kjell
05-01-2006, 10:11 AM
I like to have a 100/100 motorsailor not a 50/50 motorsailor.
What is the difference?
What is the difference?
View Full Version : 50/50 or 100/100.
Windvang
05-01-2006, 10:44 AM
Hullshape, windage and weight on the sailing side.
Hullshape ,drag of keel, rig and large rudder on motor side.
Hullshape ,drag of keel, rig and large rudder on motor side.
SeaSpark
05-01-2006, 10:46 AM
50% + 50% = 100% = 1 boat
100%+100% = 200% the answer to this calulation implies you need two boats.
100%+100% = 200% the answer to this calulation implies you need two boats.
Vega
05-01-2006, 11:28 AM
I like to have a 100/100 motorsailor ....
What is the difference?
Welcome to the club. I want one of those two, but windvang is right, a 100/100 is impossible.
For the old style (traditional) motorsailors I would say : 70 (motor)/30(sail).
For the new concept I would say: 50/50 to 85/75 in all possible combinations.
I am trying to design a 95/50:p
What is the difference?
Welcome to the club. I want one of those two, but windvang is right, a 100/100 is impossible.
For the old style (traditional) motorsailors I would say : 70 (motor)/30(sail).
For the new concept I would say: 50/50 to 85/75 in all possible combinations.
I am trying to design a 95/50:p
Vega
05-01-2006, 11:36 AM
50% + 50% = 100% = 1 boat
100%+100% = 200% the answer to this calulation implies you need two boats.
All interpretations are possible but with 95/50 what I want to say is that such a boat only lose 5% in performance to a fast dedicated sailboat and lose about 50% in efficiency to a pure dedicated motorboat.:D
100%+100% = 200% the answer to this calulation implies you need two boats.
All interpretations are possible but with 95/50 what I want to say is that such a boat only lose 5% in performance to a fast dedicated sailboat and lose about 50% in efficiency to a pure dedicated motorboat.:D
marshmat
05-01-2006, 02:33 PM
There was a really good suggestion (at least I thought so) somewhere in an earlier thread to list motorsailers by SA/D and HP/D ratios, ie. a 14/14. If I remember I'll add the link to the thread... I think that's a much more informative system, especially when comparing not-quite-so-similar boats.
kjell
05-01-2006, 03:19 PM
50% + 50% = 100% = 1 boat
100%+100% = 200% the answer to this calulation implies you need two boats.
A Motorsailer is a displacement hull and limited to the hull speed.
With existing modern sail system and powerful lightweight engines.
If I can reach hull speed under sail, with the engine/s stopped for me it is a 100% sailing boat.
If I can reach hull speed running the engine/s without sail/s , for me it is a 100% motor boat.
100%+100% = 200% the answer to this calulation implies you need two boats.
A Motorsailer is a displacement hull and limited to the hull speed.
With existing modern sail system and powerful lightweight engines.
If I can reach hull speed under sail, with the engine/s stopped for me it is a 100% sailing boat.
If I can reach hull speed running the engine/s without sail/s , for me it is a 100% motor boat.
Guillermo
05-01-2006, 04:46 PM
There was a really good suggestion (at least I thought so) somewhere in an earlier thread to list motorsailers by SA/D and HP/D ratios, ie. a 14/14. If I remember I'll add the link to the thread... I think that's a much more informative system, especially when comparing not-quite-so-similar boats.
Thanks Marshmat. That's my proposed labeling system. SA/D ratio I use is the standard and well known one. For the HP/D ratio I use 6*HP*1000/D, because I've found this matches quite well to compare it with the SA/D ratio (Imperial units)
The benefit of this labeling system, against the "century" rule, is that saying that a boat is a 50/50 motorsailer says nothing about the real sail and engine power of the boat, nor if she's light or heavy, while this new label I propose does. And most of the times this rule derives in the talking about 90/90, 100/100, etc., as it is based in personal perception and opinions, and not in real figures.
Here (again, as it was already posted in the thread marshmat mentions) an explanation of my 'short' labeling system for monohull sailing boats:
Example label: H 14/14
First figure relates to the SA/D ratio (to the closest integer), so to the sailing power, and
Second figure relates to the 6*HP*1000/D coeficient (to the closest integer), so to the motoring power
Letter is related to the D/L ratio, as follows (monohulls):
VL = Very low D/L ratio, under 100
L= Low D/L, from 100 to 200, typically 150
M = Medium D/L, from 200 to 300, typically 250
H = High D/L, from 300 to 400, tipically 350
VH = Very Heavy D/L, over 400
So, a sailing boat (monohull) with a D/L ratio of 356, an SA/D ratio of 14.45 and an HP/D ratio of 2.3, would have a label like: H -14/14
- If ratio in label is greater than one, the boat is sailing oriented. If less than one, motoring oriented.
Applying it to a motorsailers definition:
- If first figure is 14+ the boat has plenty of power under sails alone. Lower than 10 seems too low sails power to me for a motorsailer: The boat should rather be considered a "sail assisted motor boat". Definitively if under 8. If higher than 16 the boat should probably be better classificated as a sailing boat having more or less engine power.
- Second figure (motor) being over 18 means quite an excess of engine power, in my opinion. A figure under 9 will indicate the boat is a sailing boat with auxiliary engine, rather than a motorsailer. For an efficient motorsailer, it should be around 14, let's say from 12 to 16.
- What are called 50/50 motorsailers by the "century" rule (Or 90/90 or whatever you want), become 14/14 (more or less) under this labeling system.
That's the basic thing. We can also add some letters at the end of it, to better explain the intended design (Or marketing!) concept, as MS for Motorsailers, PH for Pilot House, RS for raised saloon, OC for ocean cruiser, CC for coastal cruiser, etc, etc.
So, if we read something like M 16/12 RSOC, we can understand the boat is a "medium weight, sail oriented, raised saloon ocean cruiser" most probably with a good performance under sail and with an engine allowing for economic motoring passages but having yet enough power reserve to beat to winward in a gale in protected waters.
Going further, we can try to look for how to better enphasize and define some subtle but most important differences like the ones between boats labeled as M 14/14 CCPH and M 14/14 OCPH. To this end, and using what's already available in the industry, we can add the UE Category Design letter (A, B, C, D) which in a very precise way defines the designed weather-coping ability. So we arrive to the very precise (maybe to precise to be easily remembered):
'Labeling System'
Example: M A16/12 PHMS
We labeled here a real ocean going, medium weighted, sails-only oriented, nicely powered, pilothouse motorsailer. A whole lot of a definition. And a whole lot of a boat.
For those not familiarized with the UE Design Category, here you have the meanings:
- A, applies to boats designed to cope with winds in excess of force 8 and waves over 4 m (significative height). Oceanic.
- B, to boats designed to cope with winds up to force 8 and waves up to 4 m. Short open seas passages.
- C, to boats designed to cope with winds up to force 6 and 2 m waves. Coastal sailing.
- D, to boats designed to navigate in protected waters, maximum force 4 and 0,5 m waves.
If some of you are interested in knowing more, plase visit the pages:
http://www.xente.mundo-r.com/motorsailers/index.htm
Thanks Marshmat. That's my proposed labeling system. SA/D ratio I use is the standard and well known one. For the HP/D ratio I use 6*HP*1000/D, because I've found this matches quite well to compare it with the SA/D ratio (Imperial units)
The benefit of this labeling system, against the "century" rule, is that saying that a boat is a 50/50 motorsailer says nothing about the real sail and engine power of the boat, nor if she's light or heavy, while this new label I propose does. And most of the times this rule derives in the talking about 90/90, 100/100, etc., as it is based in personal perception and opinions, and not in real figures.
