23 replies to this topic

[Se7en_speed]

So it looks like the new owner of Moonwave is eager to share some pre-launch pictures on the boat's new website! http://moonwave.com/?page_id=2

Here are some interesting shots




Is that a folding dagger board I see? The 66 had a retractable one. The props also look like they have been pushed much closer to the stern than they were on the 66. This was probably enabled by the electric drive and IMHO should help with maneuvering.




However it does look like the props are no longer mounted up and inboard of centerline, now they are on centerline and almost the deepest part of the draft. I wonder how this will affect beaching? Is that even a priority with these types of boats?


Here we can again see what I think are folding dagger boards, I wonder if they retract flush or if they are always that deep. Or maybe it's not a dagger board at all, can we get some clarification on this PJ?

[Oxygen Mask]

folding dagger boards?

That would be centerboards. (or centreboards for those who spell funny.)

Not a bad idea even on a boat that big. Would probably intrude less into cabin space depending on the layout.

[eliboat]

Folding daggerboard.... That's like my favorite term drop keel

[Peter Johnstone]

Centerboards and props/shafts retract flush

[robalex117]

Centerboards are interesting. Gets rid of the daggerboard case through the boat. I assume the centerboard case can fit under the floorboards.

Retractable props/shafts that seems complicated. But I am sure you guys have done your homework.

Centerboards and props/shafts retract flush

[Se7en_speed]

Centerboards and props/shafts retract flush

Peter, do we have any idea what the range is on fully electric drive? or does they system only allow the batteries to shallow cycle before the generator kicks on.

[Peter Johnstone]

Retractable shafts are the real deal that most Volvo teams use, not the hone science projects made by some builders. They cost $$$$.

The hybrid always runs from the Lith Ion battery bank. Range is similar to our diesel equipped boats. 1000 miles when running both, 2000 miles when running one.

[dan360]

I'm interested in what the real benefit of the Diesel Electric hybrid is an sail boat. In a car there are obvious energy re-use opportunities, which are not so present in a yacht. If the range is the same, is the tank the same size and therefore the fuel mileage effectively the same? I think its super cool, but I'm wondering what the benefit is if you're not a WWII submarine :-)

[soma]

The benefits are numerous. I haven't talked to PJ about it, but my read is that if you carry the (heavy) generator amidship, and the (light) electric motor aft you can get the proper prop placement(just forward of the rudder) with great weight distribution (amidship). Plus, you get near silent operation for the 90% of the time you actually use the boat, ie inshore daysails. A totally silent 5 minute motor out of the harbor, main up, sailing. For long periods spent motoring you listen to the rumble of a generator. Massive power regenerating is also possible while sailing. The electric motor will remain in a semi-sealed non-corrosive environment (theoretically) and the generator will be comfortably above the waterline in a sound shield. Maintenance on a generator is always easier, rather than hanging upside down in an engine compartment. Reserve capacity in the battery bank is huge for house loads. Lithium batteries allow fast recharge times. Sail for a few hours and fully charge the batteries, then run the AC all night at anchor off the battery bank. We manage to run one AC at night off battery with a small house bank, but a Li bank will allow all cabins to be cooled at night.

Center boards? Not for me. But if I was starting from scratch I'd definitely want to go diesel hybrid with retractable props.

I'd dreamt of a system like that for a while now. I'm impressed it mates to the V70 style retractable prop system. Beautifully engineered piece of kit, that. I've seem them on ABN Amro and Puma, too, I think. Lots of the RP boats use them. Super slick. At 20+ knots the cavitation of our sail drive legs sounds like a haunted house. Ghostly. And slow.

I'm glad that Peter found someone to be an early adopter. I'm convinced that is the future. My boss is convinced that's the way to go. The early R&D is getting done. Hopefully we'll all benefit eventually.

[SwampFox]

I would like to know what that radome is on the dolphin striker is? I have never seen anything mounted in that way.

[soma]

Here's a link to a retractable prop manufacturer.

http://www.amartech....able-propulsion

[Oxygen Mask]

Center boards? Not for me. .

That bit peaked my interest. Why not, and which do you prefer - daggerboards or permanent keels?

[Oxygen Mask]

I would like to know what that radome is on the dolphin striker is? I have never seen anything mounted in that way.

Looks like radar. If so, could make sense.
Some of the new smaller low energy consumption digital units can provide incredible detail at close range (like showing pilings and docks in a marina) but only if mounted low enough. No radiation hazard like old style units. Typical up high mounts it can't see things that close up. But the, a Flir camera could be even better!

[SwampFox]

It isn't the radar. there is a b&G up high on a pole in the trunk. i was thinking maybe a forward looking radar/sonar or some other technological voodoo i have never heard of. this thing probably goes fast enough to need something looking out for submerged containers. what ever it is i hope it is some black bag shit and not a satellite dish for watching the dr. phil show in the Caribbean.

[soma]

Center boards? Not for me. .

That bit peaked my interest. Why not, and which do you prefer - daggerboards or permanent keels?

If I had my way, I'd like to see curved boards that sorta follow the curve of the hull. I understand the need/desire to get rid of the d. board trunk, but variable aspect ratio is a nice feature of a d. board.

I can't quite wrap my head around swinging centerboards yet.

I'll (hopefully) never sail on a cat with keels.

[Presuming Ed]

I can't quite wrap my head around swinging centerboards yet.

Some history in cats. Engineering them in a 60' cat must, admittedly, but distinctly non-trivial.

[Presuming Ed]

It isn't the radar. there is a b&G up high on a pole in the trunk. i was thinking maybe a forward looking radar/sonar or some other technological voodoo i have never heard of. this thing probably goes fast enough to need something looking out for submerged containers. what ever it is i hope it is some black bag shit and not a satellite dish for watching the dr. phil show in the Caribbean.

