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Along with the very exciting news of NauticEd joining forces with Lagoon Catamarans to bring Catamaran Sailing education to the market, we have announced our latest update to the Catamaran Sailing Confidence Course.
The interactive Catamaran Sailing Confidence Course is available online in browser and PDF format and as an App eBook from the Apple iTunes Store.
It is organized in three modules:
Anchoring and Maneuvering
and will give the student ample education on how to convert their monohull sailing experience into confident operations of how to sail a catamaran.
Module 2 features an interactive game which has the student maneuvering the Catamaran in and around a marina using the dual throttle controls.
View our about the Catamaran Sailing Confidence Course video.
When you take the Catamaran Sailing course you will also take a test associated with each module. Upon passing the tests, the Catamaran sailing knowledge endorsement will be added to your NauticEd Sailing Certification. This is viewed by yacht Charter Companies world wide and is used to determine if you are a worthy client to consider for a Catamaran Charter.
Catamaran Sailing Confidence as an iPad App eBook
Both the online version and the Apple App Catamaran Sailing eBook version feature hi resolution photographs and embedded animations to give the student a rich and compelling educational experience. This is the only eCourse of it’s kind in the world and is jam packed full of Catamaran Sailing tips and tricks to help you convert from a monohull with high confidence.
The online version of the Catamaran Sailing Course has the test embedded at the end of each module. When you do the iPad version, only the content is supplied and you will be given a promocode which represents the cost of the eBook. You use this promotion code to buy the online course and you take the test online. OR you can use the NauticEd iPad testing App to take the test – but this must still be after you have bought the course online. You may need to tap “refresh test questions” on your iPad App this makes the App check the database to ensure you have bought the test.
The PDF downloadable version is available to the student after the Catamaran Sailing course is purchased online
The investment in the Catamaran Sailing Confidence Course is only $27 and considering that the knowledge will vastly enhance your experience, the investment is well worth it.
So how do they do it? I was watching it on Sunday – the wind was at about 15 knots, yet the boats achieved 43 knots angling downwind and 25 knots angling upwind. Wow – this is the most impressive thing in yachting. The engineering design effort and atmosphere over the past three years must have been intense, ground breaking and so innovative. This is the stuff that engineers and yachties live for. Even if it is to sit back and just watch (eyes wide open).
Back to the question – how do they do it? Now that we’ve been seen to remove the drag factor almost entirely by introducing the foils and getting the hull out of the water, we’re seeing that the limitation on boat speed is not hull design or even wind speed as one might have thought. It comes down to the angle that a boat can go into the wind.
First consider this – As the boat goes faster and faster, the wind that the boat feels “shifts forward”. Every one says that but how? what does that mean? Here take a look at this:
It is the wind shifting forward as a car accelerates. The wind that the car feels is the shifted wind – called the apparent wind. “Apparently” this is what the car feels. So, same on a boat. The boat feels the new wind generated by it’s own speed. Unless it is stopped dead in the water, a boat will never feel the actual true wind. But the limiting factor is how much forward force can the winged sail garner out of the wings from the angle between the boat heading and the direction of the apparent wind. That angle can never be zero else the boat would be moving straight into wind and that’s not possible under these universal laws. The lift or forward component of the force to drive a boat forward relies on this angle. In traditional sailboats, this angel is about 30 degrees off the apparent wind angle.
As an extreme example, ice sailing sleds with vertical wings and only thin blades touching the ice can achieve an 11 degree angle off the apparent wind. Airplanes with an asymmetric wing shape can gain lift with around 5 degrees off the airflow. Now with hydrofoils mounted on the Americas Cup AC72 sailing catamarans, we’re seeing sub 20 degrees off the apparent wind.
With few rudimentary calculations then and with out calling the design teams at Team New Zealand or Oracle I calculated that the apparent wind must be about 19 degrees on a downwind angle and about 16 degrees on upwind. This was done by observing their tacking and gybing angles and plugging it all into the sine and cosine formulas. These formulas solve for the following obtuse triangle. We observed the true wind speed, the boat speed and the angle off the wind and thus we solved for the remaining.
