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	<title>Greenbird &#187; Ice craft</title>
	<atom:link href="http://blog.greenbird.co.uk/tag/ice-craft/feed/" rel="self" type="application/rss+xml" />
	<link>http://blog.greenbird.co.uk</link>
	<description>The Ecotricity Greenbird in world wind-powered speed record challenge</description>
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		<title>Not nice ice</title>
		<link>http://blog.greenbird.co.uk/2010/01/29/not-nice-ice/</link>
		<comments>http://blog.greenbird.co.uk/2010/01/29/not-nice-ice/#comments</comments>
		<pubDate>Fri, 29 Jan 2010 15:14:37 +0000</pubDate>
		<dc:creator>Richard</dc:creator>
				<category><![CDATA[Ice Record]]></category>
		<category><![CDATA[ice]]></category>
		<category><![CDATA[Ice craft]]></category>
		<category><![CDATA[NALSA]]></category>

		<guid isPermaLink="false">http://blog.greenbird.co.uk/?p=442</guid>
		<description><![CDATA[Unfortunately, there&#8217;s been no improvement on the ice front. Dennis Bassano, the NALSA president and a friend from Santa Cruz, drove to the lake last weekend to see how it was and test his Class 3 ice yacht with some new skates. He reported back today and conditions are far from ideal. &#8220;There are clear [...]]]></description>
			<content:encoded><![CDATA[<p>Unfortunately, there&#8217;s been no improvement on the ice front. Dennis Bassano, the NALSA president and a friend from Santa Cruz, drove to the lake last weekend to see how it was and test his Class 3 ice yacht with some new skates. He reported back today and conditions are far from ideal. &#8220;There are clear patches between the drifts which are sailable for the small boats, but pretty brutal when you hit them. Definitely not speed record conditions&#8221;, he said.</p>
<p>As far as I know, there is no better ice elsewhere in the US right now, so no point in travelling at the moment either. So we have no choice but to sit tight at the base in San Francisco and continue to wait for things to improve.</p>
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		<slash:comments>1</slash:comments>
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		<item>
		<title>Thinking about Ice</title>
		<link>http://blog.greenbird.co.uk/2009/12/18/thinking-about-ice/</link>
		<comments>http://blog.greenbird.co.uk/2009/12/18/thinking-about-ice/#comments</comments>
		<pubDate>Fri, 18 Dec 2009 09:24:13 +0000</pubDate>
		<dc:creator>Richard</dc:creator>
				<category><![CDATA[Ice Record]]></category>
		<category><![CDATA[Ice craft]]></category>