Here (again, as it was already posted in the thread marshmat mentions) an explanation of my 'short' labeling system for monohull sailing boats:
Example label: H 14/14
First figure relates to the SA/D ratio (to the closest integer), so to the sailing power, and
Second figure relates to the 6*HP*1000/D coeficient (to the closest integer), so to the motoring power
Letter is related to the D/L ratio, as follows (monohulls):
VL = Very low D/L ratio, under 100
L= Low D/L, from 100 to 200, typically 150
M = Medium D/L, from 200 to 300, typically 250
H = High D/L, from 300 to 400, tipically 350
VH = Very Heavy D/L, over 400
So, a sailing boat (monohull) with a D/L ratio of 356, an SA/D ratio of 14.45 and an HP/D ratio of 2.3, would have a label like: H -14/14
- If ratio in label is greater than one, the boat is sailing oriented. If less than one, motoring oriented.
Applying it to a motorsailers definition:
- If first figure is 14+ the boat has plenty of power under sails alone. Lower than 10 seems too low sails power to me for a motorsailer: The boat should rather be considered a "sail assisted motor boat". Definitively if under 8. If higher than 16 the boat should probably be better classificated as a sailing boat having more or less engine power.
- Second figure (motor) being over 18 means quite an excess of engine power, in my opinion. A figure under 9 will indicate the boat is a sailing boat with auxiliary engine, rather than a motorsailer. For an efficient motorsailer, it should be around 14, let's say from 12 to 16.
- What are called 50/50 motorsailers by the "century" rule (Or 90/90 or whatever you want), become 14/14 (more or less) under this labeling system.
That's the basic thing. We can also add some letters at the end of it, to better explain the intended design (Or marketing!) concept, as MS for Motorsailers, PH for Pilot House, RS for raised saloon, OC for ocean cruiser, CC for coastal cruiser, etc, etc.
So, if we read something like M 16/12 RSOC, we can understand the boat is a "medium weight, sail oriented, raised saloon ocean cruiser" most probably with a good performance under sail and with an engine allowing for economic motoring passages but having yet enough power reserve to beat to winward in a gale in protected waters.
Going further, we can try to look for how to better enphasize and define some subtle but most important differences like the ones between boats labeled as M 14/14 CCPH and M 14/14 OCPH. To this end, and using what's already available in the industry, we can add the UE Category Design letter (A, B, C, D) which in a very precise way defines the designed weather-coping ability. So we arrive to the very precise (maybe to precise to be easily remembered):
'Labeling System'
Example: M A16/12 PHMS
We labeled here a real ocean going, medium weighted, sails-only oriented, nicely powered, pilothouse motorsailer. A whole lot of a definition. And a whole lot of a boat.
For those not familiarized with the UE Design Category, here you have the meanings:
- A, applies to boats designed to cope with winds in excess of force 8 and waves over 4 m (significative height). Oceanic.
- B, to boats designed to cope with winds up to force 8 and waves up to 4 m. Short open seas passages.
- C, to boats designed to cope with winds up to force 6 and 2 m waves. Coastal sailing.
- D, to boats designed to navigate in protected waters, maximum force 4 and 0,5 m waves.
If some of you are interested in knowing more, plase visit the pages:
http://www.xente.mundo-r.com/motorsailers/index.htm
FAST FRED
05-03-2006, 06:48 AM
On a good sailboat with a proper engine & sailing prop installed , the ONLY thing you loose is for the WEIGHT of all the installed machinery and equippment & fuel carried.
Deduct 10% from 100% sail for the weight.
On a motorboat the only disadvantage is the extra windage lost due to the rigging , and the internal space lost for sails.
Deduct 10% from a good displacement motorboat.
Result a 90/90 can easily be envisioned .
FAST FRED
Deduct 10% from 100% sail for the weight.
On a motorboat the only disadvantage is the extra windage lost due to the rigging , and the internal space lost for sails.
Deduct 10% from a good displacement motorboat.
Result a 90/90 can easily be envisioned .
FAST FRED
kjell
05-03-2006, 07:46 AM
On a good sailboat with a proper engine & sailing prop installed , the ONLY thing you loose is for the WEIGHT of all the installed machinery and equippment & fuel carried.
Deduct 10% from 100% sail for the weight.
On a motorboat the only disadvantage is the extra windage lost due to the rigging , and the internal space lost for sails.
Deduct 10% from a good displacement motorboat.
Result a 90/90 can easily be envisioned .
FAST FRED
Why don’t add 10% on the sail area and 10% on the engine power and you have the 100/100.
Deduct 10% from 100% sail for the weight.
On a motorboat the only disadvantage is the extra windage lost due to the rigging , and the internal space lost for sails.
Deduct 10% from a good displacement motorboat.
Result a 90/90 can easily be envisioned .
FAST FRED
Why don’t add 10% on the sail area and 10% on the engine power and you have the 100/100.
Raggi_Thor
05-03-2006, 07:57 AM
Why don’t add 10% on the sail area and 10% on the engine power and you have the 100/100.
If you remove the engine you can have more ballast and then you can add more sail.
If you install a bigger engine you have to remove more ballast and then you have to remove more sail.
If you remove the engine you can have more ballast and then you can add more sail.
If you install a bigger engine you have to remove more ballast and then you have to remove more sail.
kjell
05-03-2006, 08:06 AM
If you remove the engine you can have more ballast and then you can add more sail.
If you install a bigger engine you have to remove more ballast and then you have to remove more sail.
If you remove the engine it will not be a motorsailer.
A more powerfully engine doesn’t mean more weight.
If you install a bigger engine you have to remove more ballast and then you have to remove more sail.
If you remove the engine it will not be a motorsailer.
A more powerfully engine doesn’t mean more weight.
Raggi_Thor
05-03-2006, 08:24 AM
OK, you can have a modern lightweight engine, but if you want a 120HP diesel that's probably 400kg(?) while a 30HP is more like 100kg(?).
Most diesels burn 0.2kg or so per hour per hp, so you need more fuel for the bigger engine.
I think you can get a good 90/90 with light displacement, lightweight engine and maybe a lifting keel.
Most diesels burn 0.2kg or so per hour per hp, so you need more fuel for the bigger engine.
I think you can get a good 90/90 with light displacement, lightweight engine and maybe a lifting keel.
Vega
05-03-2006, 07:41 PM
On a good sailboat with a proper engine & sailing prop installed , the ONLY thing you loose is for the WEIGHT of all the installed machinery and equippment & fuel carried.
Deduct 10% from 100% sail for the weight.
On a motorboat the only disadvantage is the extra windage lost due to the rigging , and the internal space lost for sails.
Deduct 10% from a good displacement motorboat.
Result a 90/90 can easily be envisioned .
FAST FRED
I agree on the first 90%, for sail ability, but for having the same capability of a motorboat I would say that you had to have the power to make 3/4 of hull speed in a moderate gale (40 knots of wind on the head, and 4 to 5 M waves). I don't know for sure, but I suppose that in a 10 ton, 42 foot motor boat, for doing that you will need something like 150hp.
If you put that engine weight in a sailboat you can say goodbye to the 90% sail ability.
I would rather maintain the 90% of sail ability with a 50% motor ability, that would be ( in the same moderate gale situation), the ability to make a little bit more than half of the hull speed, and for that I guess that something like 75hp is enough.
That’s why I think that a 90/90 is, or impossible, or very difficult to get (maybe not so difficult in big sail boats).
