Considering switching from sail to mobo.

Garold

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It's winter and I definitely have too much time to ponder.... so I was wondering about our boating.

In contrast to the last couple of seasons, we had a good summer of touring in our 40 foot Lagoon catamaran.

We had lots of great solent weekends, and had a summer cruise across to Channel Islands followed by a successful trip to the West Country and, after many years of trying, made it to the Isles of Scilly.

But we only really sailed for about 10% of the trips (best sail was across to Alderney) and otherwise we motored at an average of about 6.5 knots. And Scilly is about 250 miles from Southampton. So, in daylight hours, about 4 days, most of which we motored (calling at some nice places on the way).

So, I was thinking. If we motor so much, often because the wind is wrong strength or direction, maybe we should make the switch to full time motoring. And with that, increase the average journey speeds to perhaps 20 knots.

But having looked at the seemingly average 1mpg (compared to our boats average when motoring at 80% revs of 5-6 mpg) or thereabouts for something like a Princess 42, I'm a bit concerned about getting into something that will just drain me dry. And will I be able to sell the motorboat if the switch doesn't suit us?

Several other things attract us to motor boating including the better finished cabinetry, easier to find berthing (compared to a catamaran), and not having to handle sails (sail handling can get hairy out at sea and ain't getting easier as we get older).

So, anyone else made the switch? And what about the costs? We probably spent about £1000 to £1500 on fuel this year. I guess that would be about x5 or 6 if we were in say a 40 footish motorboat with say 350-450hp engines.

We currently have x2 40hp engines but the great thing about small engines is that they can only consume limited amounts of fuel even flat out. But we max out at about 7 knots.

Mickey takers who wish to laugh at the truth of sailors who motor a lot, be gentle. Not many sailors admit to motoring, but most sailboat owners that I know who have regular jobs/businesses and do actually get out and about, motor a lot more than they admit! You'd never get around the Channel in limited work holidays otherwise.

Just considering options at the minute but any opinions welcome.

And if anyone has a 3-4 mpg option let me know!

Cheers

Garold

Ps. At the moment, something like a low hours 3-4 year old Princess 42 looks like a suitable motorboat for our needs. Mostly only the wife and I, so big enough with occasional guests. Fast enough to shorten journey times. Good for all year round UK boating. Big enough to do North France, Channel Isles, West Country. Good brand for fixing and future value.
 
The only boats that can cruise at 15kts/ 3-4mpg are displacement Powercats.
This low drag design from Roger Hill, a respected designer from down-under in NZ, uses twin 60hp leanburn engines.
just big enough to cruise on at 33', maybe for a few weeks at a time?

A Suzuki 60hp leanburn will do 4000 revs 2/gal.hr.....
4000 revs/15kts/4gal/ looks right on the money.


click on the Magazine articles on the site to read more:
http://www.powercatsnz.com/public/index.cfm?fuseaction=app.showdesign&ID=162

View attachment 36389

Remember: 1mpg costs €700 for every 100 nm. (Handy if you're already a multi-millioraire)
 
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You're not comparing like with like. If your motored a Princess 42 at 6kts, I have no doubt it would achieve 4-5mpg which would be comparable with your cat. A Princess 42 is only guzzling fuel at 1mpg when it's doing 20kts or faster, a speed which your cat is not capable of achieving. There is no getting away from the fact that speed costs fuel whatever boat you choose. If you're happy motoring at sub planing speeds ie less than 8-9kts, then you should be looking at different types of boats, possibly a full displacement boat such as a Dutch steel cruiser of which there are many different makes or, perhaps better for sea use, a semi displacement cruiser from the likes of Aquastar, Dale Nelson, Grand Banks, Mainship, Corvette and the Elling that Nigelpickin has linked, to name just a few. A semi displacement cruiser should be more comfortable at displacement speeds than a planing boat like the P42 but has the capability to achieve moderate planing speeds in the 15-25kt range, depending on model. Just be aware that they generally guzzle even more fuel at planing speeds than planing boats.
Also worth looking at the Scandi makes like Botnia Targa, Minor, Nimbus etc who produce sound practical boats albeit which are mainly out and out planing hulls
 
You're not comparing like with like. If your motored a Princess 42 at 6kts, I have no doubt it would achieve 4-5mpg which would be comparable with your cat. A Princess 42 is only guzzling fuel at 1mpg when it's doing 20kts or faster, a speed which your cat is not capable of achieving. There is no getting away from the fact that speed costs fuel whatever boat you choose. If you're happy motoring at sub planing speeds ie less than 8-9kts, then you should be looking at different types of boats, possibly a full displacement boat such as a Dutch steel cruiser of which there are many different makes or, perhaps better for sea use, a semi displacement cruiser from the likes of Aquastar, Dale Nelson, Grand Banks, Mainship, Corvette and the Elling that Nigelpickin has linked, to name just a few. A semi displacement cruiser should be more comfortable at displacement speeds than a planing boat like the P42 but has the capability to achieve moderate planing speeds in the 15-25kt range, depending on model. Just be aware that they generally guzzle even more fuel at planing speeds than planing boats.
Also worth looking at the Scandi makes like Botnia Targa, Minor, Nimbus etc who produce sound practical boats albeit which are mainly out and out planing hulls

Thanks for the ideas so far.