Here it is for the AC72 heading downwind
AC72 Americas Cup True vs Apparent Wind – Dowwind
And here is is for the AC72 heading upwind
Americas Cup AC72 True Vs Apparent Wind – Upwind
Given these formulas, there was no other solution than to come up with about 19 degrees of apparent wind heading downwind and 16 degrees apparent wind heading upwind. You might have also observed how tight in the sails were trimmed in the “downwind” heading. They were tight – even the non-winged headsail. This means the AC72’s were on a close haul heading downwind. Messes with your mind doesn’t it.
Now there are a lot of other factors that play into all this like sideslip, tide, etc and I’ve not done those calculations so please consider this as completely rudimentary. I only have a Masters in Engineering – and you can bet a whole pile of dimes that a PhD guy will come back to me on a full explanation. With all the equations and diagrams – please do – I’ll publish it here – so long as it’s not too complicated. What I’ve attempted to do is explain the question presented above. How does an America’s Cup AC72 go faster than the speed of the wind?
Here is an animation of the AC-72 performing tacking and gybing maneuvers. Watch the wind vectors through the maneuvers and also watch the boat speed increase as it bears away.
BUT WAIT – Look at the Apparent Wind!
What I’m seeing here is that the apparent wind vector is shorter than the boat speed. How can that be – the apparent wind speed less than the boat speed? Huh? Well actually who cares? Wind is just a force – it does not matter its speed. You now have to release your self from the boundaries of old monohull sailing with big hull drag. The only factors we are now dealing with is drag from the hydrofoils and the force that the wings can eek out of the wind it sees. As the apparent wind gets closer and closer to the front of the boat the accelerating force reduces. As the boat speed increases, the drag force increases. The boat will stop accelerating only when the drag force = the accelerating force.
The following animation shows the drag force increasing with speed and the accelerating force from the wings reducing. Note that there is a step jump down in drag force as the boat begins to hydrofoil. Had the drag force equalled the accelerating force before the boat hydrofoiled then the boat would not continue to accelerate.
So there you have it. With limitations on our minds now removed – you can see that boat speed can just keep on increasing and increasing until the forward component of the force from the wings equals the drag force on the boat. As the boat gets closer and closer to the apparent wind angle the forward force component reduces. True wind speed matters only in that it helps to get the boat up on the foils but at high boat speeds, by looking at one of the vector diagrams above, an increase in true wind speed will only marginally help to increase the apparent angle which marginally increases the forward forces. The biggest revolution has come from the introduction of the wing being able to gain lift from closer angles to the apparent wind AND in a massive reduction in drag. Think about drag next time you’re towing a dinghy behind your cruising boat on a close haul. This requires an increase in force and the only way then to maintain speed is to bear way – whoops.
With all this, I couldn’t help it – I’ve thrown in a basic (very basic) interactive animation of AC72 going around the course showing the above diagrams at strategic points around the course.
The Electronic Navigation Course is Laid out in Eight Modules
Electronic Navigation Course
Module 1 emphasizes that electronic navigation is an aid to the good sailor’s senses but can not replace them.
Module 2 introduces and brings back some of the basics that you should already be familiar with in regards to navigation.
Module 3 is an in-depth discussion of wind. In particular it delves into the calculation of true wind and shows how important true wind direction is when navigating.
Module 4 is all about boat speed. How to navigate using optimum speeds and how to find your best course to achieve your destination in the fastest time. We define velocity made good on course and velocity made good upwind.
Module 5 prepares you for the shotgun of jargon that will be delivered in module 7.
Module 6 introduces technologies such as AIS, RADAR and Weather GRIBS and electronic chart overlays.
Module 7 is a step by step walk through of a real GPS chart plotter unit. You’ll gain the confidence, working knowledge and user experience, through various animations, to fully work a chart plotter device and apply this to your sailing navigation.
Module 8 will round everything out so that you’re confident in your ability to navigate using electronic instruments.