Looks the same size and shape as the B&G (Navico) broadband radar scanner aft. If the boat is going for 3Di sails - are they transparent to radio/radar waves?

[Peter Johnstone]

Centerboard benefits:

BALANCE: Instantly balance the boat based on centerboard trim. The 62's and 66's all had minor balance issues when going up/down sail combos. Full main and solent, the balance was perfect. One reef and solent, starting to go neutral. After one reef, then you really need to go to staysail to keep upwind balance. Ditto with screecher. Once it is up, it is getting near lee helm when sheeted tight and pointing high. On the new 60, we have one solent with a reef point. No need to carry two jibs. Depending on whether full main and jib or any combination of reefs, you can dial in the right amount of helm with the push of a button. Ditto with the screecher. The centerboard can go 5 degrees forward of vertical. Normal position is vertical.

EASE OF ADJUSTMENT: The entire load of the CB is taken by the pin. There is much less friction than a daggerboard. You can adjust under load. And with the push of buttons, you can retract your windward board fully for less drag. You do not need to unload the boat to adjust as you do with a daggerboard.

LESS NOISE: Every daggerboard and trunk makes noise offshore when the boat is not powered up. Many groan when under full load. A centerboard makes no noise.

SAME OR LESS DRAG WHEN RACING: On the Gunboats with daggerboards, you'd have both boards about 2/3 down with the screecher, and about halfway up with Asym in VMG mode. The CB should offer the ability to sail around the race course with similar or less drag than the twin daggerboards.

SAFER IN IMPACT SITUATIONS: On passage, a CB is very attractive. If you run up on a container, the worst case scenario is your CB ram sheer pin breaks, and the board retracts. No damage to trunk or board.

CB POSITIONS WHILE SAILING:

Typically down on one side only, adjusted for helm balance. Other side is up. With nearly all sail combinations with main and jib or screecher, this will be ideal. You only need the area of one board. All Gunboats have been designed to sail on one board, but the daggerboard Gunboats never do. As soon as you go to VMG with Asym, one board is about 2/3 up, and the other is fully up.

INTERIOR: Step into the amidships cabins on our new Gunboat 55 or 60 and you will see just how nice a cat cabin can become. These new open cabins are a huge improvement over the earlier boats.

The Tornado is still at the top of the beach cat scene. The centerboards appear to work quite well.

[munt]

dear sir,

Could you give some idea about the shape of the centerboards and how they deploy? Also, how is the trunk opening filled when the board is deployed? And could someone explain why that damned olde tornado is such a great design? thanks,
munt

[diggler]

The centerboard seal is, in my experience, one of the highest maintenance parts of the Tornado. Hope the Gunboat implementation is a substantial improvement over this.

[Oxygen Mask]

I can't quite wrap my head around swinging centerboards yet. .

REally? They've been around a couple hundred years, and work quite well. They work fine on multihulls too.

I agree about not having fixed keels on multis. BAD idea. (Sorry Chris wHite, in this case you're wrong...)

[lake Pee]

[quote name='soma' timestamp='1344395075' post='3816846']
The benefits are numerous. I haven't talked to PJ about it, but my read is that if you carry the (heavy) generator amidship, and the (light) electric motor aft you can get the proper prop placement(just forward of the rudder) with great weight distribution (amidship). Plus, you get near silent operation for the 90% of the time you actually use the boat, ie inshore daysails. A totally silent 5 minute motor out of the harbor, main up, sailing. For long periods spent motoring you listen to the rumble of a generator. Massive power regenerating is also possible while sailing. The electric motor will remain in a semi-sealed non-corrosive environment (theoretically) and the generator will be comfortably above the waterline in a sound shield. Maintenance on a generator is always easier, rather than hanging upside down in an engine compartment. Reserve capacity in the battery bank is huge for house loads. Lithium batteries allow fast recharge times. Sail for a few hours and fully charge the batteries, then run the AC all night at anchor off the battery bank. We manage to run one AC at night off battery with a small house bank, but a Li bank will allow all cabins to be cooled at night.

Center boards? Not for me. But if I was starting from scratch I'd definitely want to go diesel hybrid with retractable props.

I'd dreamt of a system like that for a while now. I'm impressed it mates to the V70 style retractable prop system. Beautifully engineered piece of kit, that. I've seem them on ABN Amro and Puma, too, I think. Lots of the RP boats use them. Super slick. At 20+ knots the cavitation of our sail drive legs sounds like a haunted house. Ghostly. And slow.

I'm glad that Peter found someone to be an early adopter. I'm convinced that is the future. My boss is convinced that's the way to go. The early R&D is getting done. Hopefully we'll all benefit eventually.
[/quote




Diesel electric power plant biggest advantage is that the generator motor always runs at the same RPM, thus it can be fully optimized to run at its most efficient at that RPM.

[float your boat]

There is a lot to like about this boat.

Hybrid is interesting, if a little untested in time and scale. (But that situation won't last long.) And the retractable prop is very cool. Nice gains when sailing here, not to mention easy careening (not that I'd imagine you would want to very often!).

The CB is very interesting and it would seem prima facie a significant design improvement over DB for the growing luxury performance cat concept.

The saloon seems even more 'open' than the 66 too (if that's possible) with its walk through fore glass cockpit doors. The size of the Saloon does however seem overly compromised relative to past models? Where is the big cat spaciousness? Would love to see some interior shots.

She's evidently eavier than say a MC60 but possible gains underwater. Would be very interesting to see these two boats tango sometime!

Great boat!

[eric e]

as a side note

ferdinand porsche designed a petrol-electric hybrid with wheel-hub motors in 1901

then went on to specify diesel-electric in some ww2 designs like the elefant

http://en.wikipedia....ic_transmission