Designing & Building Hammerhead

Thanks McArthur!

The idea is that if we can act on movement quicker the stabs need less swing-out, resulting in less overall drag.

The surface area / square feet that the stabs add have already been incorporated in the fuel usage calculations. Not the additional drag of them functioning, though.

Regards, Edwin.

Phew! We have been writing texts for the website all day yesterday. The website designer is happy though. More renderings coming through. With a focus on the guest cabin now.

The new website should be up and running by the end of this year. It will tell our story, introduce the boat we are working on, and share updates on the build project via a blog and videos.

Very exciting!

Regards, Edwin & Veronika.

Here's a concept rendering of the homepage.

Regards, Edwin.

Looks good.
Perhaps a person somewhere in the picture, cockpit or bow, to show scale?

The LM65h is not prominent enough either.

I wouldn't say "Our ship" as it's too personal and indicates you only have one! Maybe put the LM65h on the white instead of "our ship"?

Also the company "Liquid Management" for some reason made me think liquid assets and a negative connotation about assets that are paper-only, but have no reality (ie. fraud). Just one data point, but the name was a negative.

Thanks. Good feedback!

Regards, Edwin.

Railing and bollards ... and initial anker arrangement!

Regards, Edwin.

How do you raise/lower the anchor without it whacking the stem at the waterline?

Hi Sean,

Not sure I can explain it, since English isn't my mother tongue. There is a structure that moves forward. Then the anchor is lowered.

Regards, Edwin.

First concept renderings of the forward cabin. Thicker mattresses will be added. As well as a small desk/chair option, and straps to hold the upper bed in place (and the person sleeping there.

The sofa can be turned into two additional bunks. The room is designed for one or two guests up to a couple with kids. That's about the maximum number of guests we foresee in our future sailing adventures.

Regards, Edwin.

aft deck lay-out

The aft deck lay-out is slowly coming together!

Regards, Edwin & Veronika.

In spring we'll be convoy sailing to London, so from the Netherlands via the North Sea coast to Belgium, then France, and then cross over to the UK. From there to London for a 3 day city stay-over. After that we'll return back to the Netherlands. A 2 1/2 week program together with 19 other sail boats and motor yachts. We are SO looking forward to the experience!

Regards, Edwin & Veronika.

Something new ...

We are working on something new. Anyone any idea on what it is?

We wish y'all a great weekend!

Regards, Edwin & Veronika.

Total guess: stern anchoring pendant of some kind?

Retractable passerelle?

Teak decks?
Is it really all gray and white on the inside?

Hi Dan,

These are technical drawings. It is the forepeak stowage area and it will indeed be relatively unfinished. The decks will get cork decks probably.

Hi Knotyet,

Thanks for chiming in. What we are designing is a kite system. You are looking at the engine and little mast for that application.

Regards, Edwin & Veronika.

Edwin you must be an engineer. You give attention to detail to every element of your design. Your boat is like a science experiment [emoji846]

Engineer, inventor, and change manager with a scientific education.

Not saying it makes life easier. It does make it quite interesting, though! Even though "tiring" might also be very applicable.

I can't look at things without thinking "now, why is that put together like that?", Mako. Not saying that's good or bad. It's just who I am.

Regards, Edwin.

Salty Pelican said:

Engineer, inventor, and change manager with a scientific education.

Not saying it makes life easier. It does make it quite interesting, though! Even though "tiring" might also be very applicable.

I can't look at things without thinking "now, why is that put together like that?", Mako. Not saying that's good or bad. It's just who I am.

Regards, Edwin.

Click to expand...

You might want to put the engineer talents to work doing some calcs on the usefulness of that kite. Kites and various sail additions to recreational power boats have been tried lots of times and I’ve yet to see anyone that has been able to declare the addition measurably beneficial, let alone worth the cost and trouble in this application. Might be worth studying previous efforts of others (if you haven’t done so already) before committing to that addition.

Sometimes creativity conflicts with functionality and the KISS principal.