Here is a youtube post by one of our talented students who gets a perfect score playing our Catamaran Maneuvering game. I’m guesssing a few hours were involved here but I’m pretty sure that given this amount of maneuvering experience in real life, Andrew would be an expert at maneuvering a catamaran around in a marina.
Here Andrew expertly maneuvers the catamaran through out the marina without one bonk or scratch. The game can be found online and is free to play when you log into NauticEd. The game is as realistic as possible and is controlled using the two throttles as would be found on a real catamaran. Play this game and you’re a long way to gaining some valuable experience for when you really get on a Catarmaran on your next sailing vacation.
In this article, we’re really talking about bareboat chartering of a Catamaran sailing boat on a sailing vacation.
Of the dozens of flotilla trips I’ve lead to the Mediterranean, Pacific and the Caribbean, I’d say it was about 50/50 between monohull charter and catamaran charter. Chartering in the Mediterranean, however tends to be more monohulls because of the tight space available in the marinas. Not to say that you can’t do a catamaran charter in the Mediterranean but if you want to, you should plan on booking ahead far in advance ( perhaps 1 year).
Sailing a Catamaran on a yacht charter sailing vacation in the Caribbean is much easier and more prevalent. Still, these days with the popularity of Catamaran Charter, you should still book at least 6-9 months in advance.
Catamaran Charter in Belize
A good money saving tip here is to get on the email list of the catamaran charter companies. When they’re having a special – they’ll be certain to let you know. One week either side of a low/mid/high season could save you thousands.
There’s lots of advantages to a catamaran sailing boat over a monohull on a sailing vacation. First off, you don’t spill your rum drink ( I say Rum drink here now because of our newly formed alliance with Mount Gay Rum who sponsor the Sailing Spoken Here website and community. Mount Gay Rum has made NauticEd their exclusive Sailing Education partner (slight pat on the back to the NauticEd team)). Whilst sailing a catamaran, even on a beat to windward, you don’t heel over. You can just set your drink down and it won’t slide off the table.
No heeling over while sailing a catamaran
New sailors like catamaran chartering again because of the no heeling factor. Funny – I can’t understand it – but new sailors don’t like spending all day hanging on for dear life. Go figure that one out.
True monohull sailors tend to scoff at sailing a catamaran but – we say get over it. Sail a monohull at home and do a catamaran charter on holiday with your family and mates. It’s not about you – it’s about everyone on the boat having a really good social fun time. Apologies for the admonishment but ….
One of the interesting differences about sailing a catamaran is that because they don’t heel over, you have to be especially weary about the loads on the rig. On a monohull, as the boat heels over, the load stays about the same because there is less sail area presented to the wind. When you get too much heel, it’s a signal to reef the sails. When sailing a catamaran, the loads just increase as the wind strength gets higher. Usually there is a chart that comes with the catamaran to show when to reef according to the wind strength. You should identify this chart before you leave the dock.
You can also twist out the top of the sail to reduce the wind load on the sails. You do this by pulling the traveler to windward and letting out on the mainsheet (with the boom vang loosened). This allows the boom to rise up and twist out the top of the mainsail. Thus forces aloft are reduced and consequently the forces on the rig. BUT you should reef the sails when you reach the windspeeds shown in the reefing chart else risk the rig coming down.
The traveler on a catamaran is so wide that this becomes a more noticeable effect over many monohulls. In the photo below you can see how the sail aloft is pointing at a much different angle than the sail section near the boom. Thus the bottom of the sail is doing the powering with a vastly reduced heeling (rig breaking) moment.
catamaran sailing: sail twist out
NauticEd’s Catamaran Sailing Confidence Sailing Course leads NauticEd Sailing Students through the switch over from monohull sailing to Catamaran Sailing. It even has a sailing game that helps the students learn to maneuver and dock a catamaran using the dual engine controls embedded into the catamaran sailing course. And as a reward for reading this blog – we’ll tell you that the Catamaran Maneuvering Game is Free when you set up a free student account with NauticEd. Login now using your facebook account.
