Electric Launch Design optimized for semi-displacement speeds

[In response to HJS on p. 12 ...]

I've worked for naval architects and may wish to re-enter the field as a career act 3, so I don't feel strongly motivated to pay another designer at this time. That could change if I decide to become a boat builder, but right now my goal is to suggest design directions to others, specifically companies with an interest in developing a boat and (electric) power package. What I'm trying to do is launch a collaborative effort or contest so that older people like you, Jurgen (HJS), and I can work with naval architecture students, professors, and other interested parties toward improving the breed.

I see the proposed launch being owned by a club, or as a tender for a superyacht or cruise ship. (We are not talking about a boat for my personal use. I already have three of those, two Phil Bolger designs and a prototype boat I've built to my own very original design in an altogether different category.)

What I'd like to find is a sponsor for the contest. Three I might encourage are:
If the contest were to have a commercial sponsor, the magazines and expos would welcome it, I think. It would likely change my role.

What I'd like you to keep in mind, Jurgen, is that this thread exists in the category:
I like your work, I respect that you're a design professional, and I believe anyone who builds a boat to a designer's plans should be authorized to do so and either pay that designer for that authorization, pay royalties (as agreed by contract), or both. With respect, though, I must ask that you self-monitor whether your remarks are appropriate to the category subtitle "An open forum to generate ideas for collaborative design projects." Thank you.

Stephen Ditmore said:

... my goal is to suggest design directions to others, specifically companies with an interest in developing a boat and (electric) power package. ....

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What is it you think you're offering, and to such companies, that they have not already considered themselves?

It's not about any one feature, nor is it about me. It's about design process. There are mega-yacht companies that have taken an interest in the semi-displacement designs of Perry Van Oossanen, which I believe have merit. The question, as I see it (and as I've said before) is whether there are any recent design insights or tools that would allow improvement on down-east type launch hulls (such as the Oldport 26), and allow a hull to be optimized for carrying passengers, about eight at a time, with electric power.

Stephen Ditmore said:

...It's about design process. ...

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I understand that.

Stephen Ditmore said:

...There are mega-yacht companies that have taken an interest in the semi-displacement designs of Perry Van Oossanen,....

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I think you’re overselling and over thinking this.
A semi-displacement hull, is just that. Nor is it attributed to one person, it is just a hull.

Stephen Ditmore said:

...which I believe have merit....

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Well, that's just you then.

Stephen Ditmore said:

... whether there are any recent design insights or tools that would allow improvement on the down-east type launch hull ...

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No.
Because you’re missing the point of what “design” is….the hull form is the last part of the puzzle of design, not the starting point. And the hull, is what it is, so long as it satisfies the SOR.
There is no magic or black box of hidden tricks up one's sleeve…

Stephen Ditmore said:

..... so I don't feel strongly motivated to pay another designer at this time. ...

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Then you shall have to accept things that are beyond your knowdgle, otherwise you'll go around in circles trying to prove something that does not exist, except in your mind.

Ad Hoc said:

I understand that.

I think you’re overselling and over thinking this.
A semi-displacement hull, is just that. Nor is it attributed to one person, it is just a hull.

Well, that's just you then.

No.
Because you’re missing the point of what “design” is….the hull form is the last part of the puzzle of design, not the starting point. And the hull, is what it is, so long as it satisfies the SOR.
There is no magic or black box of hidden tricks up one's sleeve…

Then you shall have to accept things that are beyond your knowledge, otherwise you'll go around in circles trying to prove something that does not exist, except in your mind.

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Yes, some of us are overly obsessed with hull shape; but especially at semi-displacement speeds, where wave-making is a HUGE factor, it matters. It matters in sailboat racing, of course. So do other things, and I acknowledged that in the contest rules write-up, quoting Olin Stephen. Nevertheless, tank testing played a huge role in the development of a number of America's Cup boats including Dennis Connor's 1987 winner, as did the involvement of theoretical hydrodynamicists such as Carl Scragg in Connor's 1987 effort and Perry van Oossanen's father, Peter van Oossanen, in the Australian '83 effort that defeated Connor.

