Outremer 5X hull number 2, MOANA is in Fiji. I caught up with the owner Urs Rothacher this week to see how things have been going. I’ve been following Moana with interest for some time because up to this point, she’s the 5X that has traveled the furthest, so I was interested in learning how the voyage was going.
Urs purchased Moana 1 year ago, and is planning on ending his voyage in New Zealand in October this year, so he’s putting her up for sale soon, and will deliver her to a new owner anytime between July and October in either Fiji, Vanuatu, New Caledonia or New Zealand. Here’s more information about Moana along with details on how to conact Urs.
The original owner of Moana was Johan Salen, who along with his wife are veterans of multiple Volvo Ocean Race campaigns, so both very accomplished sailors. They sailed Moana with their young son from La Grande Motte, to New Caledonia where they sold her to Urs. Here’s the post I wrote in 2015 after talking with Johan about his experiences crossing the Pacific on a 5X. After purchasing Moana, Urs continued on to sail the east coast of Australia and then back across the Pacific to Fiji along with his wife and three young boys.
There are a couple of things that stand out for me about this particular 5X and the two families that have owned and sailed her.
- Moana is a 5X that is well configured for short handed sailing. I like the way that Johan configured Moana. He knew that she would be sailed mostly either single-handed or with a crew of just two people. He kept the rig and sail controls simple and efficient, and has provided the best validation to date that the 5X is truly a boat that can be sailed by a cruising couple alone. And although it’s tempting to dismiss this claim due to the exceptional abilities of her original Volvo Ocean Racing owners, Urs and his wife (who are experienced sailors, but still normal humans) confirm that regular folks can handle a well configured 5X.
- Moana is a sailors boat, without a lot of the heavy, complicated (and expensive) options that some of us have chosen. All 5X boats are comfortable, and Moana is no exception, but some of the more elaborate items have been avoided to keep her light, easy to sail, and easy to maintain. No air conditioning, no generator, single wheel helm. And some nice options well suited to shorthanded ocean sailing, cutter rig for simple and efficient headsail changes, watermaker with high and low power modes, redundant auto-pilots, oversized solar array and so on.
I like this boat a lot, and the fact she is already in the pacific is a great opportunity for someone that wants to cruise this region, but doesn’t have the time available to sail a 5X from France to Tahiti before they can begin their pacific cruising program. Urs hasn’t listed Moana for sale yet, so if you’re interested, you have a great opportunity to get her before she goes on the market.
Here’s an Article about Moana that was recently published in the Australian Multihull World magazine.
When we purchased Wildling, I didn’t order a spinnaker because I wasn’t sure if we would need one, and if we did, what type and size we should get. I’m glad I waited, because now that we have sailed our boat for a year, I have a better idea of what I want a spinnaker to do for us. So this month I went through the process of selecting our spinnaker.
Although Robin and I have sailed many miles with a spinnaker on our Catana 471, I really enjoyed learning more about spinnaker design during this process, and I thought I would share some of that information in this post. I would like to thank Jean-Pierre at Outremer (designer, test pilot, and catamaran guru), Nick at Doyle Sails UK, and Volker (who’s 5X is now under construction and will be launched later this year) for sharing their experience and advice.
First a bit of theory: When sailing to a downwind destination in a catamaran, particularly a fast one, we really want to sail on a reach (90-130 degrees AWA), because it’s much faster than sailing deep downwind. Once the angle starts to get more than 130, things begin to slow down to a point where at 150-160, a reaching sail isn’t much use. On a performance boat, as we sail higher (further towards the wind), the boat accelerates and the apparent wind angle moves further forward, which makes sailing a reach very effective, and even though it might be at an angle to the destination, requiring us to travel further by gybing back and forth to stay on course, the extra speed means it’s still the fastest way to get there.
On a technical note: this technique of creating apparent wind is what allows true performance catamarans to move the apparent wind forward of the beam and create speeds well in excess of the true wind speed. take a look at the Americas Cup multihulls that sail at boat speeds close to 40 knots for a demonstration of this.
