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MR.CLEAN

va or nova? murnikov's latest mx...

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Brian Hancock tells us the offshore SpeedDream is on hold for the moment. In the meantime, here's a look at something entirely different from outside-the-box designer Vlad Murnikov - the mxNova. From Brian:

SpeedDream is about innovation. It’s our touchstone yet it doesn’t have to be as radical as a Flying Keel or a wave piercing bow and stepped hull. In fact, we have been working for a while on a classic racing keel boat, something that nobody has taken a fresh look at for a very, very long time. We are calling the project mxNova.

The iconic Star is well over 100 years old, and the Dragon is not much younger. More recent designs, the Etchell and Soling, are closing in on a half century since they were introduced. All of them have provided decades of glorious competition and spawned some of the world’s best and best known sailors; guys like Dennis Conner, Russell Coutts, and Lowell North, to name just a few. In no way do we think that mxNova is going to take away any of the illustrious accomplishments of these classes, but we do think that it’s time to take a new look at keel boats and bring in some fresh ideas.

Most recent keelboat designs are more ballasted dinghy than they are classic keelboat, intended to sail flat and relying on the crew for righting moment. We became curious as to whether there was room in sailing for a truly modern keel boat, a boat that is long, gracious and narrow and intended to sailed heeled with the ballast keel providing the power rather than bodies dangling over a lifeline. The result is the mxNova prototype.

Naturally, the boat features SpeedDream’s signature wave-piercing bow which gives way to a pleasantly narrow hull. There is nothing extraordinary about the design other than it’s thoroughly modern, even slightly futuristic. There is ample sail area with a square top mainsail that can be easily twisted off to depower in the puffs. The rig is simple and does not require complicated running backstays. All in all you have a powerful boat that is easily driven, which is in itself is not revolutionary, but that’s until you look below the waterline.

MxNova does not have SpeedDream’s Flying Keel; instead she has a keel that can make the boat fly - or at least, change its displacement substantially.

Attached to the bulb of a normal looking fin keel are two transverse wings. On the trailing edge of each wing are adjustable flaps similar to a trim tab sometimes found on the aft end of a keel or rudder. Their purpose is to turn a symmetric foil into an asymmetric one, thereby creating either downforce or lift when the boat sails upwind or downwind respectfully.

In the upwind configuration, the flaps are up, which creates a downwind force. This force 'sinks' the boat, providing 'virtual displacement', more stability and, by extension, more sail carrying capability. The opposite is needed when sailing downwind. With a control similar to one found on the Moth dinghy you adjust the angle of the keel flap to make it point down. The effect provides lift which in turn reduces displacement just when you need it. This minimizes drag and increases the boat’s ability to plane. This simple mxNova feature brings the classic keel boat into the 21st century and provides a great tool for competitive sailors to maximize its performance.

That’s the theory, but to make it work would require a lot of work – and money - and before committing to developing the new design we would like to hear back from the sailors of all stripes whether it’s worth it or not. The attached renderings are here to inspire conversation. What do you think?

Nova-A.jpg

Nova Concept-2.jpg

Nova Concept-1.jpg

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Brian Hancock tells us the offshore SpeedDream is on hold until life sorts itself out for their supporters and sponsor in Ukraine. In the meantime, here's a look at something entirely different from outside-the-box designer Vlad Murnikov - the mxNova. From Brian:

 

SpeedDream is about innovation. It’s our touchstone yet it doesn’t have to be as radical as a Flying Keel or a wave piercing bow and stepped hull. In fact, we have been working for a while on a classic racing keel boat, something that nobody has taken a fresh look at for a very, very long time. We are calling the project mxNova.

The iconic Star is well over 100 years old, and the Dragon is not much younger. More recent designs, the Etchell and Soling, are closing in on a half century since they were introduced. All of them have provided decades of glorious competition and spawned some of the world’s best and best known sailors; guys like Dennis Conner, Russell Coutts, and Lowell North, to name just a few. In no way do we think that mxNova is going to take away any of the illustrious accomplishments of these classes, but we do think that it’s time to take a new look at keel boats and bring in some fresh ideas.