Deduct 10% from 100% sail for the weight.
On a motorboat the only disadvantage is the extra windage lost due to the rigging , and the internal space lost for sails.
Deduct 10% from a good displacement motorboat.
Result a 90/90 can easily be envisioned .
FAST FRED
I agree on the first 90%, for sail ability, but for having the same capability of a motorboat I would say that you had to have the power to make 3/4 of hull speed in a moderate gale (40 knots of wind on the head, and 4 to 5 M waves). I don't know for sure, but I suppose that in a 10 ton, 42 foot motor boat, for doing that you will need something like 150hp.
If you put that engine weight in a sailboat you can say goodbye to the 90% sail ability.
I would rather maintain the 90% of sail ability with a 50% motor ability, that would be ( in the same moderate gale situation), the ability to make a little bit more than half of the hull speed, and for that I guess that something like 75hp is enough.
That’s why I think that a 90/90 is, or impossible, or very difficult to get (maybe not so difficult in big sail boats).
Guillermo
05-04-2006, 12:44 AM
I agree on the first 90%, for sail ability, but for having the same capability of a motorboat I would say that you had to have the power to make 3/4 of hull speed in a moderate gale (40 knots of wind on the head, and 4 to 5 M waves). I don't know for sure, but I suppose that in a 10 ton, 42 foot motor boat, for doing that you will need something like 150hp....
I think your engine should allow you to deal (motoring alone) with gale force head winds in sheltered waters, not open seas with 4-5 m waves. Maybe that's too much and, with a fixed propeller you'd have to slow down rpm just not to overload the engine if you have to motor for a long time. So probably 150 HP for a 42' 10 ton boat is much more than needed.
As an example, Victorie 12.70 (http://www.victoire.nl/schepen.php?boot=7) mounts a 55 HP engine, which gives her an 6*HP/D ratio of 16.62 which is, in my opinion, good enough. And that boat has an SA/D ratio of 15.27, so probably a nice performer under sail too.
When in a gale in open waters, if you have to motor, you'd probably will not try to go directly into the wind, but motorsail into it at an open angle with the proper set of sails. That's wiser and that's what motorsailers are good for.
Cheers.
I think your engine should allow you to deal (motoring alone) with gale force head winds in sheltered waters, not open seas with 4-5 m waves. Maybe that's too much and, with a fixed propeller you'd have to slow down rpm just not to overload the engine if you have to motor for a long time. So probably 150 HP for a 42' 10 ton boat is much more than needed.
As an example, Victorie 12.70 (http://www.victoire.nl/schepen.php?boot=7) mounts a 55 HP engine, which gives her an 6*HP/D ratio of 16.62 which is, in my opinion, good enough. And that boat has an SA/D ratio of 15.27, so probably a nice performer under sail too.
When in a gale in open waters, if you have to motor, you'd probably will not try to go directly into the wind, but motorsail into it at an open angle with the proper set of sails. That's wiser and that's what motorsailers are good for.
Cheers.
Vega
05-04-2006, 06:06 AM
I think your engine should allow you to deal (motoring alone) with gale force head winds in sheltered waters, not open seas with 4-5 m waves. Maybe that's too much and, with a fixed propeller you'd have to slow down rpm just not to overload the engine if you have to motor for a long time. So probably 150 HP for a 42' 10 ton boat is much more than needed.
When in a gale in open waters, if you have to motor, you'd probably will not try to go directly into the wind, but motorsail into it at an open angle with the proper set of sails. That's wiser and that's what motorsailers are good for.
Cheers.
I am not talking of motoring directly into the wind, but at a reasonably close angle. Remember I am talking about pure motorboats, and that when you will need the extra power (safety power) of your motor, it will not be in sheltered waters.
And if you can safely (but uncomfortably) motor home, that is right ahead in the wind, say at 15 miles, why should you turn around and motor more conformably to a 30 mile port that it is not your own?
A motor boat should have some advantages over a motorsailor, don’t you think?
Seriously, Guillermo, you could contribute a lot to this discussion. Can you see what is the power that fisherman have there in a boat like the one we are talking about? I don't mean trawlers, but the ones that need engine not to pull nets, only to move the boat.
Those are the guys with real experience in what kind of power a motorboat needs to maximize safety.
When in a gale in open waters, if you have to motor, you'd probably will not try to go directly into the wind, but motorsail into it at an open angle with the proper set of sails. That's wiser and that's what motorsailers are good for.
Cheers.
I am not talking of motoring directly into the wind, but at a reasonably close angle. Remember I am talking about pure motorboats, and that when you will need the extra power (safety power) of your motor, it will not be in sheltered waters.
And if you can safely (but uncomfortably) motor home, that is right ahead in the wind, say at 15 miles, why should you turn around and motor more conformably to a 30 mile port that it is not your own?
A motor boat should have some advantages over a motorsailor, don’t you think?
Seriously, Guillermo, you could contribute a lot to this discussion. Can you see what is the power that fisherman have there in a boat like the one we are talking about? I don't mean trawlers, but the ones that need engine not to pull nets, only to move the boat.
Those are the guys with real experience in what kind of power a motorboat needs to maximize safety.
FAST FRED
05-04-2006, 06:21 AM
If you do the math , the windage at 50K for most boats isnt that high, and the usual reserve of engine power most boats have will handle it.
The problem of besting 12 to 20 ft waves is more a matter of accepting a slower speed of advance. A VP prop would be a big help , as it would in the pure sail mode.
The biggest hassle with requiring extreme amounts of thrust is the size and cost of the large diameter prop required to do this effictivly.The deeper reduction gear costs about the same , although the $haft dia will be larger.
Of course this is a 1 time cost and the added efficency of a huge slow turning prop will lower fuel consumption while motoring or MS , might actually pay over the long term..
FAST FRED
The problem of besting 12 to 20 ft waves is more a matter of accepting a slower speed of advance. A VP prop would be a big help , as it would in the pure sail mode.
The biggest hassle with requiring extreme amounts of thrust is the size and cost of the large diameter prop required to do this effictivly.The deeper reduction gear costs about the same , although the $haft dia will be larger.
Of course this is a 1 time cost and the added efficency of a huge slow turning prop will lower fuel consumption while motoring or MS , might actually pay over the long term..
FAST FRED
gonzo
05-04-2006, 09:21 AM
Sailboats have no motors. With a motor installed, it is either an auxiliary or a motorsailor. The boundary is rather subjective. The percentage for the sailing part assumes a high performance sailor without the drag of a propeller, underwater openings, shafts, etc. The motorboat assumes a performance motorboat that is at least semidisplacement.
Vega
05-04-2006, 11:55 AM
Sailboats have no motors. With a motor installed, it is either an auxiliary or a motorsailor. .
It is rather funny to call to all high performance offshore racing sailboats "auxiliaries". That’s what they are, according to you.:p
It is rather funny to call to all high performance offshore racing sailboats "auxiliaries". That’s what they are, according to you.:p
Guillermo
05-04-2006, 12:26 PM
..Can you see what is the power that fisherman have there in a boat like the one we are talking about? I don't mean trawlers, but the ones that need engine not to pull nets, only to move the boat...