We highly recommend (of course) that if you’re going to do a catamaran charter in the Caribbean or Mediterranean, that you take both NauticEd’s Bareboat Yacht Charter Sailing Course and NauticEd’s Catamaran Sailing Confidence Sailing Course.
Sailing a catamaran is pretty easy but there are some nuances that you should know like reefing etc above that you really should learn before you leave the dock.
If you’re thinking about a bareboat yacht charter sailing vacation, invest in the NauticEd Bareboat Charter Master Sailing Certification accepted world wide by most charter companies including The Moorings, Sunsail, BVI Yacht Charters, Sailing New Zealand, Kiriacoulis etc etc.
Last weekend we met up with our friends Chris and Christine Ellsay in Nelson New Zealand. Chris and Chris, with their three kids aged 10, 8 and 6 are sailing around the world and it was refreshing to hear them say – “I don’t know how long we’ll take”. They’re 3 years into it and have made it from the great lakes in Eastern Canada to New Zealand so far. The route has been via the Caribbean, Venezuela, Columbia, Panama, Galapagos Islands, Marquesas Islands, French Polynesia, Tonga and now Kiwiland. (We missed them by a week when we were in Tonga with the NauticEd Graduation Trip in September last year.)
Holding out in New Zealand for the summer while the tropical cyclones pass overhead in the pacific islands, they say they’re returning to the Pacific, starting with Fiji in Late April 2011. Then they’ll decide if to hang another year in the pacific or head off to the top of Ausy through the Indian ocean in 2011 or 2012.
I interviewed Chris and Chris (and the kids) on their experience with a catamaran rather than a monohull for sailing around the world. Their opinion after 10,000 miles is that they would not have done it any other way. The comfort and space was the resounding feedback.
Here’s a short video introducing Stray Kitty a World Cruising Life Style, and Abel Tasman National Park In New Zealand.
Here’s a few pics of Stray Kitty, their 42 foot PDQ Antares 2002 Catamaran.
Stray Kitty in the Nelson Marina
The foredeck at anchor is a great place for a few gins after a hard day sail.
Foredeck of Stray Kitty 42 ft Catamaran
The Kids are being home schooled by Christine and by the sounds of it – they were way ahead of where they should be – good job Christine!
Kids sailing around the world - pretty cool kids
These three kids (my one is the 2 1/2 year old 2nd to right ) are pretty amazing – they fear nothing, do their school work, do as they are told, release the lines on command, know which electrical switches to flick on at the right time – in fact I think they’d make it back to land if mum and dad fell overboard. They’re pretty cool kids and are a delight to spend time with.
Plenty of room inside the catamaran for school work
The Catamaran has heaps of room inside and it’s easy for the kids to do their school work underway because the boat stays flat when sailing.
Stray Kitty is sailing the traditional route around the world following the trade winds. Chris reported that much of their sailing has been downwind and so here he is showing me his much used bowsprit for flying their Gennaker. Oh and by the way – notice the incredible bay that we stayed overnight in – in the back ground in Abel Tasman National Park at the top of the South Island.
The Catamaran Bowsprit
There is plenty of safety gear on board and Chris and Chris are doing it right. Notice all the the MOB gear at the stern of the boat ready to be instantly deployed should anyone go overboard.
The boat has on-board a generator, two alternators and solar panels for powering all the electrical requirements of the boat. The total solar production capability is about 500 watts. Chris says for every thing to maintain with out the use of the generator or alternators – he’d like to have about 1000 watts of solar capacity so they do have to kick on the generator every now and then.
Solar Panels on the hardtop of Stray Kitty
Chris also discussed with me his Internet connections via SSB and his weather information gathering capability. Here he has downloaded a GRIB which is a map forecast of the sailing area we were in. The expected forecast was for 35 knots and they got it right. Out sailing we saw it peak to 36 knots on the wind meter. Made for some fun sailing.
Downloading the Weather GRIB
And the kids loved the bumpy ride that day as you can see here.
