure how much they rely on their small fins for speed as these would be the only areas limited by either ventilation or cavitation. The rest of the aero/hydro package is only limited by efficiency. For VESTAS Sailrocket 2 to beat them we have to iron out all the bugs relating to strength and overall balance and then we too can just focus on efficiency. If this foil passes on the upcoming test bench... then we will give it as hard a push as is necessary in the upcoming record attempt. I will be wearing a nice thick, expensive helmet.

Just heard it’s gusting 50 now in Luderitz and the new channel is working fine. Sebastian Cattelan has hit just over 50 knots already despite having a crash on an earlier run. The container is starting to rattle again. It's all happening in Namibia. WOO!

Cheers, Paul

4 comments

Zero...

Tue, 25 Oct 11 18:33

Zero. Normally the number that precedes all others... but in this game it still seems to come immediately after 'hero'!

We just managed to drag our bird back in with a broken wing... well 'beam' anyway (wings fine).

We went out to speed-spot in 20-25 knots of wind with the more traditional sub-cavitating foil on. We wanted to see how hard we could push it. A few of the general boat settings need to be modified as this foil changes the overall balance as compared to the new ventilating foil.

We managed to launch VESTAS Sailrocket 2 just fine but up ahead of me there was a flock of cormorants working a school of something or other. VSR2 began to accelerate but I had to slow down to let the cormorants get out the way. I once sailed through a flock on a windsurfer expecting them to get out the way. It got messy as they are waterlogged and take a while to get going. VSR2 at pace would have been like some sort of GD harvester.

So I waited until I cleared them before accelerating. This didn't leave much room to the beach. VSR2 accelerated but I had to bear away quickly. She didn't quite have the speed to carry the apparent wind around with her and stalled.

We had used up a lot of the course and I was reluctant to do another run that would have me down in the shallows at the end of the course. I stopped just past the timing hut and called the RIB alongside.

I raised the foil and we tried to see if we could slowly slide VSR2 sideways back up the course as we had done before. By changing a control line I had restricted the ability of the wing to fully feather so we stopped the idea and made for the shore. It was here that the RIB yanked the nose the wrong way and the wing loaded from the wrong side. It gave a forward pitching moment which puts huge compression on the strut. The beam folded between the strut and the leeward pod and the wing pitched nose down into the water.

Shit, shit, shit. I've been here before only not with this boat.

Now to sort out the order of things before any other damage takes place. Quite often, especially with wings, you can do more damage after the accident than by the original mishandling. I jumped out of the cockpit and grabbed the forestay to stop the wing from flying up. Alex slowly motored into the shore. I swore a bit... but not that much. Sort of one long, loud one rather than an extended volley.

Once we got into the shallows we began picking it all apart. I was happy to see that the damage was quite localised and that virtually no other pieces had been damaged. The wing was miraculously undamaged. The strut, the HARKEN track and car, the leeward pod brackets were also all without damage. It was only a section of beam which, in the big picture, is relatively easy to repair.

So the new wing will spend its first night in the shed over on speed-spot. Hopefully its last. We managed to get the rest of the platform back safely and have already begun on the repair.

Overall I feel kind of lucky. It could have been much worse. These things happen. It was a handling mistake that we shouldn't, in hindsight, have exposed ourselves to. I didn't think it would play out like that... rather I thought that the boat would have slipped sideways. Well it didn't and here we are. You simply don't get it right all the time. Personally I'm pretty happy to have made it this far with such a radical boat. The carnage we had with the first boat taught me to incorporate some flexibility into the joints for just such a situation and these prevented a lot more damage today.

I reckon it will take us a week or less to be back in action.

So that's it. I can't say I'm happy about it... but I'm not going to overdramatise it either. These incidents are part of the scenery and we always get over it and comeback smarter and faster.

We just mounted a wing-top camera too... Caught it all beautifully... but I'll leave you with the fast run for now.

Cheers, Paul

4 comments

Riding the Rocket. Passenger perspective at 100kmh.

Tue, 25 Oct 11 08:58

Hi people here is the video from our 100kmh ride the other day on VESTAS Sailrocket 2.

Adam thought he was just in for a nice, easy jolly down the course... which is why he takes so long to absorb the number on the GPS at the end.

Sailrocket 2 Onboard at 100kmh on YouTube

Right now we are getting ready to go sailing today. We have substituted in the 'old school' subcavitating foil to see what we can max it out at. I suspect it will need some fences to stop ventilation but we will start with the basic shape.

We discovered some small cracks in the high speed ventilating foil and want to make some mods and carry out some further load testing before we attempt to take it to 60 knots. If we break it, we don't have another one. We are pretty sure it is OK but want to be totally sure.

Enjoy the video... we enjoyed making it!

Cheers, Paul

4 comments