However Mike, I think that I probably confused things whilst rambling earlier. I was only comparing where I am now to where I may be if we make the change. I recognise that there are pros and cons.

However, to be clear, I'd like to travel faster than 6-7 knots (ideally around 20 knots) (don't really need to blast around, just to get places quicker). And after some reflection of this summer, we currently mainly motored the whole summer long in our sail boat. So perhaps I should consider a motor boat anyway. But I'm coming from sailing, so the leap from sailing boat mpg to motorboat mpg is a bit of a concern.

In fact I have redone my figures and I think now that I probably travel a lot of the time at high engine revs so my cat probably does more like 4mpg (given that we have two engines, a genny, and two heating boilers, I have never earnestly calculated the pure consumption figures for propulsion). So perhaps the transition to a mobo won't be as big a jump as I believe.

Many years ago we once had a displacement motor boat, and it wouldn't be something that I would choose again.

Cheers

Garold

Ps The Elling 3 is interesting (never thought about a single engined boat), as is the Greenline 40 (they do 20 knots with one of the engine options).
 
Ps The Elling 3 is interesting (never thought about a single engined boat), as is the Greenline 40 (they do 20 knots with one of the engine options).[/QUOTE]

The Elling is lovely, hope they are making them in 10 years or so when we plan to slow down and do the Great Loop....
 
However, to be clear, I'd like to travel faster than 6-7 knots (ideally around 20 knots) (don't really need to blast around, just to get places quicker). And after some reflection of this summer, we currently mainly motored the whole summer long in our sail boat. So perhaps I should consider a motor boat anyway. But I'm coming from sailing, so the leap from sailing boat mpg to motorboat mpg is a bit of a concern.
Any 40ft motorboat is likely to be consuming fuel at 1-1.5mpg at 20kts so I don't think there's any way around the fact that if you want to travel faster, you going to burn more fuel. The Greenline hybrid is an interesting concept which has been cleverly marketed but the electric motor is only going to be propelling the boat at very low speeds and then only for a short distance. At 20kts, the diesel engine is going to be driving the boat all the time and then you're just lugging around a few hundred kilos of useless electric motor and batteries. IMHO, the Greenline hybrid version is better suited to inland waterways. On it's own merits and without the hybrid system, however, the Greenline looks like a nice boat
 
Many years ago we once had a displacement motor boat, and it wouldn't be something that I would choose again.
May I ask you why? Just curious, 'cause it's much more common to find boaters used to planing boats wishing to move towards displacement, rather than the other way round.
Anyhow, if you're already used to catamarans and to their jerky sea motion, powercats are definitely more efficient than anything else, both at slow and fast speed.
 
May I ask you why? Just curious, 'cause it's much more common to find boaters used to planing boats wishing to move towards displacement, rather than the other way round.
Anyhow, if you're already used to catamarans and to their jerky sea motion, powercats are definitely more efficient than anything else, both at slow and fast speed.

My experience of a displacement speed trawler yacht was not dissimilar to motoring in the catamaran. Steady but tedious 6-8 knots. No speed to catch a short weather sindow. Not enough speed to ignore the tidal currents. And still several days of motoring to get to or back from anywhere that we may wish to visit in the summer breaks.

I think that slow speed has comfort and money saving merit for longer journeys. But at the moment, I'm thinking that we are short on time (work etc) and so I may have to pay the price to go faster. If we want to go say from Solent down to Dartmouth we need to string together two reasonable weather days in a slow boat. Whereas I was hoping to reduce this to one with a faster boat. Though we made the Scillies this year, it is the fourth time that we have attempted it, always failed before by not having a long enough weather window(s) to make it down and back.

Also, long and slow sea journeys are not something that I enjoy. I have done them over many years but I'm still working on the best diet to fight off seasickness. I recognise that this is specific to me and slower journeys are fine for some.

We moved over to catamarans about 5-6 years ago because my wife didn't like the heeling of a normal sailing monohull. The change was right for us at that time. However I think that if we make a change to a mobo, I don't want to go to a powercat. I'd like to go to a more conventional mainstream mobo. Easier berthing too etc.

Garold
 
Don't dismiss the 10 mtr range of boats, approx. 2mpg instead of 1mpg in the 40' size range.

The Hardy 32 is very nice, and keeps it's value well.
twin 250's/ 9gal/2500rev/ 15kts..........nearly 2 mpg if you slow down a tad.