So every boat should have a downwind reaching sail, which for us, is our Delta Voiles, Code-D gennaker, and you would think that since reaching is the fastest way to get downwind, then that’s the only downwind power sail you need! Well, perhaps… if you’re a racing sailor, then yes, reaching is the way to go. But it takes a lot more work and attention from the crew. You have to trim the angles just right, compensate for wind shifts and watch things carefully. But when cruising, our objectives are different to a racing sailor. What we want is low-stress, comfortable, and fast enough.
So what’s fast enough? I’m sure this is different for everybody, but on Wildling, our target speed range is 9-12 knots. If we’re under 9, I’m working to get us more speed, either by sailing different angles, changing sails, or dialing in the trim. If we’re over 12, then I’m going to start reducing sail to slow us down. There’s no extra benefit to us from sailing a reach and doing a bunch of gybing if we could go fast enough, and more comfortably, on a direct course.
We’re going to be sailing Wildling back home to Australia, a voyage that involves may thousands of miles downwind in the tradewinds, that are often blowing at 15 to 25 knots. It would be ideal if we could turn the boat downwind, set our sails for our “fast enough” speed and not have to constantly mess with the sail trim. That’s where the spinnaker comes in. With a spinnaker, we can sail deeper downwind angles than the limit of our Code-D. But which type of spinnaker should we buy?
There are two types of spinnaker: asymmetric and symmetric, with the asymmetric being the most common spinnaker on a cruising catamaran. Asymmetrics are more like a gennaker, in that they have a different length luff, and leech, but they have a lot more curve in the luff than a gennaker, which allows the luff to twist around to windward and generate power at a deeper angle. They are good for deep reaching, usually up to about 150 degrees, and they can get deeper still if the tack is moved to the windward hull. They’re good because they are versatile, and if you don’t have a gennaker, and want only one downwind power sail, then the asymmetric is the way to go. There are a couple of problems with running deep angles on an asymmetric though. Running deep is not their optimum power zone, and in order to gybe, you have to first douse the sail, move the tack to the other bow, gybe the boat and then rehoist the sail. Some folks rig a system of lines to move the position of the tack between the bows, which saves some of the work when gybing, but depending on the amount of wind, it’s usually safest to douse the sail and rehoist.
Since we have a Code-D, we’re looking for our spinnaker to fill in the 140 to 180 degree angle range, and that is the domain of the symmetric spinnaker. Symmetrics are made to run deep, and gybing is essentially automatic, because they just float around the front of the boat onto the new point of sail, with a few tweaks on the control lines. No need to douse and rehoist.
We decided to get a symmetric spinnaker for Wildling, so the next step was to figure out the size, cut and type of sailcloth for the sail. For our tradewind ocean sailing we want to be able to handle situations where the wind builds more quickly than we expected, and we don’t want the spinnaker to tear if it gets hit by a 25 knot gust. We also don’t want it so big that we can’t get it down in a breeze.
There are many excellent sailmakers that can make a great spinnaker. We chose Doyle sails, mainly because I’ve used their sails before and know they are well made, and Doyle was willing to listen and understand our needs and design a specific sail that will work for our boat and our cruising plans. They are making us a symmetric spinnaker with a fairly wide and deep cut in the top section of the sail which will allow it to lift and fly out in front of our mainsail. We sized the spinnaker to be 30% smaller than our sail plan specifies with a heavier 1.5oz fabric that will handle 25+ knots of breeze. This should give us a strong sail that will hold it’s shape well and be fairly easy to control and douse with a spinnaker sock.
It’s also worth mentioning that there is another symmetric sail that is becoming more common, and that’s the Parasailor. It’s essentially a symmetric spinnaker with a parafoil wing in the center. The wing provides some lift and also can spill the power from gusts. It’s a great idea, but we decided against this sail for two reasons: It’s more difficult to get the sock down over the parafoil wing in stronger winds; and we know of another 5X that tried the sail and found it didn’t work very well. The 5X has a lot of acceleration and it tended to collapse the sail too much when they sped up on waves (although it seems that could be solved by experimenting with the size of the sail).