		<guid isPermaLink="false">http://blog.greenbird.co.uk/?p=417</guid>
		<description><![CDATA[Well, it is getting chilly here in San Francisco so it must be getting towards that time of year, the Ice!
I have been working out here during the summer on a radical sailing project, not speed record stuff, but great fun with huge potential&#8230;. more on that later. My thoughts are now on the ice [...]]]></description>
			<content:encoded><![CDATA[<p><img src="http://blog.greenbird.co.uk/wp-content/uploads/2009/12/frozen-rain.jpg" alt="" title="http://www.flickr.com/photos/audreyjm529/" width="300" height="256" class="alignright size-medium wp-image-421" align="right" />Well, it is getting chilly here in San Francisco so it must be getting towards that time of year, the Ice!</p>
<p>I have been working out here during the summer on a radical sailing project, not speed record stuff, but great fun with huge potential&#8230;. more on that later. My thoughts are now on the ice record and getting the Greenbird ice yacht up together to take on this season&#8217;s ice.</p>
<p>Last year the rough ice (@ 70 mph) took its toll and there are a few bearings, etc that need replacing. I am therefore going to fly to the craft (sitting in its box near the lake) and drive it back from Montana (18 hr drive) this weekend and work on it for a while in our nice hanger in San Francisco. There are a few modifications I would like to do, so when the ice forms in Mid December, I will be ready and only a couple of days drive away from being set up.</p>
<p>So what modifications? Well, there are a number of things I would like to do including a nose job, a modified rig and parachute deployment system.    <span id="more-417"></span></p>
<p>1) New Nose &#8211; this is really a nose extension to try and absorb some of the bumps. Even though the craft geometry has been proven to work well on a smooth surface like tarmac, without the soft tyres, the hard ice transmits severe vibration through the craft (despite the rubber shock absorbers we currently have). Therefore, adding a long flexible &#8217;springboard&#8217; as it is know in ice sailing, helps absorb the bumps and aid steering.</p>
<p>2) Modified rig &#8211; This yacht was designed a bit like a drag racer, to accelerate hard in a short distance, on the runway in the UK. This means it has a large sail area and is not necessarily optimised for top speed. Now adapted for ice, it could manage with a fraction of its sail area, so I may make a new mast and remove the lower sail section.<br />
I will explain the pros and cons of this at a later date.</p>
<p>3) Parachute deployment &#8211; It may sound silly, but stopping is one of my big worries. The craft is heavy with very little friction (air drag), and unlike the land version, I can&#8217;t reverse the sail, so stopping may actually be very tricky. To help this I made a parachute, which made a big difference in last years tests, but I never made a bullet proof deployment system. As the lake has rather hard edges, it is essential that this parachute system works reliably, so a spring loaded ejection system will be incorporated.</p>
<p>So what are the chances of going really FAST? (as in faster than the land record of 126.2 mph) The unsatisfactory answer is that I am really not sure. Despite a huge theoretical drag reduction (loosing wheels for skates) it turns out that conventional ice yachts are actually slower than their land yacht counterparts. The reason for this is unclear and I am determined to find out. The reality is that it may take me a few years of testing, and probably a new craft or more to get to the answer. Either way, when I have finished it will be as close to the fastest wind powered speed on ice as possible, and I will know the answer to my question of what is the fastest wind powered vehicle on the planet.</p>
<p>It should be a very interesting journey and we have never been so prepared to take on the challenge. I will be revealing all my discoveries here and would welcome any thoughts or suggestions that may be of assistance.</p>
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		<slash:comments>3</slash:comments>
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		<item>
		<title>Back to dry land</title>
		<link>http://blog.greenbird.co.uk/2009/03/20/back-to-dry-land/</link>
		<comments>http://blog.greenbird.co.uk/2009/03/20/back-to-dry-land/#comments</comments>
		<pubDate>Fri, 20 Mar 2009 15:12:30 +0000</pubDate>
		<dc:creator>Richard</dc:creator>
				<category><![CDATA[Land Record]]></category>
		<category><![CDATA[America's Cup]]></category>
		<category><![CDATA[Ice craft]]></category>
		<category><![CDATA[Ivanpah]]></category>

		<guid isPermaLink="false">http://blog.greenbird.co.uk/?p=339</guid>
		<description><![CDATA[Sorry for the radio silence! But we’ve been using the time to move our focus from the ice and back onto the land record.
This is because the ice surface never recovered at Canyon Ferry and on March 1st it started to break up in the warming weather. 
So it appears that the only possible window [...]]]></description>
			<content:encoded><![CDATA[<p>Sorry for the radio silence! But we’ve been using the time to move our focus from the ice and back onto the land record.</p>
<p>This is because the ice surface never recovered at Canyon Ferry and on March 1st it started to break up in the warming weather. </p>
<p>So it appears that the only possible window for an ice speed record is during the time between when it freezes and when it snows. I sort of knew this before this year&#8217;s efforts, but hope springs eternal, right?</p>
<p>Anyway, the ice yacht is packed up in its trailer near the lake awaiting next year&#8217;s first freeze. I will be back there in early December, waiting for that first ice.</p>
<p>Thoughts now turn to the land version of Greenbird, waiting for me in storage near San Francisco. The America’s cup landsailing Regatta starts at Ivanpah (near Las Vegas) this weekend &#8211; and I plan to be there. </p>
<p>It is the biggest land sailing event of the year, encompassing the Pacrim (Pacific rim) Regatta, so there will be land yacht pilots there from Japan, New Zealand, Australia, etc. </p>
<p>It is not only a great event, but it is the same time of year that the current land record of 116 mph was set &#8211; at the same location, 10 years ago.</p>
<p>Believe it or not, I have been trying to beat that record every year, at different locations around the world since then, but opportunities are very few are far between. </p>
<p>Let’s hope it is a 10 year weather cycle!</p>
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		<slash:comments>2</slash:comments>
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		<item>
		<title>Video blog of 1st sail on Canyon Ferry</title>
		<link>http://blog.greenbird.co.uk/2009/01/28/video-blog-of-1st-sail-on-canyon-ferry-lake/</link>
		<comments>http://blog.greenbird.co.uk/2009/01/28/video-blog-of-1st-sail-on-canyon-ferry-lake/#comments</comments>
		<pubDate>Wed, 28 Jan 2009 12:50:45 +0000</pubDate>
		<dc:creator>Richard</dc:creator>
				<category><![CDATA[Ice Record]]></category>
		<category><![CDATA[Video]]></category>
		<category><![CDATA[Canyon Ferry Dam]]></category>
		<category><![CDATA[ice]]></category>
		<category><![CDATA[Ice craft]]></category>
		<category><![CDATA[Montana]]></category>
		<category><![CDATA[speed]]></category>
		<category><![CDATA[testing]]></category>