The whole project is certainly an opportunity to create your own vision of the perfect boat. That alone might be the best reason to do it. Looks like great fun.

Thanks Guy!

Yeah, you are spot on. There is always that trade-off. I love the "less is more" approach to design. I am also a big fan of integrating functionalities, where one item has multiple roles. Like the electric engine being both back-up engine and back-up generator. Or like the gen-set being both generator and optioning as back-up propulsion power supply.

We will make the kite optional. In such a way that it can be retrofitted. But since it adds to the whole picture of efficiency, autonomy, and long distance sailing, especially because we expect to attract attention from former/aging sailors, it is too good an option not to explore. Or so it feels to us. Also see the aft/outside steering position, that finds inspiration in sail boat design.

Our first calculations show that in moderate winds it'll take the ship to 6 knots. If we replace the prop with something that folds, or if we add 1 kWh to a non-folding prop, that'll be 7 knots. Granted, most of the sailing will be before the wind. It'll work quite nicely, I expect, with winds from behind up to 30 degrees angles off-center, not more.

It wouldn't work on most motor yachts, but please remember our extreme focus on designing an underwater-ship that is very efficient.

Also, the hole that holds the mast serves as the hole that holds the mobile davids. The mast also has an extra eye, so that it can keep an optional sunshade in place.

Regards, Edwin.

Salty Pelican said:

It wouldn't work on most motor yachts, but please remember our extreme focus on designing an underwater-ship that is very efficient.

Click to expand...

My own opinion here, and I mean this with all respect and deference to your own priorities and choices, but I think this is very much the wrong focus for 99% of boaters. I think it only makes sense if:



1) You are doing it primarily as a science experiment to explore efficiencies are various designs, or


2) You intend to be at sea on passage nearly all of the time.


Only you can speak to either of these goals, but I do know that the most intrepid cruisers I know, including those who have ventured around the world, spend well less than 5% of their time on passages.


As a result, power cruising boats have evolved to where they are today. In Bebe's pioneering days when he was trying to prove the viability of long distance power cruising, his boats looked like sail boats with the masts removed and larger engines and fuel tanks installed. With no need to watch sails all the time from an open, aft cockpit, those wet, cold, uncomfortable helm stations moved inside. But now the helm and house were sharing the same space creating a conflict over lighting during night operations. So the helm moved to a pilot house. And all that extra fuel stored down low, along with the engine and other machinery, had the fortuitous effect of moving the salon up to or above the water line, and everyone realized how nice it was to no longer be living in a cave. Then with the helm moved out of the cockpit, people realized that was a really nice space for fishing, or just hanging out to enjoy the outside when the weather is nice. It also makes for a convenient boarding area. Then people realized that when the weather is nice, it's great to operate from outside, so the fly bridge was born. And it sure is a nice view from up there, plus a great place to just hang out and enjoy the view. And along the way people realized that there isn't really that much difference in operating cost if you have a wider beam, but you sure can have a lot more living space and a more comfortable boat, so boats got wider.


If you look around, I think there are a lot of reasons why power cruising boats are set up the way they are, and why they out-number FPB-style boats probably a thousand to one.



And on folding props, don't be tempted. The noise and vibration from a folding prop is massive compared to a properly sized fixed pitch prop. They are a necessary compromise on a sail boat, but not on a power boat. Smooth and quiet is preferable, in my opinion.

Thanks for sharing, TT!

Yes, the boat is designed to be sailing (or motoring) most of the time. Yes, the standard cruiser/trawler sales heavily outweigh FPB-like designs. Yes, I think Bebe was spot on with his design priorities.

I feel - personally, so for me - that a way back to his original ideas would be a step forward. Especially since modern technology makes it much more viable. My focus - like his was - is on crossing oceans. And on making it a safe and totally enjoyable affair.

Regards, Edwin.

... and wider ships do come at a hefty efficiency cost.

Regards, Edwin.

Salty Pelican said:

Our first calculations show that in moderate winds it'll take the ship to 6 knots.