We don’t have the all the deck fittings and control lines needed to fly a symmetric spinnaker on Wildling, so now that the sail is ordered, the next project is to prepare the boat to be able to use it.
On May 23rd, Outremer had arranged a crane to lift a new 5X into the water, so we were able to take advantage of that to lift Wildling out so we could check to see if the saildrives were damaged when we changed over to the EWOL propellers.
The smaller diameter, replacement EWOL propellers weren’t ready in time for the crane lift, but we decided to lift out anyway because I needed to know if the engines were damaged, and the only alternative was to take the boat over to Canet-en-Roussillon which is a 3 day round trip journey, and a major hassle.
The lift out was very easy, the guys have done this many times, and you can tell. They have it down to a well organized process. The Volvo engineers came and removed the EWOL propellers, then inspected the drives and used some instruments to measure the shafts to make sure there were no problems with the bearings or the shaft geometry. Everything checked out fine, so they put the original 4 blade folding Volvo propellers back on.
As soon as we lifted out we noticed that there was a large misalignment between the two rudders. Since the boat was hauled out the previous month in Canet en Roussillon, the misalignment must have been present at that time, but nobody noticed? In any case, it’s another reminder that you should always be there in person when your boat is being worked on!
After correcting the alignment of the rudders, we put Wildling back into the water, and the following morning we took her out for a quick test drive to make sure the engines were OK. All the vibration and noise that we had with the EWOL propellers was gone, and our engines were back to their previous smooth and quiet operation. A huge relief, but also a disappointment that our EWOL propeller test didn’t work out as I had hoped.
I discussed next steps with Xavier at Outremer, and we decided to wait until the next scheduled haul out to try the new model EWOL propellers, so we will be using our Volvo props for the rest of this sailing season.
The following Sunday morning, Robin, Gavin, Lindsay and I left La Grande Motte, to sail over to Marseille. I had called the Port Cobières marina the Friday before to make sure they had our place ready, and they told me everything was fine. Turns out, not quite!
We left at sunrise (or at least at the the time of sunrise, because the weather was nasty) in a cold drizzle, with very little wind. The forecast called for 15 to 20 knots from the South West by mid morning, so we hoisted the main and jib, and motor sailed for about an hour until the wind picked up.
After an hour, the wind lifted to around 10 knots, and later built to the foretasted 18 to 22 knots, so we had a beautiful sail over to Marseille, sitting between 10 and 13 knots boat speed. The wind was coming from dead astern of our intended course, so we gybed back and forth the entire way, keeping the boat between 150 degrees and 160 degrees to the true wind. This is a nice point of sail for Wildling, with comfortable motion and decent speeds.
I really like coastal cruising like this when we’re tacking or gybing back and forth along the coast. The only tricky part is to not wait too long to come about when we’re on a course that will intersect the land. It’s deceptive how much ground you cover at over 10 knots and a couple of times, I cut it a bit close!
Robin and Lindsay were not feeling too great on the trip over, so they took some seasickness meds and had a sleep, so I was single handing the whole way. This is when I love the self tacking jib! Gybing the mainsail is easy also, so single handing is pretty simple on Wildling, and for me, it’s a great way to spend a day on the water.
We arrived in Port Corbières just after lunchtime, and went to our designated dock, but there was another boat already there, and no places free! Damn! We ended up tying up to a concrete pier near the public boat ramp just next door. Not very safe, but there were no other choices.
I called the emergency numbers for the port, and a guy came over and found a temporary place for us. Robin and I started over, but just as we were arriving at the new place, another catamaran came in ahead of us and took it! Damn! And then another catamaran came in behind us and took the place on the pier we had just left! So we were stuck, and had to hold position in the channel while we negotiated with the port after hours staff and the other boat to let us take their spot.