Most recent keelboat designs are more ballasted dinghy than they are classic keelboat, intended to sail flat and relying on the crew for righting moment. We became curious as to whether there was room in sailing for a truly modern keel boat, a boat that is long, gracious and narrow and intended to sailed heeled with the ballast keel providing the power rather than bodies dangling over a lifeline. The result is the mxNova prototype.

Naturally, the boat features SpeedDream’s signature wave-piercing bow which gives way to a pleasantly narrow hull. There is nothing extraordinary about the design other than it’s thoroughly modern, even slightly futuristic. There is ample sail area with a square top mainsail that can be easily twisted off to depower in the puffs. The rig is simple and does not require complicated running backstays. All in all you have a powerful boat that is easily driven, which is in itself is not revolutionary, but that’s until you look below the waterline.

MxNova does not have SpeedDream’s Flying Keel; instead she has a keel that can make the boat fly - or at least, change its displacement substantially.

Attached to the bulb of a normal looking fin keel are two transverse wings. On the trailing edge of each wing are adjustable flaps similar to a trim tab sometimes found on the aft end of a keel or rudder. Their purpose is to turn a symmetric foil into an asymmetric one, thereby creating either downforce or lift when the boat sails upwind or downwind respectfully.

In the upwind configuration, the flaps are up, which creates a downwind force. This force 'sinks' the boat, providing 'virtual displacement', more stability and, by extension, more sail carrying capability. The opposite is needed when sailing downwind. With a control similar to one found on the Moth dinghy you adjust the angle of the keel flap to make it point down. The effect provides lift which in turn reduces displacement just when you need it. This minimizes drag and increases the boat’s ability to plane. This simple mxNova feature brings the classic keel boat into the 21st century and provides a great tool for competitive sailors to maximize its performance.

That’s the theory, but to make it work would require a lot of work – and money - and before committing to developing the new design we would like to hear back from the sailors of all stripes whether it’s worth it or not. The attached renderings are here to inspire conversation. What do you think?

I see nothing classic about this latest wet russian dream - EXCEPT _ it could look like a classic boat - flipped over and a hole cut out of the bottom to provide a cockpit

 

Vlad has some good ideas and is certainly not afraid to put it out there - now the challenge is to take it from wild concepts and into mature commercially viable boats - a much harder part of the process.

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Have you seen a Moth inverting the foils to "sink" for better stability?

That was my first thought as well. I'll have to think about this some before forming an opinion.

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''That’s the theory, but to make it work would require a lot of work – and money - and before committing to developing the new design we would like to hear back from the sailors of all stripes whether it’s worth it or not. The attached renderings are here to inspire conversation. What do you think?''

 

........I like the (almost) crowd-funder approach to yacht design,,,and the Rad ideas......where do I send my $10??

 

...it would only seem natural for these folks to team-up with DL,,,,a match made in heaven!

 

 

........all said 'n done,,,,,,a modern keelboat with an upsy/downsy control seems like a 'natural' but who's left to sail 'em??......everyone's on foiling cats now :mellow:

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Have you seen a Moth inverting the foils to "sink" for better stability?

That was my first thought as well. I'll have to think about this some before forming an opinion.

Unlike a moth, this design's hull will be in the water on the upwind legs, so not sure that's the way to think about it.

 

What I see as strange is unlike the keel bulb which is using gravity to create stability, the added flap control will be pulling this thing down at whatever angle it's heeled to. I don't know if that's fast or not, but it will be interesting to see.

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Probably never leave the drawing board, but if it did, likely to join the abandoned MXRay on trash piles behind yacht clubs.

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What I see as strange is unlike the keel bulb which is using gravity to create stability, the added flap control will be pulling this thing down at whatever angle it's heeled to. I don't know if that's fast or not, but it will be interesting to see.

.

....ummm,not a bad thing since when heeled,the keel 'usually' is to windward,,,so the downsy-flaps would be pulling both down and windward ;)

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Wouldn't it make more sense on an upwind course to use the flaps to torque the keel, i.e. generate downforce on the windward side and lift on the leeward side to improve righting moment instead of just increasing the overall drag of the hull?

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Probably never leave the drawing board, but if it did, likely to join the abandoned MXRay on trash piles behind yacht clubs.

.

......I actually think this is Muri's effort to take a chill-pill,,,make something which is a proper advance without being too radical.