		<guid isPermaLink="false">http://blog.greenbird.co.uk/?p=332</guid>
		<description><![CDATA[After looking at the GPS, I am really not to worried about the crafts performance, and will be bringing you data on this shortly. The real problem is the ice surface.
Have a look at this video, which hopefully explains it a little better.
				
				
The problem with going fast is that you need to be able to [...]]]></description>
			<content:encoded><![CDATA[<p>After looking at the GPS, I am really not to worried about the crafts performance, and will be bringing you data on this shortly. The real problem is the ice surface.</p>
<p>Have a look at this video, which hopefully explains it a little better.</p>
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<p>The problem with going fast is that you need to be able to support and transfer very large forces into the ice, and to do this the machine needs to be strong, and relatively stiff. When you need to absorb bumps over a range of speeds, this presents huge problems for a structure carrying high loads and a sophisticated suspension system is required. However, active controls are not allowed and there are also issues with the size and frequency of the bumps. The skate weighs over 50 kg and it needs to move at at a speed of up to 50 Hz over maybe 2-3 inches. To save confusing everybody, I won&#8217;t go on , but this challenge is nothing short of impossible. Imagine driving your car with steel wheels and no tyres over concrete speed bumps at irregular intervals at 120 mph.</p>
<p>Walking over the surface at slow speeds, you really don&#8217;t get a proper picture for the size and frequency of the ice bumps and I had been way too optimistic of what the natural flex of the main beam would accommodate. The end result is that the craft suffered a couple of failures during the first sail, that I was unaware of at the time.</p>
<p>Firstly the main sail bearing for the top section failed. This was a huge surprise and has performed perfectly for thousands of miles on land. It is a big industrial, self aligning machine bearing, that is rated for over 300 kg of axial load. The sail only weighs 25 kg, so well within design range. Secondly, the counter weight on the top section had bent very slightly down, meaning I could not extract it from the composite sleeve in the wing. This tube supports a lead weight in the end and was designed for dynamic forces of 10G (ten times gravity) to cope with any accelerations. However, it yielded.</p>
<p>Both these failures point to vertical accelerations of over 10G at the top of the mast, which is completely unacceptable. It felt rough from the cockpit, but not that rough!</p>
<p>Adding to the problems the lake had some more snow over the last day or two, which have exaggerated the drifts, extending the time that it will be out of action.</p>
<p>For now we have packed the craft up and will be repairing the two problems (easy fixes), but I am uncertain when we will be able to run again.</p>
<p>The bottom line is that to go really fast, the surface needs to be flat and this only happens at the start of the season, after first freeze and before any snow, or at the end of the season in March, when the surface melts, before the ice breaks up. My gut feeling is that the only opportunity is going to be after first freeze in December, but we will see. If the ice does get better this season, we will be back, but if not, then I guess I will be sitting by the lake in December while it is still water, waiting for the freeze.</p>
<p>If it was easy, everyone would do it, right?</p>

