Looking for a long range expedition aluminum power catamaran design

[starcmr]

Hey! I'm new to the forum but I've been lurking for a while as I've been searching for something suitable, so I figured I might ask you all to maybe point me in the right direction.

My partner and I are planning early retirement, and we've always shared a passion for adventure and traveling so we wanted to segue into seafaring and exploration of the world through our own eyes. To this end we were looking to find a go anywhere long-range fuel-efficient cruiser that would serve as a platform to do everything out of. It seems a lot of production vessels focus on things we frankly don't care about, so we figure that going for something custom for our needs is a reasonable strategy.

To begin with we don't care about luxury finishes or 15 different ways to entertain or host parties or rely on a bunch of crew. We want an owner-operator focused vessel that leans more towards commercial/military ruggedness and utilitarian interiors and emphasizes ease of maintenance and access to systems and operability. We're both tech savvy engineers (albeit from fields not directly related to the marine industry) and part of the appeal for us is to learning to maintain and work on our ship as necessary, as well as DIY systems and integrations. We want excellent seakeeping and safety for ocean crossings, and the capacity for redundant systems. We intend to spend most of our time cruising or at anchor, with minimal time at marinas.

We want a high degree of autonomy and would like to be able to go months without needing to resupply. We also (more so me than her) have a bit of prepper tendencies and would like this to feel more of a home base or moving fortress rather than a luxury yacht, which means no real need for a sun decks or open spaces, let alone dozens, or huge windows everywhere or a flybridge Equiti Metro Station. I'd rather have solar power generation instead. One of our goals is to optimize fuel efficiency and fuel capacity alongside weight to maximize operational range, so while we want and are open to springing for as much space as possible, we want to keep it manageable by the two of us. We don't want to dedicate a lot of resources to guests seeing as how we will be traveling alone most of the time so our spaces would always the be the priority, and we'd just have nominal accommodation for maybe 4 other guests.

We opted for a catamaran due to their speed, stability and fuel efficiency compared to monohull displacement trawler, which we've considered but sacrifices too much efficiency to space.

We do want the ability to store and launch some toys, like an amphibious gyrocopter, a mini submarine, kayaks, etc. aside from the usual tender.

I'm sure more specifics escape me right now, but I hope that gives a general idea of what we have in mind. Ideally we'd like to find some designs or a designer/NA that closely aligns with these goals so we can work with them to bring about this vision as quickly and as efficiently as possible, since it's something we've been wanting to do for some time now and would love to see it realized. If this is something you all could help us with, or if there's something else we should be doing, please let us know!

Look into expedition-style catamarans from Circa Marine, McConaghy, or Bering Yachts. For custom designs, consider naval architects like Incat Crowther or Damen Yachting. Prioritize aluminum or steel construction for durability, and optimize solar and fuel efficiency for extended autonomy. If modifying an existing platform, check out FPB series or long-range power cats.

 

[skaraborgcraft]

This looks pretty cool if it's possible to fit the toys and enclose the flybridge, but I don't see any details about propulsion or efficiency. Is that usually part of the paid study plans?

It could be, it would be worthwhile sending them an email and asking. You could reach out to the members already named, it sounds like you would benefit from a project manager.

 

[skaraborgcraft]

semi displacement catamarans — Jutson Marine Design https://www.powercatamaran.ca/semi-displacement-catamarans

I was going to comment on the rendering of the boat perfectly on its lines with a helicopter on deck, only to find that a Hughes MD530 weighs less than the 800kg submersible! You could cable launch a gyro while underway, like they used to on subs.

 

[fallguy]

I have a small 10M powercat. I can’t really imagine running anything bigger than 20M without a crew of at least one more person. It is just pretty tricky maneuvering that boat in a harbor and amazing how easily to lose bearings with no visibility to the bow edges. Maybe some cameras could help, but running lines on an 80 footer is really a job for minimum 3, one helm and two to run poles and lines. Our boat is easy for 2, but I have a good feel for where it’d get hairy.

