Retrofitting Pod Drive to a Sailing Catamaran

[smj]

Are you saying the gps and autopilot would dock the boat?

[Catalysis]

Originally Posted by smj

Are you saying the gps and autopilot would dock the boat?

No, but the gps would hold position while picking up a mooring.

I am also planning on adding remote control to allow a person to stand on the transom while docking. My current cat has a Raymarine remote autopilot which we use to steer while sitting on the tramp in uncrowded waters - so it's really just an extension of that concept.

[sandy daugherty]

As I read the comments here, what you are asking is possible, and the majority are asking why you would want to.
Two engines on a catamaran do greatly enhance maneuverablilty, but do not provide a means for powering beamwise, athwartship, or sideways (depending on your preference of terms.)

This is desirable in a number of common situations: sliding into a narrow space in adverse breezes or current, joining a circle raft while letting an anchor rode out, or just holding a position at a dock while tying up single handed. And there are accepted practices for doing all the above using great skill and competent crew.

I have toyed with the idea of mounting midship outboards on diagonal "transoms" and turning one or both to thrust laterally, or z pods on a larger cat. If you think about it a while, and recall some mishaps with confused crew, you might get to like the idea.

[Catalysis]

Yes Sandy I have also been considering retractable 360 rotatable thrusters but haven't found any yet. Do you know of any?

The reason I like the ZF option is their experience in large scale machinery synchronization (drill rig positioning systems etc).
Their deal with Beneteau ( a two year exclusive) appears to be leveraging their large scale control algorithms to the small scale pleasure boat range.

[mark_morwood]

Originally Posted by Catalysis

I appreciate all the advice on getting tuition on handling a cat. In my case I have many years (30+) sailing experience including the last 2 years owning a large cat.

i.e. I can spin (or is it twirl) my cat at will.

However what I'm considering is a technology experiment that will allow precision control of a large cat (hold a fixed spot, move with precision to another spot - the dock etc ) so that singled handed people (who may be aging but don't want to quit)have the option of retrofitting fixed plane saildrives with GPS controlled rotating drives.

I fully realize that there are trade offs (cost, complexity etc.) but believe that the positives are also worth evaluating. The technology is rapidly changing and NMEA 2000 based systems offer options that just weren't available a few years ago.

One of the great features of this forum is the breadth of diverse opinions and I appreciate suggestions that may help move the project forward.

Paul

Paul,

As one of the people who gave you advice you didn't really need because I didn't realize your background, sorry about that. Sounds like an interesting research project and it will be cool to hear how it turns out if you go ahead. Personally I don't think it makes a lot of sense in general for the average catamaran user today, but certainly sounds like you understand the pros and cons of what you are trying, and the rest of us will be happy to learn from your experience.

Regards,
Mark.

[Catalysis]

Thanks Mark - I have (or rather used to have) an industrial process automation background and am interested in bringing some of the large scale technology advances (such as ship/oil rig precision positioning technologies) to the recreational boating scale.

The Canmet and NMEA 2000 communications bus technology coupled with electronic engine and emerging new swivel saildrive systems offer many options that were way too expensive for the private sailor.

I'll let the forum know how my research proceeds.

Paul

[Danthefisherman]

Hi Paul,

How's the project coming along? I found this forum by accident while looking up an idea for a commercial fishing vessel. You're definitely on to something here and nobody gets it! A displacement power cat with 12-15:1 hulls using pod drives would be a great multi purpose, one man commercial fishing vessel. I'd like a boat for inshore snapper lining here in NZ that cruised at 16 knots+ using very little fuel so I am able to unload a small, high value catch every day, direct to restaurants. Using pod drives and having the boat stay in one spot with hands off would be a huge advantage while hauling lines and nets. There is even potential for jigging and drop lining between the hulls while covered by a shelter deck in rough conditions that stop most boats from working

[Lagoon4us]

Originally Posted by sandy daugherty

As I read the comments here, what you are asking is possible, and the majority are asking why you would want to.
Two engines on a catamaran do greatly enhance maneuverablilty, but do not provide a means for powering beamwise, athwartship, or sideways (depending on your preference of terms.)