After about half and hour, the interloper agreed to move to another spot. He was smaller than us, so he had more options of where to park, so we could finally go in and tie up at the dock. We were positioned at the dock in between two rows of boats, which meant we were blocking 4 other boats from leaving their slips, so not an ideal situation, but OK for the night, and we were told the guy who manages the port would sort it out in the morning.
The next day we met the port manager and he assured us he would find us a place that afternoon. He said the same thing the next day, and the next, and the day after that, but finally he moved the boat out of the place he had assigned us, and we were able to move Wildling into her new home on Saturday morning!
It seems the sense of urgency we are used to doesn’t really exist here. People are pretty laid back, which mostly is a really good thing, but Robin and I were getting pretty anxious by the end of the week, so we’re happy to finally have Wildling tied up in a safe place.
We have been working out a plan with the Outremer engineering team to sort out our propeller problems. We have decided to lift Wildling out of the water by crane on Monday next week and will have Volvo engineers check the saildrives to see if there has been any damage from the malfunctioning EWOL propellers. EWOL is still making a replacement set of propellers that will not be ready in time for the crane service, so if the saildrives are OK, we will remove the EWOL propellers and put the original Volvo folding propellers back on. Based on what we find during this process I will decide if we will do another test with the new EWOL propellers, but this will have to be after we move Wildling over to Port Cobières in Marseille.
I’ll take video and photos of the replacement process and will post as soon as I can next week.
Matthieu has posted a bunch of photos from the Outremer Cup regatta on the Outremer Yachting Facebook page. Here are some of Wildling in action:
We raced Wildling in the Outremer Cup regatta last weekend, and while we were careful about our sails and rig loads and didn’t break anything, we did push the boat a bit, and there was one point when we decided we should furl the Code-D because it was getting overpowered, and right when we were furling, the gennaker on the boat next to us literally exploded in a wind gust, creating a vertical tear from head to tack!
It was a scary reminder of the need to pay careful attention to rig loads on a catamaran, and it got me thinking, how much is too much, and how do you know when you’re pushing too hard?
When I learned to sail on monohulls, we were taught the two golden rules for managing an overpowered boat.
Rule #1: When the boat heels too much, depower. Usually first by letting the traveller down and then by reefing. Since Rule #1 varies based on experience and sea state, i.e. 20 degrees of heel feels OK to me, but is too much for Robin, we have golden Rule #2.
Rule #2: It’s time to take a reef when you first think about it. Or in our case, it’s time to take a reef when Robin tells me to stop leaning us over so far, damnit! Gusty conditions on a monohull are not a big deal either, just reef to give a comfortable heel most of the time, and let the boat heel further every now and then to spill the power from the gusts.
So how do we apply these two golden rules to a catamaran? It turns out, not very easily. It becomes less of a feel thing, (at least until you get to know your boat) and more of a numbers game. Catamarans don’t heel, so they can’t spill the power of the wind, all the power has to be absorbed by the rig. In gusty conditions, this becomes dangerous, as rig loads can become unsafe very quickly, so the golden rule for catamaran reefing is to reef for the gusts. But since the gusts are occasional, how do we know when and how much to reef, and what happens if we carry too much sail? We’re not going to capsize in 25 knots of wind, so no big deal right? Since stories of rig failure, broken masts and exploding blocks seem more common on catamarans than monohulls, I think it might be a bigger deal than I realized.
Our catamaran came with a reefing plan from Outremer. The plan tells us at what wind speeds we need to reef, or change headsails to avoid overloading the rig or capsizing. Here’s the reefing plan for Wildling:
We were above this plan at times during the Outremer Cup, and nothing broke, we even flew our Code-D in 20 knots, so we have proven that Wildling can handle more load than this plan dictates, so is the plan just a conservative suggestion from the manufacturer, designed to make sure no boat ever gets damaged, or is it a prime directive to be broken only at great risk? After our racing experience, the answer wasn’t as clear to me, so I did some calculations to try and find out.