High waves making the trampoline a fun place to be
And here’s us busting through the 1-2 meter swell.
Crashing through the waves sailing the catamaran
Over the 4 days we spent with these true ocean sailors, we had a blast (beyond the 36 knotter). We scored some amazing shots of the Able Tasman National park in New Zealand which will be on the next blog. Stray Kitty will be making the passage up to Auckland via the east coast in a few days but first they’ll have to wait for right weather conditions to cross one of the world’s renown rough water ways, the Cook Straight which lies between the North and South Islands. High winds and current can make this one a bit tricky.
We’re pretty jealous of Stray Kitty. One of Chris’ sayings over the weekend was the “we regret in life more things that we don’t do than what we actually do” and this was one of the big reasons they sold their business and set out across the oceans and wow they had some good stories to match.
If you’re thinking about sailing around the world then we’d certainly recommend our more serious NauticEd sailing school sailing lessons associated with the Captain’s Rank, those are Safety at Sea, Storm Tactics, Weather, Sail Trim as well as – if you think a Catamaran might be the way to go – take the Catamaran Sailing Confidence Clinic.
It was great to see this family making fun light work of sailing around the world. It’s certainly got me thinking – any one else?
Torrent Bay - Abel Tasman National Park New Zealand
Next week we’re going to Tonga and the island of Vava’U for a week long NauticEd Flotilla sailing trip amongst the archipelago. After a rainy and relatively cool winter in New Zealand this year its going to be a welcome and fun trip. We’re bareboat chartering three catamarans from the Moorings. 21 adults and 3 three children aged 2, 3 and 6 are coming. Correction that makes 24 children I think by the excitement and way every one is acting so far. We’re looking forward to doing some excellent sailing, fishing, swimming in warm water, snorkeling under the rock wall into Mariner’s cave and maybe have a few lovely glasses of red wine under a warm evening sky. So in light of catamaran sailing then I thought this week we’d review a method of getting a catamaran off the dock when a difficult wind is blowing onto the dock. We needed to use this in the British Virgin Island last year and with some whacky wave action we also had to time it right. It’s just as well we used this method because, with the waves, some serious damage could have occurred.
Using a spring line to get off the dock with a catamaran
The concept is pretty simple and effective. First tie a dock line from the front of the boat to the dock towards the aft. Then turn the helm all the way towards the dock and engage the out side engine in forward. The thrust from the backward wash of water as depicted by the arrow onto the turned rudder plus the force moments from the outer thrust and inner dockline will act to turn the back end of the catamaran out away from the dock. You must position a crew member with a dock fender to hold it between the boat and the dock. When the boat is turned out a significant amount, you can engage reverse but make sure it is more than 45 degrees out, else you can be in trouble with the wind pushing you back onto the dock. Once in reverse, turn the helm the other direction to get the boat moving in the right direction. Wait until the boat is a significant distance away from the dock before you decide to engage forward and swing the boat around otherwise the back quarter of the boat can broadside back into the dock, especially if the wind is strong.
You can apply a little reverse thrust to the dockside engine but keep it so that the tension remains on the dock line. The method of using the dock line rather than just opposing engines turns the catamaran more effectively when operating close to the dock because the dockside front quarter is essentially trapped thus a simple rotation won’t work.
Make sure that the dock line is arranged so that it is tied to the boat then looped 1/2 turn around the dock cleat then back to the boat. In this manner the crew member managing the fender can, at the right time, release one end of the dock line and pull it back around the dock cleat to retrieve it – all the while standing on the boat as it pulls away from the dock. Make sure the end has no knots in it. Also ensure the crew member understands not to release the dock line too early because they will not be able to hold against the thrust force.
Obviously this concept works similarly for monohulls.
Full concepts of maneuvering sailboats under power, sailing rules and catamarans are covered in these two NauticEd sailing courses.
Early to rise in Savannah Bay – and a swim to shore. Again, this morning we spent a few hours on the beach at Savannah bay snorkeling, playing beach bats, and strolling along the 750m long beach.