 

...at a time when the design-world's gone crazy over foiling multi's----ironic

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All of which might be worthy of further consideration if not for the steaming pile that is the MXRay. What a heavy, poorly executed slug that thing is. Sorry, when you put real garbage into the marketplace, you get judged by it.

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What I see as strange is unlike the keel bulb which is using gravity to create stability, the added flap control will be pulling this thing down at whatever angle it's heeled to. I don't know if that's fast or not, but it will be interesting to see.

.

....ummm,not a bad thing since when heeled,the keel 'usually' is to windward,,,so the downsy-flaps would be pulling both down and windward ;)

I got that, but I'm questioning what's happening while those "great things" are happening. Have any other wing keeled boats played with this before?

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All of which might be worthy of further consideration if not for the steaming pile that is the MXRay. What a heavy, poorly executed slug that thing is. Sorry, when you put real garbage into the marketplace, you get judged by it.

.

...yeh,,the MX build quality was rather lacking,,,but it gets some creds for being the first purpose-built singlehander with chute to hit these parts at least :mellow:

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What I see as strange is unlike the keel bulb which is using gravity to create stability, the added flap control will be pulling this thing down at whatever angle it's heeled to. I don't know if that's fast or not, but it will be interesting to see.

.

....ummm,not a bad thing since when heeled,the keel 'usually' is to windward,,,so the downsy-flaps would be pulling both down and windward ;)

I got that, but I'm questioning what's happening while those "great things" are happening. Have any other wing keeled boats played with this before?

.

....oh I'm sure there's been boats doing this already,,,,about as long as there's been wing keels.

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All of which might be worthy of further consideration if not for the steaming pile that is the MXRay. What a heavy, poorly executed slug that thing is. Sorry, when you put real garbage into the marketplace, you get judged by it.

.

...yeh,,the MX build quality was rather lacking,,,but it gets some creds for being the first purpose-built singlehander with chute to hit these parts at least :mellow:

 

 

But, have you actually sailed one ? I'd take a retro-fitted something else any day of the week. Anybody that was unfortunately enough to have gambled on one of these versus something cool, like a Farr3.7 or IC, any windsurfer or a byte just got the shaft - in the name of misguided 'innovation' - but the fact remains, that thing just isn't fast, trustworthy, or very good. at all.

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All of which might be worthy of further consideration if not for the steaming pile that is the MXRay. What a heavy, poorly executed slug that thing is. Sorry, when you put real garbage into the marketplace, you get judged by it.

.

...yeh,,the MX build quality was rather lacking,,,but it gets some creds for being the first purpose-built singlehander with chute to hit these parts at least :mellow:

 

But, have you actually sailed one ? I'd take a retro-fitted something else any day of the week. Anybody that was unfortunately enough to have gambled on one of these versus something cool, like a Farr3.7 or IC, any windsurfer or a byte just got the shaft - in the name of misguided 'innovation' - but the fact remains, that thing just isn't fast, trustworthy, or very good. at all.

.

....haha...I said 'first' not best!!

 

...sailed a dealer demo when they were new--couldn't keep with lasers upwind,,but downwind was fun until both the blades sheared :mellow:

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Dear Mr Vlad,

 

Please contact me for details of where to forward royalties...

 

Stuffing around back in 2006. Actually, could be interesting, I did post that on one of the Mini forums somewhere..

post-9315-0-37923700-1404762758_thumb.jpg

post-9315-0-89284500-1404762846_thumb.jpg

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given the fact that metre classes have limited the amount of moveable appendages underwater, i think it has been done before.

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All of which might be worthy of further consideration if not for the steaming pile that is the MXRay. What a heavy, poorly executed slug that thing is. Sorry, when you put real garbage into the marketplace, you get judged by it.

.

...yeh,,the MX build quality was rather lacking,,,but it gets some creds for being the first purpose-built singlehander with chute to hit these parts at least :mellow:

 

But, have you actually sailed one ? I'd take a retro-fitted something else any day of the week. Anybody that was unfortunately enough to have gambled on one of these versus something cool, like a Farr3.7 or IC, any windsurfer or a byte just got the shaft - in the name of misguided 'innovation' - but the fact remains, that thing just isn't fast, trustworthy, or very good. at all.

.

....haha...I said 'first' not best!!