Click to expand...

I’m not a sailor and my only technical degree is in hillbilly engineering, but I’ll still say getting that boat to run 6kts with a kite alone will be tough to achieve.

kite calculations

Here are som initial calculations, gentlemen. A work in progress, so still to be fine-tuned. But the grit of it goes as follows:

At a wind difference between sailboat and wind of 5 m/s (5 meters per second or 17 feet per second), a square meter of sail produces about 1 hp. The 1 hp per m2 includes the inefficiency of the ship being pushed over. Keeping a sailboat at angle costs energy.

Kites deliver a higher output per m2 than sails. Research from Delft University shows at least an improvement to 1 kW per m2 or 1.36 hp per m2. The efficiency gain comes from a kite-driven device usually not needing a long arm (aka mast), and the kite propulsion system thus creating less leverage (hope that's the right word), resulting in the generation of more net energy.

In other words: less power is lost to keeping the vessel at an angle, resulting in better efficiency numbers. Hence the kite outperforming the traditional sail by at least 36%.

Now that we know that a kite produces at least 1.36 hp per m2, let's investigate how much power is needed to propel our ship at 6 knots. The power needed is 13 hp (see picture of the relevant resistance-to-power chart for our ship's design underneath).

Knowing the power delivery of a kite per m2, the power that's needed to propel our ship at 6 knots, we can now make a calculation of how big the kite needs to be. 13 hp divided by 1.36 equals ... about 9 m2.

Regards, Edwin.

On ocean passage have used
Double head sails no main
Asymmetric and symmetric spinnakers
Bought and used a parasailor on last boat
Codes 0 and 1

The universal difficulty is all winds vary 10-20 degrees in direction and all winds vary in intensity. Degree of these variations vary in degree but are always present to some degree. So apparent wind varies in direction and intensity. But there’s also always a fall in the speed of the apparent wind the faster you go.. For efficiency you need to trim. This remains true for kites. For a fully manned race boat that’s a non issue. For a cruising boat that’s a PIA. Many cruisers get around this by not going DDW. There’s is a fall in efficiency but by not going DDW the sail plan is more tolerant of minor fluctuations in direction and apparent wind speed. This is routinely seen as a improved VMG as on passage as long boards are possible. Gyping at change of watch isn’t onerous. Kites are less tolerant of going to a far reach and do require more attention if you do.
So think kites are a viable get home fallback but also think it will end up something you have but don’t use. We spent a bunch of boat bucks on our Parasailor. Only used it when there were at least 3 experienced sailors on board. Ended up using double headsails no main 95% of the time when going down wind. Especially on passage as with reliable roller furling pull two strings and no rags up. That could be done by one crew so thought that the safest set up for passage.

Forgetting headers and lifts going down wind there’s holes. That sail hits a lull or gets back winded from inattention it will collapse. Maybe you save it before it gets wet. Maybe not. Then given boat speed will only slow gradually you have sail and string under the boat. Not fun. Sure hope for the best but plan for the worst. Personally wouldn’t fly a kite on passage in powercraft except in anger(get home) or extremely limited settings.

We see the kite addition as something that can be used on longer stretches, taking advantage of trade winds, for instance.

Currently, we are talking to several ship yards to see which one is best suited to help us build the first LM65h! Very exciting stuff!

Regards, Edwin & Veronika.

Edwin
A few years ago we met up with an aluminum 65' sailing vessel called Thor. Thor is an amazing boat and owned by a serious globe girdling couple. When looking at your post#1 it checks a lot of the boxes. Google sailthor.com for details.

Thanks! We'll look her up!

Regards, Edwin & Veronika.

Updated picture LM65h

Here's an updated picture. We added windows to the back of the main room. This makes it possible to sit on the bench on the outside aft deck and still maintain vision on what happens in front of the boat.

The dingy is also added. As well as three mobile davids systems. That's just to see how positioning would work. In reality, there'll be only one davids system that can be applied on multiple locations.

Regards, Edwin & Veronika.