We then set sail for Spanish town again were we picked up more ice. We discovered a free wifi service in Spanish town and so a few or us down loaded emails for the weeks work to come.
Inside Spanish Town harbor, I spent about 10 minutes teaching catamaran maneuvering under power techniques to one of the crew who is going to charter a catamaran on a sailing vacation in Corsica in May next year. Under normal circumstances in Spanish Town Harbor this would be impossible but due to extremely light traffic in the summer months we were able to do this. The biggest difference that he learned was that when maneuvering a Catamaran, you don’t need water flowing over the rudder to gain maneuverability like a monohull. With a catamaran, the slower you go the better. And so the lesson was more about puling the throttles back and using the correct setting of the forward and reverse on the engines and to watch the relative movement of the boat and adjust the throttles to match what you want – always electing to reduce power (if possible) rather than to increase power on the opposing side. For more information on maneuvering a Catamaran under power see the Catamaran Sailing Confidence Clinic.
Additionally – early in November 2009 we’ll be releasing the NauticEd Catamaran Maneuvering Under Power Game. If you’re wanting to learn to sail a catamaran then this is the game for you – it’s fun.
Catamaran Maneuvering Under Power Game
We then exited the marina and set sails for Salt Island, the agreed upon rendezvous point with the other Catamaran Annie K. We had decided to go ashore there and collect some table salt from te salt ponds and enjoy the beach. The wind was cranking perfect at about 15 knots out of the east and so we enjoyed a really nice and fast broad reach to Salt Island.
Unfortunately, upon arrival, Annie K waved us off reporting that the island had been inhabited by absolute pigs with broken glass all over the beach, fire pits everywhere, trash and polluted salt ponds. Almost like people living there did not want others to share in any island beauty and elected instead to spoil it for everyone inclusive of them selves. So – I guess they achieved success in that we did not drop anchor and instead moved over to the easterly neighboring island, Cooper Island.
Cooper Island BVI's
Manchioneel Bay Cooper Island is fantastic. Although in low season the restaurant is only open for lunch. However there are lots of mooring buoys there and a really nice little beach. The wind was out of the east and so the conditions were calm and protected.
Some of the guys (self inclusive) found a coconut and broke out into a game of modified touch rugby. After about an hour, with a few injuries sustained we all retired back to the boats.
We elected to spend the night in Manchioneel Bay because of the short 6 nautical mile sail in the morning back to Road Town.
If you want to learn to sail a large catamaran, this is the sailing course for you.
Here is an excerpt from the course.
And if there wasn’t enough advantages to sailing a catamaran here is another.
The mainsail traveler on a catamaran is significantly longer than on a cruising monohull. Thus you can take real advantage of this. The mainsail can now be adjusted in 2 different ways: using the traveler line or by adjusting the mainsheet.
When sailing closed hauled on a catamaran in heavier air, move the traveler up wind (on the opposite side of the sail) and let off on the main sheet. This will allow the boom to rise a little and “twist out” the top of the sail. Twisting the sail allows you to let some of the top part of the sail “deflate” in case of slightly stronger winds. In light air, make sure that the top of the mainsail is not “loosing air” meaning, keep the traveler close to the center and tighten the mainsheet pretty good to make sure the main cannot open up at the top.
As soon as the breeze kicks up, bring your traveler up a bit more and ease the mainsheet so that the boom does not come past center point.
Lagoon 420 with traveler pulled to windward
Once out sailing you’ll be able to dispel one of the biggest “myths” surrounding catamarans because modern cats actually do do point pretty well!!
The flatter the water, the better they will point and it’ll be possible to sail in the high 30’s degrees off the wind and if you cat has the genoa tracks up on the coach roof, you will have a nice tight sheeting angle allowing you to go upwind comfortably.
As soon as you bare away from the wind slightly, you will want to bring the mainsail traveler down to leeward and start easing the mainsail (similar to a monohull).
Catamaran sailing on a reach
The Catamaran Sailing Confidence clinic retails for $39 but for a limited time it is priced at $27. Please enjoy.