Good question. Unluckily fishing vessels owners nowadays (Well, yesterday, because nowadays they become to be worried with fuel costs) are (were) not really worried about fuel costs and they tend to overpower vessels, maximizing cargo, crew accomodation (this last not always) and fishing equipment, forgetting about hydrodynamics, fuel efficiency and the like :( . This trend has produced what I understand as cramped ugly vessels (but very efficient predators of the seas). Even today, with all the worrying, what they really ask for is not more efficent propulsion systems, but cheaper fuels :rolleyes:
So it's better to go back in time and see what happened several decades ago, with boats like the 50' LOA Irish fishing boat I posted in the Trollers vs Trawlers discussion (Was that one?). She mounted an 88 HP, 750 rpm diesel engine, moving a 32" x 19" three bladed propeller. The boat moved at 9 knots at the designed waterline load condition. Displacement: 28.9 tonnes. Consume: 18.2 l/h.
Mmmm....I'm realizing I have a lot of info on old fishing boats from the world around, and maybe some day I will take the time to do some statistical work.
Cheers.
Good question. Unluckily fishing vessels owners nowadays (Well, yesterday, because nowadays they become to be worried with fuel costs) are (were) not really worried about fuel costs and they tend to overpower vessels, maximizing cargo, crew accomodation (this last not always) and fishing equipment, forgetting about hydrodynamics, fuel efficiency and the like :( . This trend has produced what I understand as cramped ugly vessels (but very efficient predators of the seas). Even today, with all the worrying, what they really ask for is not more efficent propulsion systems, but cheaper fuels :rolleyes:
So it's better to go back in time and see what happened several decades ago, with boats like the 50' LOA Irish fishing boat I posted in the Trollers vs Trawlers discussion (Was that one?). She mounted an 88 HP, 750 rpm diesel engine, moving a 32" x 19" three bladed propeller. The boat moved at 9 knots at the designed waterline load condition. Displacement: 28.9 tonnes. Consume: 18.2 l/h.
Mmmm....I'm realizing I have a lot of info on old fishing boats from the world around, and maybe some day I will take the time to do some statistical work.
Cheers.
gonzo
05-04-2006, 12:27 PM
That is the definition of auxiliary. I didn't make it up.
Vega
05-04-2006, 02:41 PM
Good question. Unluckily fishing vessels owners nowadays not really worried about fuel costs and they tend to overpower vessels, maximizing cargo, crew accomodation ...So it's better to go back in time and see what happened several decades ago, with boats like the 50' LOA Irish fishing boat I posted in the Trollers vs Trawlers discussion (Was that one?). She mounted an 88 HP, 750 rpm diesel engine, moving a 32" x 19" three bladed propeller. The boat moved at 9 knots at the designed waterline load condition. Displacement: 28.9 tonnes. Consume: 18.2 l/h.
.
Well I agree, but lets look at what they used to have 20 years ago and not at what they used when they did not have the choice to do otherwise.
That Irish boat looks like a boat built in the 50's or beginning of 60's. I bet that if they had the technology (small engines) and the money (economic situation) they would have put a more powerful motor in that boat.
Of course if you chose to have a look at the engines that the fishing boats of the same size carried in the 30's, you are going to find 35hp engines.
So let's not exaggerate and perhaps look at the motors that they used 20 years ago?
.
Well I agree, but lets look at what they used to have 20 years ago and not at what they used when they did not have the choice to do otherwise.
That Irish boat looks like a boat built in the 50's or beginning of 60's. I bet that if they had the technology (small engines) and the money (economic situation) they would have put a more powerful motor in that boat.
Of course if you chose to have a look at the engines that the fishing boats of the same size carried in the 30's, you are going to find 35hp engines.
So let's not exaggerate and perhaps look at the motors that they used 20 years ago?
Guillermo
05-04-2006, 04:43 PM
..So let's not exaggerate and perhaps look at the motors that they used 20 years ago?
That's an idea, but there are other ways, as estimating power with some well known formulas used for fishing boats design.
Also we can do something even simpler:
The Irish boat (Disp = 28.9 ton; Lwl = 46' 8") is using 3 HP/ton, which was accepted as a nice power for sailing boats 30 years ago. For efficient motorsailers nowadays my opinion is that we should move around 5 HP/ton, bringing in the Irish case power to 144.5 HP. In my opinion sailing boats with HP/Disp < 3 should always be classified as 'Auxiliaries', as discussed before. Between 3 and 4 let's say there is the 'subjective' zone gonzo talks about.
My simple formula to estimate power (posted in 'Motorsailers' thread), HP = K * Lwl * (Lwl - 10), although out of range here (works more or less accurately only between 20'<Lwl<40'), using K=0.1 for a heavyweight like this Irish boat, gives a power of 171.14 HP, so almost 6 HP/ton, which is somewhat high. In my opinion efficient motorsailers should have a power between 4.5 < HP/Disp < 5.5. Let's say we can accept from 4 to 6, depending on appliances aboard, etc. In the last times there's has been even a tendency to overpower, clearly ultrapassing 6, with the showing up of semiplanning or even planning motorsailers (!)
(Note: I've analized 85 motorsailers, with Lwl between 24' to 60')
That's an idea, but there are other ways, as estimating power with some well known formulas used for fishing boats design.
Also we can do something even simpler:
The Irish boat (Disp = 28.9 ton; Lwl = 46' 8") is using 3 HP/ton, which was accepted as a nice power for sailing boats 30 years ago. For efficient motorsailers nowadays my opinion is that we should move around 5 HP/ton, bringing in the Irish case power to 144.5 HP. In my opinion sailing boats with HP/Disp < 3 should always be classified as 'Auxiliaries', as discussed before. Between 3 and 4 let's say there is the 'subjective' zone gonzo talks about.
My simple formula to estimate power (posted in 'Motorsailers' thread), HP = K * Lwl * (Lwl - 10), although out of range here (works more or less accurately only between 20'<Lwl<40'), using K=0.1 for a heavyweight like this Irish boat, gives a power of 171.14 HP, so almost 6 HP/ton, which is somewhat high. In my opinion efficient motorsailers should have a power between 4.5 < HP/Disp < 5.5. Let's say we can accept from 4 to 6, depending on appliances aboard, etc. In the last times there's has been even a tendency to overpower, clearly ultrapassing 6, with the showing up of semiplanning or even planning motorsailers (!)
(Note: I've analized 85 motorsailers, with Lwl between 24' to 60')
safewalrus
05-04-2006, 04:47 PM
Whats in a definition? so sailboats with engines are either auxilaries or motorsailors eh! why not call ALL sailboats with engines 'motorsailors' or all motorboats with sails 'sailormotors'. Does a 'drifter' with a steadying sail make it a 'sailing' drifter (I don't think so)! Even today a lot of Danish boats operate like this! Or to be more obtuse, is the old HMS Warrior (1860 vintage) three masted sailing war ship with a single propellor and a big engine room/boiler room and a crew in excess of 600! classed as a 'motorsailor' - technically yes! 'Motorsailor is not really a sensible definition is it?
Unfortunately the numbers game played by some tends to confuse the majority! Also why go back 20 years (according to my reckoning thats not the 50's or 60's) are we looking at boats now or is this about history - and if it's about history lets get back to the correct use and definition of words as used then!:rolleyes:
Unfortunately the numbers game played by some tends to confuse the majority! Also why go back 20 years (according to my reckoning thats not the 50's or 60's) are we looking at boats now or is this about history - and if it's about history lets get back to the correct use and definition of words as used then!:rolleyes:
gonzo
05-05-2006, 08:02 AM
The term motorsailor was a marketing ploy. The salespeople claim you could get the best of both world without any drawbacks. However, sailboat and powerboat are easy to define.
FAST FRED
05-07-2006, 06:14 AM
"The term motorsailor was a marketing ploy.
Yet Herrishoff described his offshore fast cruiser , the Marco Polo , long befire Madison Ave created thew usual add blither.