Before I go into the calculations, I want to give a plug to the Attainable Adventure Cruising website. John, the author, has published a large amount of excellent information on offshore cruising and I have learned a lot from him. I was reading his article on rigging a “proper” jibe preventer (because after our autopilot went crazy last year and jibed us without warning, I need to rig a system to protect the boom when it happens again). In the article he talks about mainsheet loading at different wind velocities and how to calculate the forces the preventer needs to be able to withstand. I started calculating the loads on our mainsheet using the Harken formula in John’s article, and the results were pretty interesting, so I ended up building a spreadsheet to determine Widling’s mainsheet loads at different wind velocities and different reefing points.
Here are my calculation results:
What’s impressive to see in these results is how much the rig load increases from a gust. For example, with a full main at 20 knots, a gust of just 10 knots higher, more than doubles the rig load! My calculations are probably not that accurate, so the actual numbers are not very useful, but what is interesting is to see the relative changes in load as wind increases, and as we add or remove reefs.
I wondered how much load we were putting on our boat when we exceeded the reefing plan. The hardest we have ever pushed Wildling was during our delivery test sail, when we had full main and jib in 30 knots on a beam reach in flat water. Our boat speed was 19.7 knots! Sailing at these conditions gives a calculated load of about 3,750kg, which is about 10% higher than the maximum load in the reefing plan at 3 reefs and 50 knots. So I’m going to use this as the maximum safe limit for our boat.
If we plot the loads on a chart, and define a safe zone below the Outremer reefing plan, and a danger zone above our maximum load, and then put a racing zone in between, it looks like this:
This chart helps to put everything into context. The Outremer reefing plan might look conservative in steady conditions, but it becomes much more realistic when you take into account the loads from gusts. For example, with no reefs at 25 knots steady, we’re under the danger zone, but we now have only a 5 knot gust margin. That might be OK in a race when you’re watching things very carefully, but for cruising, it’s just not enough. Taking Outremer’s advice and reefing at 20 knots, gives us the margin we need to handle changing conditions.
So what are the conclusions from all this? For me there are two important conclusions:
- BEWARE OF GUSTS! – The rig loads they generate are extreme and they happen very quickly. Reef early when sailing in gusty or building conditions. Reef deeper if sailing around squalls.
- Follow the plan! – This exercise has given me greater respect for the Outremer 5X reefing plan. It is well designed and has a good balance between performance and realistic gust tolerance
We know from experience that we have a strong boat that can go beyond the reefing plan, and that’s great because it gives us a safety margin, but it’s important not to confuse occasional race conditions with long distance offshore cruising conditions, and the need to sail conservatively. The nice thing about a performance cruising catamaran, is that you don’t have to push it in order to sail fast and be safe.
Day 3 of the Outremer cup was a mixed affair for us, we did really well with our sail handling and maneuvers, and didn’t make any mistakes on the racecourse, but our propeller issues took us completely out of contention for any prizes, which is a real disappointment.
The weather was a lot nicer, sunny, warmer, and winds between 15 and 20 knots, we were sailing with full main and jib, and used the Code-D gennaker on each of our downwind legs. Lindsay and Gavin came along today and we had our same crew from yesterday (François, Bobby, Kent and Belinda), plus Riley and Elayna from Australia, and François’ girlfriend Sara also joined us. Having extra experienced people really helped, and we pulled off all our sail changes, tacks and jibes perfectly! Bravo team Wildling!!!
All in all we had a very nice day on the water, but this propeller issue is really bothering me. What we’re finding with the EWOL propellers that we had installed, is that they are not feathering correctly when the engines are turned off. They are supposed to feather to a flat position that offers very little drag, but this isn’t happening. We had to try several times on each engine to get them to feather at all, and even when they did, they were still spinning under sail. You can feel the vibration of the gears turning slowly in the engine rooms, and there’s a rotating stream of bubbles in the wake of the boat that clearly show the propellers are dragging. The result is like driving a car with the handbrake half on, and it cost us a lot of boat speed.