<a href='http://blog.greenbird.co.uk/2009/01/28/video-blog-of-1st-sail-on-canyon-ferry-lake/dsc07058/' title='Failed bearing'><img width="150" height="112" src="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/dsc07058.jpg" class="attachment-thumbnail" alt="Failed bearing" title="Failed bearing" /></a>
<a href='http://blog.greenbird.co.uk/2009/01/28/video-blog-of-1st-sail-on-canyon-ferry-lake/dsc07062/' title='Closer inspection'><img width="150" height="112" src="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/dsc07062.jpg" class="attachment-thumbnail" alt="Closer inspection" title="Closer inspection" /></a>

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		<slash:comments>10</slash:comments>
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		<title>First sail at speed</title>
		<link>http://blog.greenbird.co.uk/2009/01/24/first-sail-at-speed/</link>
		<comments>http://blog.greenbird.co.uk/2009/01/24/first-sail-at-speed/#comments</comments>
		<pubDate>Fri, 23 Jan 2009 23:10:47 +0000</pubDate>
		<dc:creator>Richard</dc:creator>
				<category><![CDATA[Ice Record]]></category>
		<category><![CDATA[ice]]></category>
		<category><![CDATA[Ice craft]]></category>
		<category><![CDATA[Montana]]></category>
		<category><![CDATA[speed]]></category>
		<category><![CDATA[testing]]></category>