For folks looking for fast passage times the Marco Polo should be the starting benchmark.
At 55ft she was designed to maintain 10K in offshore cruising using power with sails.
Today the engine would have more reliability and weigh 1/10 of the old iron monster and with backyard skills cored GRP hull construction the hull could weigh 1/4 of the origonal.
The pointy stern would have to go for better speeds and sea keeping , and of course the intereior and layout are archaic by todays standards .
But the M/P was a fine sea boat from folks that have had the pleasure of a ride.
A modern version of this concept would be a DELIGHT!
FAST FRED
Yet Herrishoff described his offshore fast cruiser , the Marco Polo , long befire Madison Ave created thew usual add blither.
For folks looking for fast passage times the Marco Polo should be the starting benchmark.
At 55ft she was designed to maintain 10K in offshore cruising using power with sails.
Today the engine would have more reliability and weigh 1/10 of the old iron monster and with backyard skills cored GRP hull construction the hull could weigh 1/4 of the origonal.
The pointy stern would have to go for better speeds and sea keeping , and of course the intereior and layout are archaic by todays standards .
But the M/P was a fine sea boat from folks that have had the pleasure of a ride.
A modern version of this concept would be a DELIGHT!
FAST FRED
yipster
05-07-2006, 12:53 PM
http://www.tennantdesign.co.nz/pics/plans/SOUNDERMS1.jpg
100/100 say 80/80 is two boats indeed, look at Malcolm Tennants motorsailers (http://www.tennantdesign.co.nz/boatdesigns/95/Sounder%20-%2046MS.htm)and a dedicated retractable propulsion nowadays shouldnt be that difficult i figger :confused:
100/100 say 80/80 is two boats indeed, look at Malcolm Tennants motorsailers (http://www.tennantdesign.co.nz/boatdesigns/95/Sounder%20-%2046MS.htm)and a dedicated retractable propulsion nowadays shouldnt be that difficult i figger :confused:
Tad
05-07-2006, 01:29 PM
Marketing ploy? Madison Avenue?
Yacht Designers, like everyone else in business, have been forever inventing quasi-technical terms to delineate their work from that of others. I am lead to believe that the term Motorsailer was coined by some unknown yacht designer trying to feed his kids.
They were originally referred to as 50-50's, but this inferred less than great performance in either mode. This term was used by William Hand to describe his design , Nor'Easter, launched in 1927. The motorsailor term seems to have appeared in 28 or 29, as Hand's Bluebill of 28 and John G. Hanna's Centaur of 29 are both referred to (in various publications) as Motorsailers.
In the early 1930's Rudder magazine ran an article entitled "The Case for the Motorsailor". I was a collection of remarkes by five prominent designers of the time. The designers were, Gordon Munro, Bill Hand, Walter McInnis, Thomas Bowes, and John Hanna. In it Hanna states, "The motorsailor goes back to fisherman origin. Though reluctant to adopt the engine, once they did the fishermen were quick to increase to full power, and they saw they might as well cut down rigs to heavy weather size, as it did not pay to fool with sail at all in light weather.....William H. Hand was the first designer to produce motorsailors in sufficient numbers to establish a distinct yacht type."
Some designers totaly rejected the Motorsailor term. Philip Rhodes produced Tamaris in 1938 and insisted that she was not a motorsailor but a "Full-powered Sailer". Francis Herreshoff would not use the term, calling Marco Polo and her forbearers Ocean Cruisers or Auxiliary Ketches.
All the best, Tad
Yacht Designers, like everyone else in business, have been forever inventing quasi-technical terms to delineate their work from that of others. I am lead to believe that the term Motorsailer was coined by some unknown yacht designer trying to feed his kids.
They were originally referred to as 50-50's, but this inferred less than great performance in either mode. This term was used by William Hand to describe his design , Nor'Easter, launched in 1927. The motorsailor term seems to have appeared in 28 or 29, as Hand's Bluebill of 28 and John G. Hanna's Centaur of 29 are both referred to (in various publications) as Motorsailers.
In the early 1930's Rudder magazine ran an article entitled "The Case for the Motorsailor". I was a collection of remarkes by five prominent designers of the time. The designers were, Gordon Munro, Bill Hand, Walter McInnis, Thomas Bowes, and John Hanna. In it Hanna states, "The motorsailor goes back to fisherman origin. Though reluctant to adopt the engine, once they did the fishermen were quick to increase to full power, and they saw they might as well cut down rigs to heavy weather size, as it did not pay to fool with sail at all in light weather.....William H. Hand was the first designer to produce motorsailors in sufficient numbers to establish a distinct yacht type."
Some designers totaly rejected the Motorsailor term. Philip Rhodes produced Tamaris in 1938 and insisted that she was not a motorsailor but a "Full-powered Sailer". Francis Herreshoff would not use the term, calling Marco Polo and her forbearers Ocean Cruisers or Auxiliary Ketches.
All the best, Tad
Guillermo
05-07-2006, 04:30 PM
Very interesting post, Tad. Do you know how to get a copy of "The Case for the motorsailor" article?
"....Hanna states, "The motorsailor goes back to fisherman origin. Though reluctant to adopt the engine, once they did the fishermen were quick to increase to full power, and they saw they might as well cut down rigs to heavy weather size, as it did not pay to fool with sail at all in light weather....."
This confirms the origin of the motorsailer concept as a motor boat with auxiliary sails, bred in fishing boats. As a matter of fact it happens to be what the term evokes to most of the people.
Herreshoff and Rhodes reluctancy to use the term is well present still nowadays, as many boatbuilders/designers do not want their boats being subliminally labeled in people's minds as heavy, slow & bulky old fogeys.
But nowadays there are beautiful examples of 'Teenys' (Motorsailers with both figures in my labeling system in the 13-16 range), like the Noordkapper 40 or the Perry 45. Nothing to be ashame of.
"....Hanna states, "The motorsailor goes back to fisherman origin. Though reluctant to adopt the engine, once they did the fishermen were quick to increase to full power, and they saw they might as well cut down rigs to heavy weather size, as it did not pay to fool with sail at all in light weather....."
This confirms the origin of the motorsailer concept as a motor boat with auxiliary sails, bred in fishing boats. As a matter of fact it happens to be what the term evokes to most of the people.
Herreshoff and Rhodes reluctancy to use the term is well present still nowadays, as many boatbuilders/designers do not want their boats being subliminally labeled in people's minds as heavy, slow & bulky old fogeys.
But nowadays there are beautiful examples of 'Teenys' (Motorsailers with both figures in my labeling system in the 13-16 range), like the Noordkapper 40 or the Perry 45. Nothing to be ashame of.
gonzo
05-08-2006, 01:13 AM
Fasr Fred: I don't think "any with backyard skills cored GRP hull construction the hull could weigh 1/4 of the origonal." Do you know the displacement as designed? Wood construction, by Herreshoff's rules is of moderate weight and great strength. I can't see how low quality sandwich construction can compete. Also, it wouldn't be a Herreshoff. He strongly emphazised that he would never allow one of his boats to be built out of "frozen snot"
FAST FRED
05-08-2006, 06:02 AM
"I can't see how low quality sandwich construction can compete. Also, it wouldn't be a Herreshoff. He strongly emphazised that he would never allow one of his boats to be built out of "frozen snot""
Hand layup of a proper engineered foam core is hardly "low quality sandwich construction " after all Franz Mass built a reputation on going racing in his plug built hand layup sail boats.
No if building with 4x6 timber in 12 inch centers and 1 1/2 inch planking is needed to be a "real" Herrishoff , a frozen snot variant would not be OK.
