It will be intersting to see what the mobo designers make of this

[DAKA]

That ugly bow as just won a race with a 150 mile lead over its traditional rivals.

I can imagine on the plane this bow will give a smoother ride in a head chop and greatly reduce drag increasing fuel economy.

Any mobo builder could get an extra cabin in the bow so its not just the fuel economy but also value for berthing fees, but I expect only sealine have the guts to build this bow into their designs.

 

[mersey]

Nothing new in that..

Humber Keels have had that bow shape for years, available in both sail and power variants.

 

[powerskipper]

ooo

That ugly bow as just won a race with a 150 mile lead over its traditional rivals.

I can imagine on the plane this bow will give a smoother ride in a head chop and greatly reduce drag increasing fuel economy.

Any mobo builder could get an extra cabin in the bow so its not just the fuel economy but also value for berthing fees, but I expect only sealine have the guts to build this bow into their designs.

Interesting design, I wonder how she would handle in a marina. and if on a power boat, what sort of speeds she could get.

 

[rbcoomer]

Hrmm. I think Powerskipper hit the nail on the head there - speed! After all, those sailing dudes aren't usually in much of a hurry are they? They also don't go fast enough to worry as much about handling and I'd suspect it would have more tendency to try going over waves than through them. Not a problem at 10kts, but what about at 30?

I think those of us not looking to leave a trail of burnt £50 notes in our wake would also think carefully about a 'blunted' pointy end...

 

[Nick_H]

[I can imagine on the plane this bow will give a smoother ride in a head chop

Really? I think it would be like crossing speed bumps in a shopping trolley

 

[DAKA]

when a mobo gets on the plane the front is well out the water, there will be 4 ft waves that catch the bow but rounded should slap less than two flat sides (just thinking, I accept i could be wrong but the principal worked well for the above sailing boat. although a sailing boat it is designed to plane.

example photo of a mobo on the plane showing the sharpe bit above the water, the boat will only crash through the tops of the large waves, a rounded hull perhaps will not slap the same thus reducing the wave braking effect.

 

[wakeup]

Umm I think you have it arse about face. The fine sections of the bow 'cut' through an oncoming wave to reduce or eliminate any slapping. A flatter surface will result in the hull slamming and slapping for sure. Have you ever been out sailing in an AWB when it is going up and down over large waves either with the wind behind or on the nose? Well I can tell you they slamm. I'd rather be in a boat with a fine bow than not.

 

[DAKA]

Im not arguing , just thinking out loud but remember this is a radical design which is proven to work.


We all know we prefer not to hit a wave head on.
when it gets rough we taken them at 45' given a choice.
Now looking at the mobo bow above and thinking about a 45' wave hitting the bow, it is a huge flat area to slap with a braking effect.

now look at the ugly bow thinking about a 45' wave, much smoother dispersion of the wave.

 

[wakeup]

Im not arguing , just thinking out loud but remember this is a radical design which is proven to work.


We all know we prefer not to hit a wave head on.
when it gets rough we taken them at 45' given a choice.
Now looking at the mobo bow above and thinking about a 45' wave hitting the bow, it is a huge flat area to slap with a braking effect.

now look at the ugly bow thinking about a 45' wave, much smoother dispersion of the wave.

The only design rationale I can think of for this bow design is for close quarters single handed racing so mixing it up between yachts going round bouys is less likely to causes an incident bit like a bumber car effect with no sharp pointy bits to tangle and clatter together.

It looks like a modern mirror dinghy on steroids.

 

[flaming]

Im not arguing , just thinking out loud but remember this is a radical design which is proven to work.


We all know we prefer not to hit a wave head on.
when it gets rough we taken them at 45' given a choice.
Now looking at the mobo bow above and thinking about a 45' wave hitting the bow, it is a huge flat area to slap with a braking effect.

now look at the ugly bow thinking about a 45' wave, much smoother dispersion of the wave.

The thing you're forgetting about the mini is that the shape is designed to work with the boat heeled, as when heeled the wetted surface area is significantly reduced, but the "power" of the hull (essentially the resistance to heeling - meaning more sail can be flown) is much higher as the wetted surface is now further to the leward side than with a conventional design. Basically it's trying to get a mono to behave more like a multi. And it was the reaching conditions - where being able to stand up to its sail was the most important factor - where that boat created its lead. In the downwind conditions, where the boat is much flatter it did not have the same advantage.

I haven't seen an awful lot of heeling motorboats recently....

 

[Keen_Ed]

The reason it worked was stability. By building the wide bow, he maximised form stability, and therefore the ability to resist the heeling moment developed by the sails. The shape really came into its own in the second half of the second leg of the race - when the fleet were sailing in the trades to Brazil. IIRC, he said that he's as stable with his keel centred as other boats are with their keels fully canted. So when he cants his keel, he's can use a lot more power.

After 2 (?) years with the boat, he's also now got to the stage where he's not too disadvantaged in the areas where the shape is slow - light winds , where lots of wetted surface is a hindrance, and his competitors aren't having to depower. But he did come second in the first leg of the race - which was mainly a very light wind affair.

The question remains as to whether this shape will work at other sizes. Minis are only 22' long, so I can see them sailing up and down waves when at sea. A longer boat might plough into them, as the ratio between LOA and wavelength is higher. It's not a shape that would look to good in a Solent chop.

Given the greater reliance of sailingboats than motor boats on form stability, I doubt there's much crossover.

 

[DAKA]

Thanks for the extra details Ed and Flaming , I would have liked to have test driven it with a 100hp outboard but I dont suppose they will be very enthusiastic



I accept everyones argument, it would make a **** mobo.