In Australia, INCAT Crowther's principle is the son of a well known sailing catamaran designer. In the UK, Uffa Fox and Nigel Irens, both sailboat designers, have designed launches. HullVane (a Van Oossanen effort) resembles the International 14 rudder hydrofoils by sailboat designer Paul Bieker.

It has been a major effort at the US Navy's David Taylor Model Ship basin to incorporate what they've learned by putting flaps on ships into clean-sheet-of-paper stern shapes, and their CFD analysis indicates what happens at the stern should influence the shape farther forward. This is also claimed by Van Oossanen and the Hull Vane people.

I think it makes sense to make sure one's hull shape is good before building either a large vessel, or a mold for multiple small ones. Especially when talking about electric power, throwing more horsepower at the problem is a poor substitute for good hull design IMHO. We've overpopulated the recreational market with "wake boats" designed to make LARGE wakes. I want to see some real-world development of low wash hulls, and I don't think asking what we've learned in the last 60 years is a crazy question.

Hhhmmmm….you still don’t get it.
Okay, let me put this into a language you may understand.

So, you go into a restaurant, sit down...and a waiter approaches you:
You – may I have the menu please
Waiter – we don’t have one, as you can have whatever you want.

You – ok, a grilled salmon with asparagus on the side.
Waiter – perfect choice, how much can you pay for this?

You – oh, I only have $25 in my wallet
Waiter – not a problem sir, we can make to suit.

As your plate of salmon arrives, just before you start to eat, you notice other dinners, with a similar meal. Their plates are the same size as yours, but their salmon is twice the size of yours.

You then notice the couple sat next to you, they are served with a nice juicy Kobe Beef steak, the smell filling the room grabbing everyone attention and other dinners gasping at the wonder of it.
Some literally stop eating their meal, and focus on the table with the steak...push their own aside.

You – Waiter, why is their salmon so much bigger than mine?
Waiter – they had more money to offer so they got a bigger fillet.

You – where did that Kobe beef come from, it looks amazing?
Waiter – special order, they just fancied something different, as they are fed up with eating fish all the time, like everyone else. So asked the chef to surprise them, and offered extra money for it.

All your questions about boat design are this.
You fail to grasp that clients get what they asked for, what they can afford, and more importantly, unless specifically asked for something different, and backed up my funds for it, always get the same.

So the smart restauranteur takes lessons from this experience, aggregates those lessons, and from time-to-time introduces something new to the menu to see how it does. Perhaps people have been coming in who are on special diets. A pattern is recognized, and dishes are introduced to cater to those customers.

A food writer then suggests - let's have a contest for best restaurant offerings that meet certain criteria for, say, diabetics.

What do you think of this offering, AdHoc? Zin Boats Z11 Electric Superyacht Tender Collaboration | News | Raymarine https://www.raymarine.com/en-us/about-raymarine/newsroom/zin-boats-z11-electric-superyacht-tender. It seems to be the result of some sort of collaboration.

Stephen Ditmore said:

....A food writer then suggests - let's have a contest for best restaurant offerings that meet certain criteria for, say, diabetics.....

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You start off on the right track, then shot yourself in the foot.
There is no "contest"...one gets what one pays for. Since a contest, becomes the SOR....which is at variance with an SOR for a Design.

Stephen Ditmore said:

....What do you think of this offering, AdHoc? ...

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With respect to what?

Every boat that exists presumably started as an SOR. I'm suggesting one criterion for evaluating today's 'menu' of boats, and thinking about tomorrow's, is whether they improve on what came before in a way that is a useful leveraging of current technologies and needs/desires.

In the case of the restaurant, if a group walks in, and the meat & fish eaters leave happy, but the vegans and vegetarians don't, that group might never be back.