And gasoline Sterlings are hard to find parts for, these days.
But if the design concept , how to cross oceans with tiny crew , little fuss , and advance at 240 miles a day is used as a goal for a more modern boat , the IDEAS in the Marco Polo are of use.
A 55ft hull of 3/4 inch Airex and built to OCEAN standards will come in at 3 lbs per sq ft.
About the same as 1 inch mahog hull , sans ribs backbone ect .
This is with 3/4 oz matt and 24oz woven roving on the topsides , inside & out.
The extra internal layer of 3/4 mat adds little extra weight but creates a finished interior surface.
FAST FRED
Hand layup of a proper engineered foam core is hardly "low quality sandwich construction " after all Franz Mass built a reputation on going racing in his plug built hand layup sail boats.
No if building with 4x6 timber in 12 inch centers and 1 1/2 inch planking is needed to be a "real" Herrishoff , a frozen snot variant would not be OK.
And gasoline Sterlings are hard to find parts for, these days.
But if the design concept , how to cross oceans with tiny crew , little fuss , and advance at 240 miles a day is used as a goal for a more modern boat , the IDEAS in the Marco Polo are of use.
A 55ft hull of 3/4 inch Airex and built to OCEAN standards will come in at 3 lbs per sq ft.
About the same as 1 inch mahog hull , sans ribs backbone ect .
This is with 3/4 oz matt and 24oz woven roving on the topsides , inside & out.
The extra internal layer of 3/4 mat adds little extra weight but creates a finished interior surface.
FAST FRED
brian eiland
05-15-2006, 01:28 AM
The term motorsailor was a marketing ploy. The salespeople claim you could get the best of both world without any drawbacks.
A Motorsailer is a displacement hull and limited to the hull speed
I don't agree that a motorsailer needs to be a displacement vessel. And I don't think the term was a marketing ploy.
I'm also not real enthused that we need to pin down some technical forumla to define a motorsailer....gets overly complicated. Rather I feel the term may have simply come about to define a vessel whose intentions it was to be utilized in both sailing and powering modes....unlike a sailing vessel that might employ an auxillary engine for docking or no wind....or a power vessel that makes no pretentions of utilizing sail power.
So the motorsailer is very definitely its own type of vessel. But as I've written before, we don't hear much of motorsailers these days. They're not a popular subject. Traditional motorsailers have always been such a compromise, they have fallen into disfavor in the market, and in the boating literature. The term has even had negative connotations for several decades now. (as Tad said, even some designers rejected the term).
On the contrary, I embrace the term. Should not today's boats be faster and better with new materials, light marine diesels, and better shapes? Should not this be the sensible alternative, the common sense move up from the beloved family sailboat? When trawler options are discussed, suggestions of boredom arise. A lifetime of sail would be discarded, and what happens when the motor quits? Well, hopefully it won't quit, but one can always sail home in a boat with sails on it. For truly long-range cruising and/or remote exploration, the motorsailer can outshine both the sailing aux and the trawler types.
We need to modernize the motorsailer. The multihull plan-form holds great promises to improve this breed. The long slender hulls of the catamaran type vessel have proven themselves to be real efficient to push under both power & sail. And not only are they efficient, but they can be pushed beyond the traditional hull-length/speed limitations. Just what the modern motorsailer needs, a far less compromising increase in both their sail & power performance, while maintaining an economy of operation that allows truly long range capability.
In light airs, running one engine often is all that is needed to bring the apparent wind forward to make the sails work harder, and the combination provides much better results than either motoring or sailing alone……
.sailing synergy/harmony, the motor taking over in the lulls and the rig taking over in the puffs.
more? http://boatdesign.net/forums/showpost.php?p=43251&postcount=25
A Motorsailer is a displacement hull and limited to the hull speed
I don't agree that a motorsailer needs to be a displacement vessel. And I don't think the term was a marketing ploy.
I'm also not real enthused that we need to pin down some technical forumla to define a motorsailer....gets overly complicated. Rather I feel the term may have simply come about to define a vessel whose intentions it was to be utilized in both sailing and powering modes....unlike a sailing vessel that might employ an auxillary engine for docking or no wind....or a power vessel that makes no pretentions of utilizing sail power.
So the motorsailer is very definitely its own type of vessel. But as I've written before, we don't hear much of motorsailers these days. They're not a popular subject. Traditional motorsailers have always been such a compromise, they have fallen into disfavor in the market, and in the boating literature. The term has even had negative connotations for several decades now. (as Tad said, even some designers rejected the term).
On the contrary, I embrace the term. Should not today's boats be faster and better with new materials, light marine diesels, and better shapes? Should not this be the sensible alternative, the common sense move up from the beloved family sailboat? When trawler options are discussed, suggestions of boredom arise. A lifetime of sail would be discarded, and what happens when the motor quits? Well, hopefully it won't quit, but one can always sail home in a boat with sails on it. For truly long-range cruising and/or remote exploration, the motorsailer can outshine both the sailing aux and the trawler types.
We need to modernize the motorsailer. The multihull plan-form holds great promises to improve this breed. The long slender hulls of the catamaran type vessel have proven themselves to be real efficient to push under both power & sail. And not only are they efficient, but they can be pushed beyond the traditional hull-length/speed limitations. Just what the modern motorsailer needs, a far less compromising increase in both their sail & power performance, while maintaining an economy of operation that allows truly long range capability.
In light airs, running one engine often is all that is needed to bring the apparent wind forward to make the sails work harder, and the combination provides much better results than either motoring or sailing alone……
.sailing synergy/harmony, the motor taking over in the lulls and the rig taking over in the puffs.
more? http://boatdesign.net/forums/showpost.php?p=43251&postcount=25
FAST FRED
05-15-2006, 06:17 AM
The only problem being the fact that CATAMIRANS CAPSIZE ,
so their ability to ocean cruise is merly a roll of the dice , before the "big one" turns the boat turtle.
Recent NASA data claims the number of LARGE waves is very underestimated world wide , as the commercial boats travel only in limited sea lanes, and don't get to see the BIG ONES.
Cruisers usually avoid the "low power steam" routes and will be more exposed than the ESSO MARU.
Traveling "in season" will reduce the risks , but its only time before the righting gear will be needed.
A trimiran can have a better chance at offshore self recovery , but lacks the 4 bedroom apartments with ballroom some "need" to cruise with.
A self righting monohull would be the classic choice , but getting todays accomidation into a hull 6 or 8X as long as it is wide would be the chalenge.
I believe if cruisers can accept the accomidations of a 40 ft'er in a 65 or 70 ft SKINNY boat the 10K+ 10mpg+ M/S cruiser could be done.
AS the weight would be close to the 40ft M/S , the cost to construct would be similar.
Any designs for that?
FAST FRED
so their ability to ocean cruise is merly a roll of the dice , before the "big one" turns the boat turtle.
Recent NASA data claims the number of LARGE waves is very underestimated world wide , as the commercial boats travel only in limited sea lanes, and don't get to see the BIG ONES.
Cruisers usually avoid the "low power steam" routes and will be more exposed than the ESSO MARU.
Traveling "in season" will reduce the risks , but its only time before the righting gear will be needed.
A trimiran can have a better chance at offshore self recovery , but lacks the 4 bedroom apartments with ballroom some "need" to cruise with.
A self righting monohull would be the classic choice , but getting todays accomidation into a hull 6 or 8X as long as it is wide would be the chalenge.
I believe if cruisers can accept the accomidations of a 40 ft'er in a 65 or 70 ft SKINNY boat the 10K+ 10mpg+ M/S cruiser could be done.