		<guid isPermaLink="false">http://blog.greenbird.co.uk/?p=314</guid>
		<description><![CDATA[Yesterday saw the first wind at Canyon Ferry, in the 2 weeks that I have been here. As a trough moved through the area, the winds picked up at about midday, to 15 mph, then steadily grew, peaking at around 30 mph by 17:00.
I got the Greenbird ready, tested the parachute deployment, strapped in the [...]]]></description>
			<content:encoded><![CDATA[<p>Yesterday saw the first wind at Canyon Ferry, in the 2 weeks that I have been here. As a trough moved through the area, the winds picked up at about midday, to 15 mph, then steadily grew, peaking at around 30 mph by 17:00.</p>
<p>I got the Greenbird ready, tested the parachute deployment, strapped in the GPS and camera equipment (2 mini HD cams, one pointing forwards, the other backwards) and set off.</p>
<p>For all of these tests, you must remember it is essentially the same machine that I ran on land, both on tarmac in the UK and dirt in Nevada, so we have good performance figures to compare against. The initial acceleration was impressive and better than on land, reaching 40 mph without me even touching the sail controls. From then on a slight pumping of the wing sheeting pressure system pulled in the wing and we were off. But it very quickly became apparent, that the ice is just way too rough, despite my optimistic idea that we had enough room, it was not the case.</p>
<p>After a few slow circuits I was confident everything was working so pushed a little harder, peaking at 73 mph, but the ride was nothing short of &#8216;brutal&#8217;. Even with the &#8216;plank&#8217; flexing nicely, hitting a 3inch ice bump at 70 mph in a yacht weighing 850kg, is a rough experience. The yacht bounces around, skips sideways very slightly while it regains its &#8216;edge&#8217; then off again, pretty wild accelerations in all directions. Shakes the boat to pieces and is definitely not &#8216;fast&#8217;. The problem is that with these bumps every 30 feet, there is no let up. The further offshore you go the worse the bumps (actually old snow drifts) get, so I was confined to a narrow strip at the edge of the lake. However, even in these rough conditions, the Greenbird handled very well, good control of direction and power, no failures, which is a testament to the structure and overall strength.</p>
<p>This picture of my track, overlayed on the lake surface shows how little room we have to play with.</p>
<div id="attachment_321" class="wp-caption aligncenter" style="width: 263px"><a href="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/22jan09.jpg"><img class="size-medium wp-image-321" title="Track overlay" src="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/22jan09.jpg" alt="Track overlay" width="253" height="300" /></a><p class="wp-caption-text">Track overlay</p></div>
<p>It was so rough, that BOTH onboard cameras malfunctioned, capturing only the first few seconds of each trip. This was a real shame because it was a pretty spectacular ride from the cockpit.</p>
<p>I was initially disappointed with the speed, as the yacht has gone a lot faster on land, but once the wind and GPS data was downloaded, I began to understand the numbers. Due to the confined space, I could only sail at close angles to the wind (into or away from it) and not perpendicular, which is fastest. The wind was coming from the prevailing direction at 320 deg. The fastest speed was 73 mph sailing at 51 deg into the true wind, is about 22 &#8211; 24 mph of wind. Now this is actually pretty respectable and proves record speeds are easily achievable sailing at the optimum angle to the wind of 110 deg. I will analyse the data over the next few days and present some performance predictions next week.</p>
<p>So what can we conclude from all this. Unless we encounter some unexpected grip problems at high speed, we easily have the performance to destroy all current records, but you do need almost perfect ice, which it is far from right now. Worse still it is not going to get better until they have a big thaw towards the end of the season (March), so we will have to make a plan whether we hang around for a little more testing experience, or realise there is nothing more to learn, until the ice is better, not decided yet.</p>
<p>I will be analysing the data over the next few days and will report back shortly. I also had GPS recorders on the other, conventional ice boats sailing in the same conditions, so it will be interesting to compare the data. Finally I will try to piece together the bits of the video that are usable, and get this posted.</p>
<p>The speed record: (note 30 Km sailed)</p>
<div id="attachment_326" class="wp-caption aligncenter" style="width: 310px"><a href="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/speed-graph.jpg"><img class="size-medium wp-image-326" title="Greenbird speed graph" src="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/speed-graph.jpg" alt="Greenbird speed graph" width="300" height="87" /></a><p class="wp-caption-text">Greenbird speed graph</p></div>
<p>This is the wind record from our on site weather station:</p>
<div id="attachment_327" class="wp-caption aligncenter" style="width: 310px"><a href="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/wind-record.jpg"><img class="size-medium wp-image-327" title="Wind record" src="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/wind-record.jpg" alt="Blue is 1min avg, Purple is peak gust speed" width="300" height="201" /></a><p class="wp-caption-text">Blue is 1min avg, Purple is peak gust speed</p></div>
<p>This is the nice ice, close in, and it certainly was smooth and fast in this area, but unfortunately it is just way too small:</p>
<div id="attachment_325" class="wp-caption aligncenter" style="width: 310px"><a href="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/ice_yachts.jpg"><img class="size-medium wp-image-325" title="Ice yachts on nice ice" src="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/ice_yachts.jpg" alt="Ice yachts on nice ice" width="300" height="225" /></a><p class="wp-caption-text">Ice yachts on nice ice</p></div>
<p>The rough ice further out&#8230;&#8230;</p>
<div id="attachment_324" class="wp-caption aligncenter" style="width: 310px"><a href="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/bumpy_ice.jpg"><img class="size-medium wp-image-324" title="Bumpy Ice" src="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/bumpy_ice.jpg" alt="Bumpy Ice" width="300" height="225" /></a><p class="wp-caption-text">Bumpy Ice</p></div>
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		<slash:comments>6</slash:comments>
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		<item>
		<title>Video blog of Greenbird on Ice</title>
		<link>http://blog.greenbird.co.uk/2009/01/22/video-blog-of-greenbird-on-ice/</link>
		<comments>http://blog.greenbird.co.uk/2009/01/22/video-blog-of-greenbird-on-ice/#comments</comments>
		<pubDate>Thu, 22 Jan 2009 11:23:28 +0000</pubDate>
		<dc:creator>Richard</dc:creator>
				<category><![CDATA[Ice Record]]></category>
		<category><![CDATA[Video]]></category>
		<category><![CDATA[Canyon Ferry Dam]]></category>
		<category><![CDATA[ice]]></category>
		<category><![CDATA[Ice craft]]></category>

		<guid isPermaLink="false">http://blog.greenbird.co.uk/?p=306</guid>
		<description><![CDATA[I thought I would try a little video blog experiment while I am waiting for the wind. Let me know if you want more  
				