View attachment 36395
 
My experience of a displacement speed trawler yacht was not dissimilar to motoring in the catamaran. Steady but tedious 6-8 knots. No speed to catch a short weather sindow. Not enough speed to ignore the tidal currents. And still several days of motoring to get to or back from anywhere that we may wish to visit in the summer breaks.
Another consideration with displacement type trawlers like, for example, Nordhavns, is that they are very heavy and drag a lot of hull through the water so actually they're not very economical at displacement speed as a result. A Princess 42 is going to be a lot more economical than a Nordhavn 43 at 6kts but then of course, you wouldn't want to be out in a real blow in the Princess
 
I think that slow speed has comfort and money saving merit for longer journeys.
But at the moment, I'm thinking that we are short on time (work etc) and so I may have to pay the price to go faster.
Yep, that pretty much rules out slow boating.
Though I disagree (sort of) with the idea that the slow speed merits are only relevant for longer journeys.
Imho, they are true regardless of how much time you're spending out there.
And for really long journeys, there's no such thing as a pleasure boat which is fast enough, anyway... :)
 
We moved over to catamarans about 5-6 years ago because my wife didn't like the heeling of a normal sailing monohull. The change was right for us at that time. However I think that if we make a change to a mobo, I don't want to go to a powercat. I'd like to go to a more conventional mainstream mobo. Easier berthing too etc.

Garold

Just a thought, but on our way up to our 40 ft, we had a "wife doesn't like" reason for change, and I suppose it begs the question whether yours would like the change in "ride" from your Cat at 6-7 knots to a Mobo at 20 - 25 Kts ?.

If you are not sure would it be worth Chartering one for a day and doing a reasonable passage ? That way you could see if you (she) like it as the costs involved in selling, buying, using it and deciding you aren't too keen after all, selling and trying again could render the fuel costs quite small ?

I cant comment on whether the passages you are considering would be better with a single or twin engine set up, I'll leave that to the more experienced members but please keep us posted as your thoughts ... and the winter, unfolds...
 
Another consideration with displacement type trawlers like, for example, Nordhavns, is that they are very heavy and drag a lot of hull through the water so actually they're not very economical at displacement speed as a result. A Princess 42 is going to be a lot more economical than a Nordhavn 43 at 6kts but then of course, you wouldn't want to be out in a real blow in the Princess

Funny thing is that these days, I usually go to sea armed with about 3 weather forecasts and so we are less likely than ever to get caught out. I know that one can always get it wrong, but 30 years ago in the trawler yacht, all we had was the met office forecasts on R4 (and we did get caught out in rotten weather much more often).

As for the Nordhavn, I really enjoy the whole ethos of the brand. However, I don't think that my mainly weekend-cruising is what these boats are best suited.

Thinking about it, a boat that suits all of our sailing requirements probably doesn't exist. A boat that is best to shoot down to Yarmouth for a short weekend probably isn't best suited to the annual trip around various Channel destinations.

But I suppose I still have to look for the best compromise, because I think that we have it not-quite-right at the minute.

Rusty, thanks for pointing out the Hardy option. I think that semi disp speed and seaworthiness may be an option. Or are they economical just because they are smaller?

Cheers

G
 
Any 40ft motorboat is likely to be consuming fuel at 1-1.5mpg at 20kts so I don't think there's any way around the fact that if you want to travel faster, you going to burn more fuel. The Greenline hybrid is an interesting concept which has been cleverly marketed but the electric motor is only going to be propelling the boat at very low speeds and then only for a short distance. At 20kts, the diesel engine is going to be driving the boat all the time and then you're just lugging around a few hundred kilos of useless electric motor and batteries. IMHO, the Greenline hybrid version is better suited to inland waterways. On it's own merits and without the hybrid system, however, the Greenline looks like a nice boat

Yes, I think that the Greenline 40 looks like nice accom for the weekend.

And the solar panels would help to keep juice in the batteries.

And their super slippery hull design sounds like it would be generally economical.

But I can't think where the hybrid function would help me. And it must have a cost in the price of the boat.

I'd be more interested too if it came without the hybrid drive system, though I do like the fact that it already seems to be set up for constant 240v supply already.

G
 
Broom 42cl perhaps?

+1

I was wondering the same. If used to sailing then economic cruising at 16-18kt will seem fast enough for time constrained passage making. The layout may better suit the damp cooler climate in these isles, and internally the 42CL will have 35% more usable living space than a P42, and no other 42ft FB can come close to the master cabin space. But the 42CL layout does not suit warmer climates. But you get the best of both worlds, three clips, then press a switch and the enclosed cockpit becomes a sunny flybridge.
 
Just a thought, but on our way up to our 40 ft, we had a "wife doesn't like" reason for change, and I suppose it begs the question whether yours would like the change in "ride" from your Cat at 6-7 knots to a Mobo at 20 - 25 Kts ?.

If you are not sure would it be worth Chartering one for a day and doing a reasonable passage ? That way you could see if you (she) like it as the costs involved in selling, buying, using it and deciding you aren't too keen after all, selling and trying again could render the fuel costs quite small ?

I cant comment on whether the passages you are considering would be better with a single or twin engine set up, I'll leave that to the more experienced members but please keep us posted as your thoughts ... and the winter, unfolds...

Yes. Good idea.

I think I need to experience the motion of a planing 40 footer.

But just at the moment I am exploring all the possible options before I make the next step to charter days, test sails etc.

I do know that I've thought about his as much as I can on my own.

G
 

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