 

[CocoonCruisers]

Cool thread, facing the complexity in real dialogue

Wouldn't this SOR match a workboat cat conversion ?
- They are made to be loaded, used and abused.
- Most are relatively simple builds, and user mods are expected/anticipated in professional use.
- Sometimes they get sold for cheap in bancrupcies or fishing, windpower or whatever other field's policy reversals. Or just because the engines reach end of life, and a repower exceeds the value of the boat.
- They will typically not be made for running efficiency out of the box, but as long as Silvard remains happy with hull speed, perhaps a downpowering swap and a modest stern mod could get him there. (Some might even be narrow enough to run reasonably well on one engine, using folding or feathering props - another relatively cheap update. And from there he'd almost halve his engine hours.)
- Many have a sizable open rear deck and a little crane already in place.

You'd need a Naval Architect though, not only for the mods but also for recertification into the (typically far less constraining) pleasure marine regs.

 

[gonzo]

I think that if this is a boat to cruise for a couple of decades you should consider your physical capabilites in the future. A size that is manageable today will probably won't be in 15 years. We often forget our bodies are older than what we feel like mentally.

 

[Silvard]

Hello friends!

Thanks again for all your input and help. We've been busy refining and fleshing out a SOR as well as adjusting our requirements and expectations based on your very helpful feedback. For instance we decided to eschew the idea of the submersible and will switch to much more convenient ROVs instead; we will still SCUBA anyway. We have also reached out to a naval architect (and even a potential shipyard) and plan to float the idea around to a few more once we have our detailed SOR.

Look into expedition-style catamarans from Circa Marine, McConaghy, or Bering Yachts. For custom designs, consider naval architects like Incat Crowther or Damen Yachting. Prioritize aluminum or steel construction for durability, and optimize solar and fuel efficiency for extended autonomy. If modifying an existing platform, check out FPB series or long-range power cats.

We've considered it but they all seem to work at a scale way beyond what we are or are looking for.

I was going to comment on the rendering of the boat perfectly on its lines with a helicopter on deck, only to find that a Hughes MD530 weighs less than the 800kg submersible! You could cable launch a gyro while underway, like they used to on subs.

Yeah! Gyros, like a lot of sports aircraft, are really lightweight.

I have a small 10M powercat. I can’t really imagine running anything bigger than 20M without a crew of at least one more person. It is just pretty tricky maneuvering that boat in a harbor and amazing how easily to lose bearings with no visibility to the bow edges. Maybe some cameras could help, but running lines on an 80 footer is really a job for minimum 3, one helm and two to run poles and lines. Our boat is easy for 2, but I have a good feel for where it’d get hairy.

I think that if this is a boat to cruise for a couple of decades you should consider your physical capabilites in the future. A size that is manageable today will probably won't be in 15 years. We often forget our bodies are older than what we feel like mentally.

This is a reasonable concern and one we have thought about quite a bit. Even if we're planning on minimizing docking or marina time or super tight inland waterways, we still want to leverage tech to help us with this, such as 360 camera views and thrusters and joystick control for low speed navigation. We also envision a future where crew, even if not professional per se, might be more ubiquitous.

We're still 38 and pretty confident in our current physical abilities, which is why we want to do this ASAP. If we can set figurative sail at 40 and travel for 20 years, we'd still be spry 60 year olds, hopefully.

Cool thread, facing the complexity in real dialogue

Wouldn't this SOR match a workboat cat conversion ?
- They are made to be loaded, used and abused.
- Most are relatively simple builds, and user mods are expected/anticipated in professional use.
- Sometimes they get sold for cheap in bancrupcies or fishing, windpower or whatever other field's policy reversals. Or just because the engines reach end of life, and a repower exceeds the value of the boat.
- They will typically not be made for running efficiency out of the box, but as long as Silvard remains happy with hull speed, perhaps a downpowering swap and a modest stern mod could get him there. (Some might even be narrow enough to run reasonably well on one engine, using folding or feathering props - another relatively cheap update. And from there he'd almost halve his engine hours.)
- Many have a sizable open rear deck and a little crane already in place.