				
]]></description>
			<content:encoded><![CDATA[<p>I thought I would try a little video blog experiment while I am waiting for the wind. Let me know if you want more <img src='http://blog.greenbird.co.uk/wp-includes/images/smilies/icon_smile.gif' alt=':)' class='wp-smiley' /> </p>
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		<slash:comments>8</slash:comments>
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		<item>
		<title>Waiting, waiting</title>
		<link>http://blog.greenbird.co.uk/2009/01/19/waiting-waiting/</link>
		<comments>http://blog.greenbird.co.uk/2009/01/19/waiting-waiting/#comments</comments>
		<pubDate>Mon, 19 Jan 2009 09:55:17 +0000</pubDate>
		<dc:creator>Richard</dc:creator>
				<category><![CDATA[Ice Record]]></category>
		<category><![CDATA[ice]]></category>
		<category><![CDATA[Ice craft]]></category>
		<category><![CDATA[wind]]></category>

		<guid isPermaLink="false">http://blog.greenbird.co.uk/?p=294</guid>
		<description><![CDATA[The Greenbird ice craft is now in record ready shape, but alas, one thing is missing, yep, wind! A huge high pressure is dominating north west USA, bringing clear skies and very light winds. The good side to this is that temperatures are above normal during the day and often creep into the +0 deg [...]]]></description>
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<a href='http://blog.greenbird.co.uk/2009/01/19/waiting-waiting/dsc07032/' title='Waiting for wind'><img width="150" height="112" src="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/dsc07032.jpg" class="attachment-thumbnail" alt="Waiting for wind" title="Waiting for wind" /></a>
<a href='http://blog.greenbird.co.uk/2009/01/19/waiting-waiting/image001/' title='Whitebird'><img width="150" height="112" src="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/image001.jpg" class="attachment-thumbnail" alt="Whitebird" title="Whitebird" /></a>
<a href='http://blog.greenbird.co.uk/2009/01/19/waiting-waiting/image002/' title='Icicles'><img width="150" height="112" src="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/image002.jpg" class="attachment-thumbnail" alt="Icicles" title="Icicles" /></a>
<a href='http://blog.greenbird.co.uk/2009/01/19/waiting-waiting/image003-2/' title='Frozen wing'><img width="150" height="112" src="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/image003.jpg" class="attachment-thumbnail" alt="Frozen wing" title="Frozen wing" /></a>
<a href='http://blog.greenbird.co.uk/2009/01/19/waiting-waiting/image004-2/' title='Warm glow'><img width="150" height="112" src="http://blog.greenbird.co.uk/wp-content/uploads/2009/01/image004.jpg" class="attachment-thumbnail" alt="Warm glow" title="Warm glow" /></a>

<p>The Greenbird ice craft is now in record ready shape, but alas, one thing is missing, yep, wind! A huge high pressure is dominating north west USA, bringing clear skies and very light winds. The good side to this is that temperatures are above normal during the day and often creep into the +0 deg C region, so this melts the surface ice, gradually making it smoother. In fact, the ice is in great shape and getting better by the day, so when it does blow, we will be ready! It looks like the current weather system will change around Thursday, with a trough approaching from the North east Pacific. This will lower temperatures increase cloud cover and bring the chance of wind, as well as snow, of course!</p>
<p>On the craft, I have improved the steering control with a more robust hydraulic steering system from Teleflex, and also added yet another GPS, with a graphical display, showing the track and speed in real time. This is very useful, because when travelling at high speed, so close to the ice, it is often hard to tell how close you are to obstacles or the edge of the lake. We now carry a total of 6 independent GPS systems on board, each logging the speed and position at frequencies between 10 and 1 Hz.</p>
<p>I have also added a parachute, which can be used in emergencies or to just to aid stoping. Slowing from max speed should be relatively easy, but actually slowing from 50 mph to zero can be much harder. With such a low parasitic drag and the wing always wanting to drive forward, the parachute may be necessary to get the craft to come to a complete stop. As yet, all hypothetical, but we will soon find out if it is needed.</p>
<p>Would be nice to go out and test it all now!</p>
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