It’s disappointing, as I know a lot of people are using EWOL propellers and they are working very well, but they are certainly not working on our boat. I’m going to switch back the the Volvos and ask Outremer to fully test to see why the boat speed under motors is so slow with the Volvos. I’m also afraid that the saildrives have been damaged by the EWOL propellers, the grinding and vibration noises that we get when running the EWOL props are pretty alarming! Hopefully it’s a water turbulence noise, and not a gearbox mechanical noise, but in any case I’m sure Outremer can find out where things stand and get my 5X back to her former speedy self!
Here are some photos Robin took of our day…
OMG, sailboat racing is mayhem! Today was my first experience racing a sailboat, and it was pretty crazy! We went out after the briefing to do a timed run and two group races. It was windy, 20-30 knots, and cold! So being a cruiser and not a racer, I wanted to reef the main and sail with just our self tacking jib for a headsail. The timed run was pretty cool, well that is, it was cool until I got too close to a crab pot flag and snagged the pot line with our daggerboard, and we ended up dragging the damn pot for half a mile before we agreed it wasn’t coming off on it’s own, and we had better stop the boat and disengage it. We continued on minus our crab pot, but our timed run was a disaster.
Then the group racing began, this was pretty stressful for me, because there are so many boats going in all directions and coming so close you could reach over and touch them. I nearly had about a dozen heart attacks as we had multiple close encounters! Lucky for me, I had François Tregouet from Outremer with us, so he coached me through the boat dodging process!
We were doing pretty well in the first race, and the wind had dropped below 25 knots, so we got cocky and thought we would unfurl our Code-D gennaker on the downwind leg. The Code-D worked so well that we immediately accelerated to 17 knots boat speed and nearly ran over the boats in front of us, which required more boat dodging coaching from François! And because we went so fast, we ran out of room and started furling our Code-D too late, and then the furling line got caught up, so we had to continue our downwind leg for an extra mile while we got the Code-D in before we could get back on course and continue the race, so obviously our first race didn’t go as well as we had hoped.
On the final race of the day, we were waiting for the start, and it wasn’t until all the boats began charging for the start line, that we realized we had turned our radio down and missed the starting call. Oops! So we crossed the line dead last, but François had us turn opposite tack on the beat to the windward mark, and we caught up to most of the boats as we rounded the mark. We skipped the Code-D this time and stayed with our reefed main, and jib which wasn’t super fast but at least kept us in the hunt and we crossed the finish line not too far behind the lead group.
So, after a few stiff drinks, and some time to calm down a bit, I would say that while racing is not really my thing, I did learn a lot, and I was really impressed with the other boats and crews out on the water today, these guys know their stuff. Let’s see if we can do a bit better tomorrow!
Here are some photos that Robin took today…
The annual Outremer owners regatta began today in La Grande Motte France, with a friendly prologue event where all the boats went out together for a social sail. We all took along passengers that mostly consisted of people that work at Outremer and their families. We owe these folks a lot for all the care and skill they put into building our boats, and it was a pleasure to be able to go sailing with them!
The weather was beautiful, sunny and warm with about 10 knots of wind. Here are a few photos…
It’s been a while since I posted, and mainly because we have been busy with work and getting our family established in Aix-en-Provence (near Marseille). Things are going well on both fronts, but it has been a bit crazy.
We spent some time at the Multihull boatshow in La Grande Motte, which was good, but I found out later that I missed out on seeing this amazing catamaran!!!! If we ever feel like Wildling is too small or too slow, I’m going to try and convince Robin we need one of these!
Outremer had quite a few boats on display at the show, including the new 4X, which is a performance version of the Outremer 45. They added carbon and changed the ratio of solid layup to foam sandwich in the hulls to remove weight, increased the power of the headsails and extended the transoms to increase waterline length. The 4X is now 47 feet long, faster than the 45 but still as seaworthy.
Also at the show was a new foredeck canopy manufactured by Delta-Voiles and on display on one of the new 5X boats. Great idea, especially at anchor in the tropics, we’re going to order one of these for Wildling.
