Greenbird

First tests on dirt in light winds

2008-11-20T16:25:39Z

Here’s a couple of photos of our first test run on dirt in light winds (13-20 mph) at Ivanpah the other day. Fingers crossed for a bit more of a breeze during the predicted shift in weather system next week.

Greenbird on dirt at Ivanpah

2008-11-19T11:46:44Z

Now fully set up at Ivanpah. Another day in the hot sun, ironing out any last glitches and fitting a few new systems. No wind forecast today, and until 2pm that was the case, absolutely nothing.

Then, from nowhere, the wind set in blowing 18-25 mph, almost instantly, and I was not ready!

These are not record wind speeds, but very good testing winds. I worked frantically to finish the hydraulics and bleed the system and finally got the wheel covers on at about 3pm.

Pushed it out on to the playa and sure enough, the wind meter was now reading 13 mph, where it stayed till sunset (our self starting threshold is 18 mph of true wind).

Typical. However this is the nature of the desert, sometimes a good forecast does not materialise, and other times a nothing forecast suddenly becomes good for an hour.

There is a better forecast for tomorrow, so hopefully, we will get some runs in.

Arrival at Ivanpah playa

2008-11-19T10:22:01Z

Arrived today at Ivanpah after the weekend gathering supplies and tools. I did not expect to be back here now, when I left the ice craft up in Montana, so I left a lot of crucial spares and tools with the ice yacht and have had to duplicate a lot of that stuff now unfortunately.

However, I should get my lake permit this morning so setting up this afternoon on the lake. A lovely sunny day and some wind forecast for Friday Saturday so a good opportunity for an initial test.

I have got a 3g card for my computer, so I have fast internet direct from the lake, which will prove invaluable no doubt.

Setting up by myself, so might take a little longer than normal, but hopefully send pics this afternoon.

Greenbird - meet Vegas

2008-11-19T11:06:18Z

Picked GB up from warehouse in LA this morning. Now stationed at the test location near Vegas.

Can’t get the lake permit till Monday, so setting up next week. Will be on location till 1st December

Going Stateside for landcraft testing

2008-11-06T10:23:58Z

Landed in San Fransico Nov 4, on my way to Nevada for an essential test period. I will be using the November weather window to evaluate the performance on dirt before the best weather next March/April. However, it is not out of the question that we may get perfect weather during November! If this happens and we do get a record speed, then we are preparing to be able to move quickly and capitalise upon it.

It seems that over the last 8 years, the weather is getting more and more unpredictable and therefore we can’t afford to waste any opportunities if they arise.

I have spent many days over the past few weeks analysing weather records for about 12 possible locations in the US. What is very apparent is the weather event that the ‘Iron Duck’ had in 1999 (current record holder) really was pretty unusual, in the strength, steadiness and duration of the wind event. There has probably only been one or two occasions in the last 12 years when this has happened. This is not to say that strong wind events don’t occur, just they are of shorter duration and more random.

Therefore, I intend to spend as long as it takes on standby to wait for that opportunity. We can’t sail past the end of November, but once the playa’s dry in mid March, there is pretty much a constant window through to July (at a variety of venues). It may well be the case that I have to spend 4 or 5 months sitting in deserts or frozen lakes, but this is what it is going to take.

50 Knot ‘Barrier’ Broken

2008-11-04T15:57:06Z

On Saturday 4th of October the world speed sailing record (on water) was increased to 50.56 knots (93.6 Km/h) by kite surfer Alexandre Caizergues (FRA) at Luderitz in Namibia. This phenomenal achievement eclipsed the previous official record of Robert Douglas (also a kitesurfer) at 49.84 knots. Before Robert, the record was held by windsurfer Antoine ALBEAU (FRA) at 49.09 knots.

So why is this phenomenal? Well, it is phenomenal because it is an incredible feat of skill, strength and endurance. The record was set in winds averaging around 40 knots obviously with higher gusts. To stand up in this is difficult, but to control a kite and board over 500m (the record distance) is amazing. Furthermore, to record an average of 50, you need peak speeds well above this, and according to Alex’s GPS, he hit 58 knots peak speed with a 54.5 knot average over 200m. This is skill indeed and we at Greenbird salute you all.