 

...sailed a dealer demo when they were new--couldn't keep with lasers upwind,,but downwind was fun until both the blades sheared :mellow:

 

I passed one upwind with my Sunfish....................

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rather than having the flaps "sink" the boat to make the boat think it has more displacement. think about about ailerons on an aircraft. when the ailerons on the wing work opposite of each other. the plane rolls

rc-airplane-ailerons.gif

If we did the same thing on this winged keel... as the boat heels (rolls) over. use the ailerons on the wing of the keel to counteract the heel. So as the boat heels to the leeward youd want the windward wing to dig in and pull down and the leeward to create lift. the question then is a matter of physics and a "lever" could enough force down at the keel create enough roll to counteract the heel... but not enough drag to really slow the boat...

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Was Speeddream a breakthrough? Didn't really take off, did it? Sinking the boat to go upwind faster, can't wrap my mind around that one. Assuming you did build it, how long would these movable foils stay movable in salt water? Grab another napkin and keep doodling.

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rather than having the flaps "sink" the boat to make the boat think it has more displacement. think about about ailerons on an aircraft. when the ailerons on the wing work opposite of each other. the plane rolls

rc-airplane-ailerons.gif

If we did the same thing on this winged keel... as the boat heels (rolls) over. use the ailerons on the wing of the keel to counteract the heel. So as the boat heels to the leeward youd want the windward wing to dig in and pull down and the leeward to create lift. the question then is a matter of physics and a "lever" could enough force down at the keel create enough roll to counteract the heel... but not enough drag to really slow the boat...

 

I would say no. difference between planes and boats is the whole double medium thing. When you introduce additional drag in the H20 side, you need a huge amount of increase in positive lift in the air side just to stay even, let alone increase overall speed.

 

I just don't see it with the whole rolling/lifting/sinking keel concepts generating additional lift over drag, or additional speed.

 

As we saw with the AC72's the big jumps in speed involved minimizing water drag, not increasing air horsepower. they got rid of the genny's fir christ sake...

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How does this crap make it on the interweb? There are plenty of smart people making interesting boats that will actually work. Scooter tries to promote the most hopeless, and ill conceived projects, while ignoring some real innovation that other, dare i say, more intelligently edited sites are all over. Seems like money, and wingnuts are getting on the front page, while innovation and real sailing is often left off.

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The MX Next was promoted as cruising at 30 kts. No actual performance data has ever been released to validate that fact but based on the videos put out it doesn't seem to get over about half that speed. Now, rather than demonstrate performance of a product up to its specification this mob seem to be trying to sell something different. What gives?

 

Where is there a race result or even a comparative speed test showing that Vlad's boats are as fast as he claims? I don't see any.

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Whenever you induce lift on a foil you also induce drag proportionally, don't you? The flaps are built to produce lift way beyond the usual lift of a keel, so they would also produce drag that is much bigger. Wouldn't this obliterate any advantage on the displacement? I'm not an engineer, this is just from what I remember from my flying classes some 30 years ago.

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I think that this keel will work upwind.

 

When trimmed to produce downforce, and heeled to leeward, it will both act to counter heeling and produce some sideforce to counter leeward force from the sail. The more the boat heels, the more sideforce the wing will generate, allowing the boat to keep course without reducing sail. (Of course the bulb will then make more counter-heel force because it will have greater moment).

 

Also, the lift/drag of the keel can be tuned to the power of the wind, so in light winds you minimize drag because you don't need as much lift. In high winds, you max it out because there's plenty of power and you're at hull speed anyway.

 

Downwind, it's great too because it will push the nose up so the tail can plane

 

All in all, this is a better idea than a swing keel because it needs less power, can be made sturdier, and may be just as effective.

 

This is probably a smarter boat to build than Speed-Dream

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Looks like a sketch by someone who understands foils and vectors, but little knowledge of hydrodynamics and hull resistance. The downward flap thingy concept was already exploited in Australia II, although it didn't use a movable flap, but rather relied on the natural cross flow tendency at the keel tip. Not as dramatic an effect, but helped in reducing induced drag as well, whereas the keel flap thingy would likely generate huge amounts of drag. I could go on, but I'll stop here.