In between boatshows and starting new schools for the kids, we caught up with our friends in Marseille, who as usual blew us away with their seemingly endless supply of excellent wine, we loved this one!
We’ve had some issues with our B&G instruments lately, I’m starting to worry a bit about our decision to go with B&G, as I’m not sure the reliability of the new H5000 equipment is as good as the older Hydra systems we had on our last boat, that were rock solid the entire time we owned it.
In the last three weeks, we had to replace the masthead sensor unit because we lost our wind direction information. Then we had a problem with the main chartplotter not retaining the configuration for the boat speed sensor, so we had no boat speed information. It seems this was an issue that occurred when the system software was updated. And this week, the sea water temperature went haywire, so we are going to have to replace the water temperature sensor. I hope we can get these systems stabilized soon!
The biggest headache we have had to deal with since arriving in France was to find a marina berth for Wildling closer to where we are living. I called nearly every marina between Marseille and Nice and nobody had any room for us. We owe a huge thanks to François from Outremer for recommending we try Port Corbières just west of Marseille, I called them and they found us a place, so we are all set! We visited the Port today and it’s a really nice and very well equipped marina, and it’s only 25 minutes drive from where we are living in Aix-en-Provence. Marseille is also a great base to keep the boat. There are lost of good cruising locations nearby and it’s a good departure point for Corsica and Sardinia, which is where we are planning on cruising this summer.
I also talked with Sergio from EWOL today about our new, smaller diameter propellers. They are going to be ready in about two more weeks, so we will probably install them after we move Wildling over to the new marina, sometime after the Outremer Cup which is taking place next week in La Grande Motte.
The big project that we have been planning over the winter is replacing the Volvo folding propellers with EWOL feathering props. I’ve been anxious to see if we could get better motoring performance, not because I plan on doing a lot of motoring, but rather because the speed under engines seemed very slow to me, 5-6 knots at 2,000 rpm, and I was worried there might be something wrong.
The new propellers were fitted during the haul out at Canet, so Stéphane was able to try them during the run back to La Grande Motte on Monday. Unfortunately it didn’t go so well. The engine rpm was limited to 2,000 and there was a lot of vibration that increased with the rpm.
The limited engine speed could be corrected by reducing the pitch of the props, but the vibration was a bigger concern. We were fortunate that Sergio from EWOL is in La Grande Motte this week for the International Multihull Boatshow, so he joined us onboard Wildling to supervise the testing. Let me say how impressed we have been with EWOL, they truly stand behind their propellers, and have been very involved in helping us find the best propeller solution for the Outremer 5X.
We had a scuba diver go under the boat to change the propeller pitch, which is a very simple procedure on the EWOLs, and then we took the boat out for some test runs at different engine revs and wind directions. The reduced pitch allowed us get the revs up to the design max range, but the vibration was still present. The consensus of the team is that the diameter of the propellers is too large, which is leaving too little space between the blade edges and the hull surface. This causes cavitation and turbulence, and that causes the vibration. A smaller diameter prop with the correct pitch “should” eliminate the vibration while still keeping the performance.
That’s the bad news. The good news is the performance is much better with the EWOL props. Instead of 5-6 knots at 2000 rpm we were getting around 8 knots, and over 11 knots at full speed. EWOL is making us some smaller props now, and we will fit them and retest in a few weeks time.
Although it would be nice to have everything perfect the first try, it usually takes some trial and error to get the right propeller match for a new boat, so this is to be expected. One of the main reasons I selected EWOL for this project was because they were willing to work with Outremer to find the right solution, and they have certainly been true to their word on that count!
Other than the propellers, Wildling is pretty much all ready for the sailing season. After her delivery back from Canet-En-Roussillion, we went over everything with Stéphane. The wind angle sensor stopped working during the trip back from Canet so we replaced it. It was a bit intermittent last July during our first voyage, but then worked fine since, so the gremlins that caused the original problem must have returned.