A truism is an obvious truth. I'm suggesting we have a conversation about boats, not truisms. So I place before you an electric boat; what do you think of it?

Stephen Ditmore said:

.... So I place before you an electric boat; what do you think of it?

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What do I think...?
There are boats powered by diesel engines.
There are boats powered by the wind.
So...there are boats powered by electricity...

Your point being?

Again, you respond with a truism. I'm trying to draw you into saying something relevant (instead of trying to make me the issue).

One thing you've said is that an aluminum boat will be lighter. Of composites I'll say that depends on the reinforcement & resin used, and other factors. We might be able to learn these things about the Z11.

A question I might ask is: if you were to build a Z11-like boat in welded aluminum, would a perfectly fair, yacht quality finish be achievable without adding weight in the form of fairing compound?

I see you've posted an interesting answer to an aluminum alloy question at Whats marine aluminum alloy is better Sealium or Alustar? https://www.boatdesign.net/threads/whats-marine-aluminum-alloy-is-better-sealium-or-alustar.46477/. Your response doesn't imply there's NEVER a case where a special alloy would save weight in small boat construction, but it's an interesting insight, for which I thank you.

The Z11's planing hull may be appropriate for a yacht tender. Would it be appropriate for an electric club launch that spends more time operating in-harbor? What would it take to design a boat suitable to both purposes? Might it make sense to do that rather than store a yacht-club launch on land half the year? In the yacht-tender role, might a dual-purpose boat be better suited to ferrying large numbers of people to shore in rough conditions than a planing boat?

I'd like to offer this observation concerning batteries: second generation sodium-ion batteries are just now going into production from a Chinese company called CATL. Research on them has been done at universities in Texas, so I don't think they are an entirely Chinese thing. They don't suffer from lithium plating in cold weather, among other advantages.

I have not been able to learn the chemistry of the Duracell batteries on INCAT's Hull 096. Does anyone know?

Stephen Ditmore said:

Again, you respond with a truism....

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Because that is what it is, a statement of fact.
What you want, is a subjective opine…the two are poles apart and yet you consistently attempt to conflate the two because you don’t understand that they are different, not the same. And that is at the heart of why you simply don’t understand Design.

You’re firing off questions what about this, or what about that….well, what about it?

This sums it up:

Stephen Ditmore said:

...I have not been able to learn the chemistry of the Duracell batteries on INCAT's Hull 096. Does anyone know?

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Who cares?
Honestly who cares?....as a naval architect all I need to know about a battery is its:
1 weight
2 size
3 energy density (kW/h)
4 DoD, SoC
5 means to prevent an exothermic reaction
6 means for fixing to the structure
7 means of cooling
8 sales support
9 certification
(This is not an exhaustive list....)

Beyond that, I simply don’t care if it is made of switz cheese or sand or ice cream. In the context of Design, it matters little.
Do I care what the metal/alloy of the engine is, no (so long as it ticks the boxes of weight, size power, certs etc), or the side linings, no (so long as it ticks the box of weight, fire certs, ease of installation)...etc etc

You are constantly looking at bright shinny things - with the misguided notation that “it” defines something new or different, and conflate it with – this is revolutionary why is no one else doing this.

Stephen Ditmore said:

...One thing you've said is that an aluminum boat will be lighter....

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Lighter than what?

Ad Hoc said:

Lighter than what?

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Go find what you said yourself, AdHoc. It's a shame you'd rather waste everyone's time than contribute anything useful to a discussion. The point you're making by asking that was my meaning.

Stephen Ditmore said:

Go find what you said yourself, AdHoc. It's a shame you'd rather waste everyone's time than contribute anything useful to a discussion.

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This is, again, at the heart of your quires.
You provide zero context and yet offer a plethora of questions all unrelated, thing thinking they are the same.

You don't understand what Design is...fine, it is clear to all, then don't waste bandwidth repeating the same point time and time again.
It wont change your understanding by constant repetition.