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The fly in the ointment is drag. Flaps rotated past a very small offset from center add drag which increases exponentially as the flap is moved. Is there sufficient benefit before the increased drag counters any increase in VMG?

 

In a moth or foiling platform that lifts the hull out of the water the increase in foil drag is far outweighed by a decrease in hull drag. In fact as the speed increases the flap requirement decreases.

 

The moth also heels to windward letting the lifting foil also lift the boat to windward. Would combining a "sinking" horizontal flap with a "lifting" flap on the vertical portion of the keel create enough windward lift to counter the cost of the drag?

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I think the flaps will work. Whether they work well enough to justify the added cost, complication, maintainence, and potential warranty issues, is another matter. IMO, probably not.

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This can't work efficiently. There's no rudder foil to adjust pitch so it must be controlled by the main foil and sail trim. Not fast. The more the boat heals, the less efficient the mail foil becomes since force generated by the foil is parallel to the keel, not gravity or buoyancy.

 

Counter-rotating "ailerons" are interesting and have been tried on Moths, they don't work (anyone using them at the Moth Worlds?). Their rotation effect is limited because the force is at 90° to what would be optimal to counter roll, and they're offset from the hull by the length of the keel. A vertical trim tab on the lower portion of the main strut would be very much more efficient at creating torque to counter heal (which is why aircraft ailerons are on the wing, not stuck up at 90° on the end of the wing).

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For foil assist downwind there is no question the keel foils would work and work well in reducing displacement. As to the effect of up flap on upwind legs I'm not so sure but it's sure worth a try and not that hard to find out for sure. I like the keel foils downwind.....

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Sorry, the downforce flap thing is a total fail.

 

As Paul Vestas why. He'll explain. It has to do with the other foil--the vertical one. The high pressure produced by the windward flap, pushing down, will destroy the low pressure on the back side of the vertical foil. The boat will generate leeway, much more friction drag than it should for the lift.

 

This idea has been tried unsuccessfully before. Wingnuts keep bringing it up. I don't know why.

 

What does work is a lifting foil to leeward. That is called a hydfoil. As in MONITOR. Or Mayfly. Or That French Thing that is Cool. Or pretty much nay hydrofoil with the exception of the moth, which does a clever inverse of a keelboat.

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Absolutely 100% false,fastyacht. The downforce is one of the reasons that this could work well-see the MPX sketch below and the other sketch that shows why it could develop substantial RM upwind with the right hull. Foilers like the Rave, Skat, Hobie Trifoiler, Osprey and others have used downforce developed by the windward foil to drastically increase RM on those boats. It works very well. And off the wind it could reduce displacement with vertical lift from the foils but it wouldn't have the downwind RM of DSS, but the foils would be well submerged. I think the idea has merit on the right hull.



 

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False? What I say is F A L S E ????

 

What the FUCK is your problem? You can disagree. But I didn't say anything *false*. Choose your words more wisely.

It's fucking stupid. Lots of trouble for little gain.

 

Putting pull-down foils way out to windward is completely different. Of course that can be effective. This is lots of trouble and it negates itself for the reasons I described. You are kidding yourself if you think stubby little foils in the vicinity of the actual lateral keel are going to help. You are going to destroy more lift than you are going to be able to use to go faster. You are also failing to notice that the "righting moment" generated by the phantom dsiplacement is also producing force the wrong way--counteracting the lateral fin. Near upright, no, very little but then you have very very little moment arm. And I haven't even gotten into the angle of attack aspects, the pitching aspects, lots of other shit I don't feel like going into.

 

Some of us thought about all this shit at age 12, and then finally disproved it at age 19 in school. This is reinventing a Bad Idea.

 

Vlad does some neat ideas. But this is not one of them. Doug you should build it, definitely.

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Sorry, the downforce flap thing is a total fail.=100% False! Sorry, I should have made this specific reference clearer-now I have.

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It isn't complicated to you because you're looking at it simplistically. I'm not trying to aggravate you or cause you to revert to your childhood-I'm trying to suggest that you think about this scientifically without the "shit" and "fuck" portion of your apparent stream of thought.

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Fuckin-a Doug, I do this shit for a living. I just don't feel like laying it all out. There are more important ideas to explore and designs to complete.

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I was going to read the whole thread, then I saw DL was here. Could someone explain whether it'd be wasting time to?

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