need your experience heads.....

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swqa1234

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OK so here goes....I'm a total newbie and looking for advice. I have no idea if what I am about to say is complete left field or achievable but I am looking to bounce ideas off your more seasoned and knowledgeable experience......i have sailed on a schooner and raced 21ft and 26ft power boats

Idea
purchase a boat to "sail" around....wherever I can. wife and 2 teenage boys - and me!

Plan A
50 - 60 foot Fairline Sqn 2 x 680hp MAN engines (yes I have something in mind)

years 1 and 2 - motor round Med to get used to boat and for fam to enjoy
years 2/3 upwards - time to venture out

I am thinking to cut down on fuel costs i will cruise around 8kn (whats the rush). In my mind I also will run on 1 engine at a time for 3 to 4 hours and then switch over to save engine hours.

My thoughts are this would work out around 10ltrs per hour

Plan B
Do it in a sail Beneteau Cyclades 43.4

I would really welcome your thoughts :)
 
Plan B No contest - but there is a huge choice of boats in that size range so if you have not yet bought suggest you look at a variety of boats before deciding.
 
With two teenagers, you'll want three cabins, two heads and as many socialising areas as possible.

One engine at a time is probably not necessary, it's easy to obsess about keeping hours down but you will probably find that you do less than you currently expect.

If you are really wanting a 10knt cruising speed then I would avoid going for something that will do 30kts; you'll just end up putting the throttle down all the time!

So a 50' mobo that's economical to run might make an elling e4 worth a look. And it the kind of boat that's perfect for a couple once the teen monsters have grown out of you.

Of course it comes down to budget and with the sailing choice coming in at 100k for a good recent one then that might make the decision easier.

Good luck
 
I manage 9 knots at 800 rpm ( tick over is 600 ) -uses 27 L / hr with both running .Similiar 12.8 L MAN ,s
I think one will use more net as you will have to rev it up more and it will have the drag of t,other to cope with .
Also in N I suspect the dead engine,s prop will " wind up " the G box .

So I think you may need to rethink your maths

A or B ?
It all depends on what you are prepared to spend on fuel / annum -how far you want to travel .
I,am about to start my 11th year MoBo ing in the med and there has been some season,s where it's been pretty calm ie min wind .
This means the sailboats too are all motoring .
 
yep fuel will be more than you estimate. I have fuel flow guages on my boat. I tried running slowly at one engine at a time and compared it to using both engines together. total fuel consumption pretty much the same. If you get a planing boat you will end up planing its too tempting. If you are happy going a long way slowly, sailing boats do it really well. - have a look at a moody 45......
 
Forget one engine running. I tried it on my first boat.

a. it does not run straight

b. you will loose something powered by that engine ( power steering in my case)

c. you might damage the gearbox

d. you save no fuel anyways so the whole exercise is pointless.


Someone here do slow pooling but planing boats are not really meant for this. Those that do it tend to have stabilisers so the ride is flat and smooth.

I do it from time to time for maybe an hour but that is all i can take to be honest.

Fuel won't be 10 lph

Squadron 65 with 2 x CAT 1150

9.5 kts is 950 RPM = 20 lt per engine - 40 total

If of interest

13 kts 1200 rpm 85 lph per engine
16.5 kts 1600 rpm 121 lph per engine
22 kts 1800 rpm 150 lph per engine
24.5 kts 1900 rpm159 lph per engine
26.5 kts 2000 rpm 167 lph per engine
30 kts 2200 rpm 189 lph per engine

I have run a WOT but not bothered to write it down its about 230 lph per engine
 
swqa1234 said:
I am thinking to cut down on fuel costs i will cruise around 8kn (whats the rush).

I would really welcome your thoughts :)
Click to expand...

It will be like driving a Lamborghini around in 1st gear..... only more painful.

You will also be doing the engines no world of harm.... they will not be at operating temperature... the oil will be the wrong viscosity... the turbos / head / exhaust will coke up.... the batteries will not charge.....

The ride will be less than ideal.... a planing boat is not designed as a slow cruiser... its designed to plane!!!!

By all means get a big mobo, but if you want to take the gentle option.... and why not? Then look at trawler yachts and other styles of displacement boats. Lots of space for your money.