AS the weight would be close to the 40ft M/S , the cost to construct would be similar.
Any designs for that?
FAST FRED
yipster
05-15-2006, 08:44 AM
Any designs for that?
FAST FRED
http://www.morozov-yachts.com/index.php?catalog=156
think i still favor the bigger cat tho...
as you said "righting" may be an design challange
and when a mono rolls you may even get wetter
where did i read bout masttop cushions....
FAST FRED
http://www.morozov-yachts.com/index.php?catalog=156
think i still favor the bigger cat tho...
as you said "righting" may be an design challange
and when a mono rolls you may even get wetter
where did i read bout masttop cushions....
Raggi_Thor
05-15-2006, 08:47 AM
Something like this? or ist it too fat?
http://www.sailmagazine.com/boatreviews/Convergence/
http://www.wyliecat.com/yachts/models/wyliecat_65.html
Seems like it does 11 knots with a 100HP Yanmar.
http://www.sailmagazine.com/boatreviews/Convergence/
http://www.wyliecat.com/yachts/models/wyliecat_65.html
Seems like it does 11 knots with a 100HP Yanmar.
brian eiland
05-15-2006, 08:52 AM
The only problem being the fact that CATAMIRANS CAPSIZE ,so their ability to ocean cruise is merly a roll of the dice , before the "big one" turns the boat turtle.
By that definition then no power boat should go to sea as they can rolled over rather easy, and don't self-right.
A trimiran can have a better chance at offshore self recovery
How do you arrive at that conclusion?
By that definition then no power boat should go to sea as they can rolled over rather easy, and don't self-right.
A trimiran can have a better chance at offshore self recovery
How do you arrive at that conclusion?
yipster
05-15-2006, 08:58 AM
http://www.wyliecat.com/yachts/models/wyliecat_65.html
Seems like it does 11 knots with a 100HP Yanmar.
good articles Raggi but why is the wiliecat a mono :confused:
Seems like it does 11 knots with a 100HP Yanmar.
good articles Raggi but why is the wiliecat a mono :confused:
Vega
05-15-2006, 09:30 AM
I don't agree that a motorsailer needs to be a displacement vessel. And I don't think the term was a marketing ploy.
I'm also not real enthused that we need to pin down some technical forumla to define a motorsailer....gets overly complicated. Rather I feel the term may have simply come about to define a vessel whose intentions it was to be utilized in both sailing and powering modes....unlike a sailing vessel that might employ an auxillary engine for docking or no wind....or a power vessel that makes no pretentions of utilizing sail power.
Brian, I agree with you about this, but the distinction between sail boat and motor sailor that you have made is not clear enough, at least for me.
When you say that a sailboat is a “vessel that might employ an auxiliary engine for docking or no wind....” well, a Motor sailor as well. If you say that a sailboat has an engine that is used mostly for docking, then you are excluding the vast majority of boars that are sold as sailboats.
Nowadays a 36ft boat is sold with an engine of around 30hp and a 40ft with an engine of about 50hp. These engines on those boats can handle almost all situations, being able to travel exclusively using its engine in most situations.
That engine is not enough only in unusual situations, in gale force winds going windward, etc.
The differences regarding a motor sailor are that this one has the extra power to handle these situations, too. I would say that for doing that, in a 36 ft will be required an engine of at least 50 hp, and in a 40ft, an engine of 75 hp.
As to cats, I agree with you in what concerns coastal crafts, but regarding passage makers, I agree with Fred. A cat without any sail can be capsized only by the pressure of the wind on the mast. Sure, it is needed a lot of wind, but in a recent ocean race, several capsized that way. For those, that had a massive RM, 70knots is enough.
70 knots of wind is not very common but I bet that several members of this forum have already encountered that. I guess they would not make it in a Cat.
Even in the Med, there are some stories of crews of big cruising cats that have been in deep trouble with 9 and 10 force winds. Out of the summer months, in some zones, the wind can blow often like that.
Of course this can be overcome if you use smaller rigs, but then the sailing performance will suffer.
There are other options: one is to consider a rig not normally used in cats, a Gaff rig with a big bowsprit; another is to use a variant of a Latin rig (Catalans have a race with traditional boats that have to use Latin rigs. It’s incredible the performance and the upgrades they have introduced in that rig). These types of rigs without sails are a lot shorter, for the same sail area, therefore they will offer a smaller resistance to the wind.
I'm also not real enthused that we need to pin down some technical forumla to define a motorsailer....gets overly complicated. Rather I feel the term may have simply come about to define a vessel whose intentions it was to be utilized in both sailing and powering modes....unlike a sailing vessel that might employ an auxillary engine for docking or no wind....or a power vessel that makes no pretentions of utilizing sail power.
Brian, I agree with you about this, but the distinction between sail boat and motor sailor that you have made is not clear enough, at least for me.
When you say that a sailboat is a “vessel that might employ an auxiliary engine for docking or no wind....” well, a Motor sailor as well. If you say that a sailboat has an engine that is used mostly for docking, then you are excluding the vast majority of boars that are sold as sailboats.
Nowadays a 36ft boat is sold with an engine of around 30hp and a 40ft with an engine of about 50hp. These engines on those boats can handle almost all situations, being able to travel exclusively using its engine in most situations.
That engine is not enough only in unusual situations, in gale force winds going windward, etc.
The differences regarding a motor sailor are that this one has the extra power to handle these situations, too. I would say that for doing that, in a 36 ft will be required an engine of at least 50 hp, and in a 40ft, an engine of 75 hp.
As to cats, I agree with you in what concerns coastal crafts, but regarding passage makers, I agree with Fred. A cat without any sail can be capsized only by the pressure of the wind on the mast. Sure, it is needed a lot of wind, but in a recent ocean race, several capsized that way. For those, that had a massive RM, 70knots is enough.
70 knots of wind is not very common but I bet that several members of this forum have already encountered that. I guess they would not make it in a Cat.
Even in the Med, there are some stories of crews of big cruising cats that have been in deep trouble with 9 and 10 force winds. Out of the summer months, in some zones, the wind can blow often like that.
Of course this can be overcome if you use smaller rigs, but then the sailing performance will suffer.
There are other options: one is to consider a rig not normally used in cats, a Gaff rig with a big bowsprit; another is to use a variant of a Latin rig (Catalans have a race with traditional boats that have to use Latin rigs. It’s incredible the performance and the upgrades they have introduced in that rig). These types of rigs without sails are a lot shorter, for the same sail area, therefore they will offer a smaller resistance to the wind.
brian eiland
05-15-2006, 10:12 AM
good articles Raggi but why is the wiliecat a mono :confused:
It's in reference to the 'cat rig' of their smaller and very popular vessel,
"The Wyliecat 30 was conceived with the premise that performance sailing doesn't need to be complicated to be fast and fun. Combining state-of-the-art technology with the time-proven cat rig...."
http://www.wyliecat.com/yachts/models/wyliecat_30.html
It's in reference to the 'cat rig' of their smaller and very popular vessel,
"The Wyliecat 30 was conceived with the premise that performance sailing doesn't need to be complicated to be fast and fun. Combining state-of-the-art technology with the time-proven cat rig...."
http://www.wyliecat.com/yachts/models/wyliecat_30.html
Vega
05-15-2006, 12:15 PM
good articles Raggi but why is the wiliecat a mono :confused:
Hello Yipster
Cat here doesn't come from Catamaran.
It comes from an American traditional type of boat, the Cat boat.