So what’s with the 50 knot barrier? For years speed sailing records were set in boats, then later sailboards. Both these require a foil in the water to generate the side forces necessary to counteract the force from the sail. As the boats and boards got faster and faster, the rate of increase per record decreased and it seemed like we were approaching a theoretical limit due to the amount of force a water foil can hold before it cavitates (or more likely ventilates). To avoid a very lengthy technical discussion on the theory of cavitation and ventilation, it quite simply means, that at some point (at very high loading) the flow detaches from the low pressure side of the foil and almost all lift is lost, while extra drag is created. This transition normally results in catastrophic wipe-out, so lots of work was put into trying to delay this transition. We all also knew there are such thing as super cavitating (or fully ventilated) foils that work efficiently at high speeds way beyond the transition speed for conventional foils, but these are very poor at low speeds so switching from one type of foil to the other was always going to be tricky. It became pretty clear that this transition speed from attached to ventilated flow was around 50 knots and hence this was initially proposed as a physical barrier for speed sailors. Strangely enough, it turned out that ventilation was successfully delayed on windsurfer fins and the fastest boat, Macquarie Innovation and the limiting factor became drag. Had they been able to reduce the drag further and increase power, it would have come back to ye olde foil ventilation.

So why have Kite surfers eclipsed it so seemingly effortlessly? Well, a couple of reasons. Firstly, the kites are higher in the air than a windsurf sail meaning they are effectively sailing in higher wind speeds than their windsurf counterparts. Secondly, the boards already work exactly like a super cavitating (or fully ventilated) foil which uses mass (or momentum) transfer to achieve a reaction and hence side force. Using this principle, there is no hydrodynamic limit other than drag (air and water) factors to limit top speed. Therefore, I predict a new barrier will soon be established, determined by the sum of the aerodynamic drag from the kite, line and person, plus the hydrodynamic drag from the board.

I am not going to propose what that new speed limit might be, but there will be a limit ,and once the technical evolution is fully evolved (as it pretty much is in windsurfers) the top speed will be directly proportional to the wind speed. So, we may see different record categories for different wind speeds, which would give more credit to technical efficiency rather than just skill, body weight and brute force.

So will that be the final barrier? No far from it. The problem with kite surfers is that the maximum kite force will always be limited by the weight or strength of the person. To get real ‘pull’ you need proper ‘grip’ in the water and this can only be done with some kind of submerged foil. Once you get this to work, you can have a more powerful, efficient, high aspect wing in the air. Then there is a whole new ceiling. Maybe we wil be talking about the 100 knot barrier in a few years?

So how is it done, exactly? Don’t think I am going to tell you in a single blog, but one thing for sure, once the land and ice records are done, I am very much back on the case!

Here are a few links of interest, showing some of the different principles currently being tried by teams around the world:

Sailrocket - http://www.sailrocket.com
Macquarie - http://www.macquarie.com.au/speedsailing.htm
MoS - http://www.mastersofspeed.com
Luderitz - http://www.luderitz-speed.com

Rain stops play…

2008-10-17T10:46:54Z

After dinner around the campfire end of last week, with a group of landsailors from Perth, I went to bed around midnight, with the sound of rain still falling on the tin roof of the old mining exploration caravan we are staying in. In the morning the rain had stopped, but we found the camp area had turned into a bit of a quagmire, which indicated a lot of rain had fallen over the last 12 hours. We skidded down the muddy hill to the foil trays we had left on the lake surface to measure the amount of rain, only to find one of them had floated away, which gives you some idea of what we were looking at. The other tray indicated that between 15-20mm had fallen in the night, and the sky was still not clear. Later that morning more thunder clouds dropped another 5-10mm.

This had flooded the entire surface of the lake and has rendered it unusable for possibly another month, which sadly means an end to this year’s land record challenge, which is a very disappointing blow to us all. The Greenbird was in fantastic shape to shatter the record and it is very frustrating not to get any high speeds in whatsoever.