You'd need a Naval Architect though, not only for the mods but also for recertification into the (typically far less constraining) pleasure marine regs.

This would be great if we could find the right platform, but we've had no such luck there.

On a separate note we've been curious about some things that've been trying to figure out as we work on our SOR, and we intend to keep asking about those here (thanks again in advance for all your help). We want to avoid big and heavy articulating cranes that seem common on boats and yachts and want to use some sort of collapsible or retractable or even rollable ramp and winches for the gyro and something like this:Loading Systems | EasyLoad - loading crane for vans and trailers - MAD Automotive for our aft deck in lieu of a crane or tender davits. What are the tradeoffs that we might be missing? Also does anyone know of a marine version of these solutions that aren't designed for superyachts? I'm not even sure what are the right technical terms for this type of crane on a boat.

 

[skaraborgcraft]

If you are letting go the submersible, that opens up some lighter cat options for you, which is better all round in many ways.

I gave a link in a previous post to a supplier of similar crane/hoists. If you want simple, you just need an RSJ beam on a swivel and a chain hoist, no electrics or hydraulics to worry about, save yourself $20k.

 

[Silvard]

If you are letting go the submersible, that opens up some lighter cat options for you, which is better all round in many ways.

I gave a link in a previous post to a supplier of similar crane/hoists. If you want simple, you just need an RSJ beam on a swivel and a chain hoist, no electrics or hydraulics to worry about, save yourself $20k.

Sorry I can't find that post, could you please post it again?

 

[skaraborgcraft]

My bad..... I didnt not supply a link.

Deck cranes - Hydromar

Davits and Cranes Superyachts - Nautical Structures

 

[comfisherman]

Mph makes a duesy of a little long reach knuckle crane that works on these extreme beam fishing boats. Might be a good option for a cat. They have some small ones that are quite popular without being to massive.

38 is young enough to have the ability to learn efficient docking, and will be mobile for likely another 25 years. Its going to be interesting to see what the next 25 years brings.

Still remember installing the echotec green screen plotters with the furuno gps units. I was a kid at the time but still remember how much my grandfather raved about it's superiority to loran for accuracy. By time I was an adult, we had ecds charting and early gps compass. Now even my little boat has 3d bathy generation, fly by wire shifting and steering and a gps compass that can drive better than I can. Grandad started with cable shifting and chain to rope steering, now we have a station on deck for both shifting and steering and now the proportional control bowthruster....

Being short handed isn't what it used to be...

 

[ropf]

For the work that we do want to hire and materials we have 0 intention of doing it in high cost of living areas like the US. ... What are they (and us) missing?

Your plans are based on the strength and stability of the US dollar - and the poorness of other countries - what may be not given facts tomorrow. The United States are no longer a safe haven for capital anymore, and more and more countries dissolve themselves from the dollar system. It's a time of Black Swans flying.

 

[montero]

"Sails are expensive, daggerboards are expensive, I'm too old for dramas on the water"
This is not an exact quote from this forum, I hope I haven't lost the meaning. This is the most logical direction for OP.

 

[Skybuy]

So what happened here?? I created an account just to post this!

I have a very similar need. Working on quotes from some boat builders/designers. I have a couple quotes from Archipelago for a 52 and 63 aluminum cat. I don’t have as many toys that I need to haul around but I do have kids to haul safely. Also, budget for me is around $2m.

Anyone have an update!? I’m endlessly searching for brokerage yachts vs affordable new builds. My goal is to set sail on our first trip within about 18months.

 

[montero]

Maybe look after much cheaper cats . Save your money for other pleasures . Mumby from Philippnes ? Chinese shipyards ?