This is desirable in a number of common situations: sliding into a narrow space in adverse breezes or current, joining a circle raft while letting an anchor rode out, or just holding a position at a dock while tying up single handed. And there are accepted practices for doing all the above using great skill and competent crew.

I have toyed with the idea of mounting midship outboards on diagonal "transoms" and turning one or both to thrust laterally, or z pods on a larger cat. If you think about it a while, and recall some mishaps with confused crew, you might get to like the idea.

Contrary to some opinions we have a Swing Arm Thruster mounted Stb side on our 440.
The third dimension of manoeuvrability is incredible.

In the Med we 98% of the time have to moor stern to, usually a quay or very overcrowded marina berth. Winds here can be quite strong and the surrounding boats usually expensive.

I have driven all types of boats over the years and i gotta agree with you, to be able to move sideways, to be able to drop an engine and still be safe is a godsend. Love the Thruster, it was fitted by the original owner, i doubted the need for it but now we love the security of knowing it's armed and ready to use at the worst time.

Cheers

[Hammer]

Originally Posted by Lagoon4us

Contrary to some opinions we have a Swing Arm Thruster mounted Stb side on our 440....

Do you have a photo of your setup?

I've never owned a catamaran (looking for my first one now), but have always wondered why Beneteau’s "Dock & Go" system weren't available as an option for the Lagoons.

For those not familiar with Beneteau’s “Dock & Go”, it uses a single joystick to manoeuver the boat. Rotate it on its axis or go sideways etc. I’ve always been told that it’s not needed due to the dual engine setup of catamarans.

It's good to know I'm not alone on this one. I'll be keen to look into bow thrusters once I get my cat. Since I usually single hand, I hope it’ll make docking much easier.

[Lagoon4us]

Originally Posted by Hammer

Do you have a photo of your setup?

I've never owned a catamaran (looking for my first one now), but have always wondered why Beneteau’s "Dock & Go" system weren't available as an option for the Lagoons.

For those not familiar with Beneteau’s “Dock & Go”, it uses a single joystick to manoeuver the boat. Rotate it on its axis or go sideways etc. I’ve always been told that it’s not needed due to the dual engine setup of catamarans.

It's good to know I'm not alone on this one. I'll be keen to look into bow thrusters once I get my cat. Since I usually single hand, I hope it’ll make docking much easier.

This picture we took during summer shows the bow-thruster swung down and ready, normally it is raised and presents a smooth hull.

Detractors that haven't experienced them will tell you there's no need however they are fantastic back up in tight spots, engine down situations.

We are moving our inside helm to be out at port quarter along with an extra joystick for thruster, this lets me or Vivien back up and throw the line and tie off without running around single handed.

Safe and effective. Cheers

[Lagoon4us]

Originally Posted by Danthefisherman

Hi Paul,

How's the project coming along? I found this forum by accident while looking up an idea for a commercial fishing vessel. You're definitely on to something here and nobody gets it! A displacement power cat with 12-15:1 hulls using pod drives would be a great multi purpose, one man commercial fishing vessel. I'd like a boat for inshore snapper lining here in NZ that cruised at 16 knots+ using very little fuel so I am able to unload a small, high value catch every day, direct to restaurants. Using pod drives and having the boat stay in one spot with hands off would be a huge advantage while hauling lines and nets. There is even potential for jigging and drop lining between the hulls while covered by a shelter deck in rough conditions that stop most boats from working

That's true, but this retro fit is on a weight sensitive sailing catamaran, might be an issue methinks.

[Lagoon4us]

Paul i've been involved building ships/boats of all sizes and understand your idea.

Could you not simplify by linking electronic shifters to the two engines along with two thrusters back to a single joystick using the existing technology.

By delicate albeit MANUAL use of our gear/throttles and our bow thruster we can hold station very well however it is a balance with wind and tide. Using multiple GPS positions but interconnecting would imitate the commercial systems, interesting stuff!

[daysgoneby]

It's been four years since these rotating drives came out and yet they still are not readily available for single drive boats as far as I can tell, a part from getting your hands on a pair I don't believe the software has been developed for twin applications.
That said I like the idea.