Before embarking on a long voyage under sail, its worth trying it out with the teenagers... some may love it.... I did, but there is a lot to not like about it for your average teen.


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Edit:
Woah!!! 1200 posts.. do I get a badge or something???
 
Plan B but I would look at Hanse instead of Beneteau. Another alternative would be a Catamaran. I'd look at a Lagoon 440.
 
Portofino said:
I manage 9 knots at 800 rpm ( tick over is 600 ) -uses 27 L / hr with both running. Similiar 12.8 L MAN ,s
Click to expand...
That's not bad at all. You've got the V8 version, don't you?
I'm asking because I only recently understood that most MAN engines (V8/V10/V12) run on just half of their cylinders, up to 1000rpm or so.
But before you ask, I don't know if running them for long with just half of the cylinders actually "working" can create any problem.
 
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jrudge said:
13 kts 1200 rpm 85 lph per engine
16.5 kts 1600 rpm 121 lph per engine
22 kts 1800 rpm 150 lph per engine
24.5 kts 1900 rpm159 lph per engine
26.5 kts 2000 rpm 167 lph per engine
30 kts 2200 rpm 189 lph per engine
Click to expand...
J, I'm a bit surprised by those numbers, because actual consumption curve (liter per Nm, rather than hour) looks a bit too flat.
Even decreasing, actually: burning 1 l/Nm MORE at 22kts than at 30kts sounds weird.
Assuming that your boat is steadily on the plane at 22kts, but I'm sure she is...?
 
I forgot to say, re. the OP question:
Plan A and B are both feasible, I reckon. But the actual experience is very different.
If you are not interested in sailing, imho it's pointless to risk to hit your head against the boom at all times while you are onboard.
Otoh, if you are, MoBos are obviously not an option.
Horses for courses springs to mind...
 
MapisM said:
J, I'm a bit surprised by those numbers, because actual consumption curve (liter per Nm, rather than hour) looks a bit too flat.
Even decreasing, actually: burning 1 l/Nm MORE at 22kts than at 30kts sounds weird.
Assuming that your boat is steadily on the plane at 22kts, but I'm sure she is...?
Click to expand...

They Are very flat. I run real time nm per litre and tend to run at 29 kts if the sea allows as is it more economical


The flow rates are accurate as the totalisers and the tank fill volume are the same as near as.

I
 
MapisM said:
I forgot to say, re. the OP question:
Plan A and B are both feasible, I reckon. But the actual experience is very different.
If you are not interested in sailing, imho it's pointless to risk to hit your head against the boom at all times while you are onboard.
Otoh, if you are, MoBos are obviously not an option.
Horses for courses springs to mind...
Click to expand...

I don't think you have to be in one camp or the other. Both have their pros and cons.
 
MapisM said:
That's not bad at all. You've got the V8 version, don't you?
I'm asking because I only recently understood that most MAN engines (V8/V10/V12) run on just half of their cylinders, up to 1000rpm or so.
But before you ask, I don't know if running them for long with just half of the cylinders actually "working" can create any problem.
Click to expand...
We have the 2876 straight 6
Tend to Pootle to keep cool get fresh air /breeze when it's stinking hot ie above 30 Air and 26 sea temp ,watching the world go buy .
 
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shan said:
I don't think you have to be in one camp or the other. Both have their pros and cons.
Click to expand...
My point exactly.
When I said that the experience is very different, I didn't want to dismiss sailboats - far from that!
I actually love sailing... Particularly when someone else takes care of the flappy bits!
 
MapisM said:
My point exactly.
When I said that the experience is very different, I didn't want to dismiss sailboats - far from that!
I actually love sailing... Particularly when someone else takes care of the flappy bits!
Click to expand...

One of the reasons I suggested a Hanse as opposed to Beneteau is because of the self tacking jib and as there is no clutter on the deck. Everything leads back to the cockpit making it an easy boat to sail. Of course, catamarans are even easier and have the benefit of loads of social areas. More like a floating apartment than a boat!
 
thx for the reply. Elling was interesting and I hadn't heard of one before however just out my price range. nice boat tho...
 
thx for that info. interesting fuel consumption even with 2 running. I must admit I hadn't thought about the GBox issue naively thinking the prop would spin freely so that's some more info for me too. I know what you mean re sail having to motor tho
see you out there :)
 
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