[YachtForums]

Hello Carl!

A quick note to let you know that the 86ft Powercat Pacific Harmony has been
sold. The new owner is enjoying his new boat and is cruising the Caribbean.
We are working on new designs, a 55 foot Powercat that will be a fully
tooled production boat. The new boat will be designed for live-aboard
retired couples who want an easy to manage, safe, long range Powercat which
they can cruise the world in comfort. It will be offered with 4 exterior
cosmetic styling variations on a standardised hull and interior.
Once yard costings and a complete business plan are finished over the coming
months we will be in a better position to report more on it. It will appear
on the website when this is finalised.

Till then, thanks for the interest in our previous work and happy boating.

John Winter
Winter Yachts

[catmando]

www.winteryachts.com

This is a very nice boat, but why would they mount the engines so far forward?? I would mount them rearward using waterjet drives for shallow draft.

[TRY]

Thanks Carl,

This confirms my views on future market development for larger cats!

[YachtForums]

Originally Posted by catmando

This is a very nice boat, but why would they mount the engines so far forward?? I would mount them rearward using waterjet drives for shallow draft.

Good observation Catman! And an interesting question. There are a couple of reasons why the engines are (and appear) to be mounted further forward than one might expect...

A primary reason is Center of Gravity, but secondary... if you study the artist rendering below, you will see the hull tapers to the exit of the shafts. The props are placed immediately behind this point. The space leading up the buttocks of each sponson becomes progressively more narrow, thus reducing interior engine room width/space. The recessed, flat under-side of the aft deck/swim platform extends beyond this point and serves two purposes... additional lateral stability and a partial planing surface.

What is NOT shown in the original construction picture is the bulbous bow extensions that were added to each sponson. I've attached another picture showing their later incorporation. The bulbs were added after the initial sea-trials, when it was determined they would help the cat run flatter and reduce pitching in various water conditions.

The bow picture below also reflects the relatively narrow cross-section of the sponsons, which is one of the reasons the sponsons have an extended flat running surface under the swim platform. (increased stability)

Pacific Harmony is not typical cat hull configuration. It is actually a displacement hull with wave-peircing attributes. Here is a link that better defines the concept...

http://www.winteryachts.com/catamara...ny_design.html

Waterjets could be an option and the narrow cross-section of each sponson would lend itself to a high level of maneuverability, as there is no resistence to backwash.

[catmando]

I must say I didn't see the "buttocks taper". I like another kind of buttocks taper. But that does explain the engine placement a little better than the CG you mentioned(although that was probably a factor as well).

And yes I saw the bulbs on the website and knew there had to be a very good reason for them. I also wondered whether it was semi-displacement or full displacement.

I'm glad to read that you think waterjets could be used in that engine-forward configuration. I assume very long driveshafts would be invovled? I thought that with propellers the draft was too deep for a cat and it would have a hard time navigating the Bahamas.

[catmando]

Originally Posted by TRY

Thanks Carl,

This confirms my views on future market development for larger cats!

Yes no doubt. If the interior volume of your cat can be brought up close to that of a monohull of comparable length, your boat will surely sell. I think the yacht-buying public is become better-educated about multihulls and their advantages. And I like your 100' length more than the Winter cat's 86'.

[YachtForums]

Originally Posted by catmando

I'm glad to read that you think waterjets could be used in that engine-forward configuration. I assume very long driveshafts would be invovled? I thought that with propellers the draft was too deep for a cat and it would have a hard time navigating the Bahamas.

In the case of Pacific Harmony's sponson design, the engines would NEED to remain forward in order to accomodate the intake gullet of the jet pumps. The only problem I foresee is the buttocks of the sponsons would need be flat in order to mount the venturis and thrust directors. This would diminish displacement efficiency.

Because Pac Harm has a deep draft, due to the narrow cross section of the sponsons, the props are not exposed beneath dead bottom plane. This protects the running gear in the shallows.

John Winter and Malcolm Tennant have done a remarkable job with this hull. It's extremely efficient. With twin 800 hp Cats (not alot of HP for an 86' boat!), they are achieving 26 knots, with a 20 knot cruise. Backing off, a 13-15 knot cruise consumes less than half of an equivilent size monohull. And that same 13-15 knots, is the typical speed of Pac Harm's displacement counterparts.

Fast, fuel efficient, stabile. It's all good.

But... there's always a trade-off. Interior, below deck space favors the monohull. And if you think engine rooms are tight on most yachts... try to service an engine located in a sponson! The mechanic better be an ex-racehorse jockey. (a little humor, don't take me to task!)

[catmando]

I don't mind the jockey, but those sponson buttocks have got to go.

[catmando]

...and of course you don't have to sell me on the cat's efficiency. It's very fast, fuel-efficient and STABLE.

[TRY]

The interior volume of a catamaran is always 30% more compared to a monhull of the same length.
The "missing" volume between the hulls is more than compensated by the extra square metrage on each deck above the waterline.
It's a simple question to re-arrange the layouts. Staterooms on the main deck, technicals and crew quarters in the hulls.
How to do this? Ask Lars!

[capitan_buzo]

For me, the perfect yacht would be a more refined Octopus. It would be bigger, widder, and taller and would be a grey or some shade of Black. It would have more power and it would have 4 heli-pads like a project from Lurssen I heard of. I don't think the yacht will every come to life though. I will try to come up with the specs latter.

[TRY]

The ex-USSR Black Sea fleet still has an aircraft carrier up for sale.

[capitan_buzo]

Do you have a link?

[Codger]

Originally Posted by capitan_buzo

For me, the perfect yacht would be a more refined Octopus. It would be bigger, widder, and taller and would be a grey or some shade of Black. It would have more power and it would have 4 heli-pads like a project from Lurssen I heard of. I don't think the yacht will every come to life though. I will try to come up with the specs latter.

The perfect yacht is still to be built


The grey and more power is talking to me but 4 heli-pads........ Ah, a Flying Boat.

Even 4 Sikorsky S-64 couldn't do it.

[AMG]

Originally Posted by Codger

The perfect yacht is still to be built

And I still wait for the call...

/Lars