So why the peculiar weather and why could we not predict this? I will be going into a more detailed weather analysis in the next blog post, but in brief, July saw twice its monthly average fall in 2 days at the end of the month, then August saw its monthly average quota fall over the last 12 hours. If the rain comes in smaller showers with regular intervals, it can evaporate quicker and soaks into the soils surrounding the lake. When so much falls in such a short time, the clay in the soil seals the surface and streams start running onto the lake. This effectively increases the catchment area of the lake and means more water ends up pooling on the surface. It is not uncommon to have monsoon type conditions later in the year, but they are certainly a few months early this year, and almost impossible to predict.

So where from here? Well, the Greenbird is now dismantled and out of the big puddle and looking for its next record opportunity, the same time, same place, next year. In the meantime, we will have the Greenbird ice craft in action in Montana in January and February.

So how do I feel? After many years of uncooperative weather I am use to it by now, but it does not make it any the less frustrating. Almost every other sport or race has direct competitors, where it does not matter what the conditions are, they are the same for everybody and all you have to do is beat your rivals and there is always a winner.
In our situation, we have to wait to get the same (or near) conditions as the current record holders had in 1999 before we even have an opportunity to compete and this makes it incredibly difficult. When we can’t set a new record due to the weather, it is not like losing a race, but it is more like an athlete not even being allowed to enter the arena, let alone get on the starting blocks.

All we can do is maximise our chances of getting favourable winds by longer standby periods and looking at all possible venues. Persistence will always win.

Here’s our final video for this season from Lake Lefroy.

Record attempt thwarted by climate change

2008-10-17T10:57:22Z

This year’s land speed record attempt with the Greenbird is officially a washout. I held off travelling at the start of the short weather window because the lake was actually wet not dry and I’ve been waiting, bag packed, ever since for the call - but it didn’t come, or not the one I hoped for. Richard mailed me yesterday with the news - there’s been even more rain and still no wind. There’s no chance the lake can dry in time now, so we have to pack up and try again next year. There is a possible venue in the US we’re looking into for March though…

We’re pretty disappointed not to have even been able to get the Greenbird out of the starting blocks. And it’s an irony not lost on us while that while Greenbird is intended to show how the world might be getting around when fossil fuels run out - the changes that fossil fuels are causing to our climate right now appears to be the very thing that has stopped us.

In the next twenty years, I firmly believe that wind power will be our main energy source and wind-powered cars will no longer be the stuff of dreams. We’re dedicated to making this a reality, and at the end of this year hope to have our second generation wind powered car on the road here in the UK, an everyday kind of wind powered car. We need to change the world, nothing less will do and for that (amongst other things) we need a transport solution for world post oil. Wind power has the potential to provide this.”

I’ll be blogging about the wind-powered car at www.zerocarbonista.com so join me there.

Unveiling the fab new helmets – video

2008-10-17T11:03:03Z

We’ve just uploaded a fantastic video of the new Greenbird helmets which you can see in our Video Gallery. The helmets were designed and created for us (for free!) by Jason Fowler of JLF Designs. So a massive thank you to Jason and his team, who are the leading helmet paintwork specialists in Britain. They do helmets for some of the biggest names in Formula 1(like Lewis Hamilton!), as well as for GP2, DTM, MotoGP and Karting drivers. The design is just perfect - capturing the spirit and vision of what we are trying to do here with this project. Very proud to be wearing a JLF helmet…

And this great HD video was filmed & produced by our long-term partner BHP Sport - and they are currently here with me in Oz, doing another piece which will be available on this site soon!

Here’s a shot of the new helmet, but make sure you check out the whole video - in all its HD glory!

Good news, bad news…

2008-10-17T11:04:17Z

Well, the good news is that our film crew, BHP Sport are here and filming in earnest with the very latest Sony HD equipment. Early footage looks stunning and they will be posting Video blogs here shortly. Simon and the crew from BHP are great friends of the project and have been filming progress since the early days in 2001.

The bad news, is that it is raining, hard! Not sure how much has fallen so far but we will get accurate measurements from our rain collectors in the morning. We will then have to reassess the situation
and how this has affected the drying time, sailable area, etc.

Today was another tuning and tweaking day, with stall tests on the main wing and tail flap angle adjustment for starting. Wool tufts are stuck to the wing to visualise flow and show when stall occurs. Even though real operating speeds are much faster than these static tests at low wind speeds, the results should be fairly linear.

Simon and Andy from BHP battling the rain...

Temporary wool tufts to visualise flow...

Rain radar - not looking good!