Those boats have only one sail, with the mast near the bow.
http://www.catboats.org/gallery.htm
Hello Yipster
Cat here doesn't come from Catamaran.
It comes from an American traditional type of boat, the Cat boat.
Those boats have only one sail, with the mast near the bow.
http://www.catboats.org/gallery.htm
yipster
05-15-2006, 12:22 PM
thanks guy's, i'm only a (originaly advertising) designer studying boats :cool:
brian eiland
05-15-2006, 12:36 PM
... the distinction between sail boat and motor sailor that you have made is not clear enough, at least for me.When you say that a sailboat is a “vessel that might employ an auxiliary engine for docking or no wind....”
...and additionally powering for some significant portion of journeys. Yes there are various degrees of sailing verses power and 'sailing under power'. The intention of the design is to power more than the needs of an 'auxillary' craft.
_____________________________________________________
Nowadays a 36ft boat is sold with an engine of around 30hp and a 40ft with an engine of about 50hp. These engines on those boats can handle almost all situations, being able to travel exclusively using its engine in most situations.
That engine is not enough only in unusual situations, in gale force winds going windward, etc.
Going to windward in a gale can require considerable more power than often believed. Just maintaining a heading into a seaway might need less power. Sailing craft (and their masters) should not have to be dependent on an engine in a gale.
_____________________________________________________
A cat without any sail can be capsized only by the pressure of the wind on the mast. Sure, it is needed a lot of wind, but in a recent ocean race, several capsized that way. For those, that had a massive RM, 70knots is enough.
You might note that these are primarily ocean racing vessels with very tall wing-mast. Those wing mast can present a very sizable 'sail area' by themselves, and up very high. These mast can be particularly troublesome when rotated sideways to the wind in a downwind sailing sitatuation aggravated by a sudden slowing of the vessel at the trough of a wave...watch out, pitchpole!!
_____________________________________________________
Of course this can be overcome if you use smaller rigs, but then the sailing performance will suffer.
Smaller rigs in comparision to what...the racing boats? Just use lower aspect ratio rigs....Marchaj had lots of praise for these style rigs in a cruising situation. In fact there driving power was superior to that of the hi-aspect ratio when beam-to the wind, or off the wind....most favored cruising aspect.
Besides a smaller sailed multi, even a fat one, will often outsail its similar length monohull.
____________________________________________________
There are other options: one is to consider a rig not normally used in cats, a Gaff rig with a big bowsprit; another is to use a variant of a Latin rig (Catalans have a race with traditional boats that have to use Latin rigs. It’s incredible the performance and the upgrades they have introduced in that rig). These types of rigs without sails are a lot shorter, for the same sail area, therefore they will offer a smaller resistance to the wind.
Obviously I will agree with you there, other rig options....witness my alternative rig ventures:
http://www.runningtideyachts.com/sail/ (http://www.runningtideyachts.com/sail/)
But realize what a VERY tough sell it is to the very conservative sailing market who has been told that the modern sloop rig is God!! And multihulls are still fighting old conservative beliefs.
________________________________________________
Ocean Capable?
At the end of this MotorSailing Posting (http://boatdesign.net/forums/showpost.php?p=43251&postcount=25) I repeat, "“This work (tank testing at Southampton Univ by Lock Crowther) has indicated that the well designed catamaran is remarkably safe in breaking waves up to considerable height, even when beam on, we were unable to capsize a power catamaran yacht in the largest wave which could be generated. This corresponded to a 52' wave for a catamaran of 40' beam. Scaling this down to a typical 24' beam cruising cat means she should be O.K. in a 31' breaking beam sea. An equivalent size mono-hull power boat was easily capsized by a 25' breaking sea, and in tests with conventional yachts after the Fastnet disaster, it was found that a 40' mono-hull yacht could capsized in a 12' breaking sea.” Added note:And with a mast (bare) the stability is generally improved.
____________________________________________________
Just as an aside, you might find this interesting, "Herreshoff's catamaran reasoning (http://boatdesign.net/forums/showthread.php?t=5843)"
...and additionally powering for some significant portion of journeys. Yes there are various degrees of sailing verses power and 'sailing under power'. The intention of the design is to power more than the needs of an 'auxillary' craft.
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Nowadays a 36ft boat is sold with an engine of around 30hp and a 40ft with an engine of about 50hp. These engines on those boats can handle almost all situations, being able to travel exclusively using its engine in most situations.
That engine is not enough only in unusual situations, in gale force winds going windward, etc.
Going to windward in a gale can require considerable more power than often believed. Just maintaining a heading into a seaway might need less power. Sailing craft (and their masters) should not have to be dependent on an engine in a gale.
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A cat without any sail can be capsized only by the pressure of the wind on the mast. Sure, it is needed a lot of wind, but in a recent ocean race, several capsized that way. For those, that had a massive RM, 70knots is enough.
You might note that these are primarily ocean racing vessels with very tall wing-mast. Those wing mast can present a very sizable 'sail area' by themselves, and up very high. These mast can be particularly troublesome when rotated sideways to the wind in a downwind sailing sitatuation aggravated by a sudden slowing of the vessel at the trough of a wave...watch out, pitchpole!!
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Of course this can be overcome if you use smaller rigs, but then the sailing performance will suffer.
Smaller rigs in comparision to what...the racing boats? Just use lower aspect ratio rigs....Marchaj had lots of praise for these style rigs in a cruising situation. In fact there driving power was superior to that of the hi-aspect ratio when beam-to the wind, or off the wind....most favored cruising aspect.
Besides a smaller sailed multi, even a fat one, will often outsail its similar length monohull.
____________________________________________________
There are other options: one is to consider a rig not normally used in cats, a Gaff rig with a big bowsprit; another is to use a variant of a Latin rig (Catalans have a race with traditional boats that have to use Latin rigs. It’s incredible the performance and the upgrades they have introduced in that rig). These types of rigs without sails are a lot shorter, for the same sail area, therefore they will offer a smaller resistance to the wind.
Obviously I will agree with you there, other rig options....witness my alternative rig ventures:
http://www.runningtideyachts.com/sail/ (http://www.runningtideyachts.com/sail/)
But realize what a VERY tough sell it is to the very conservative sailing market who has been told that the modern sloop rig is God!! And multihulls are still fighting old conservative beliefs.
________________________________________________
Ocean Capable?
At the end of this MotorSailing Posting (http://boatdesign.net/forums/showpost.php?p=43251&postcount=25) I repeat, "“This work (tank testing at Southampton Univ by Lock Crowther) has indicated that the well designed catamaran is remarkably safe in breaking waves up to considerable height, even when beam on, we were unable to capsize a power catamaran yacht in the largest wave which could be generated. This corresponded to a 52' wave for a catamaran of 40' beam. Scaling this down to a typical 24' beam cruising cat means she should be O.K. in a 31' breaking beam sea. An equivalent size mono-hull power boat was easily capsized by a 25' breaking sea, and in tests with conventional yachts after the Fastnet disaster, it was found that a 40' mono-hull yacht could capsized in a 12' breaking sea.” Added note:And with a mast (bare) the stability is generally improved.
____________________________________________________
Just as an aside, you might find this interesting, "Herreshoff's catamaran reasoning (http://boatdesign.net/forums/showthread.php?t=5843)"
Guillermo
05-15-2006, 12:59 PM
...We need to modernize the motorsailer. The multihull plan-form holds great promises to improve this breed. The long slender hulls of the catamaran type vessel have proven themselves to be real efficient to push under both power & sail. And not only are they efficient, but they can be pushed beyond the traditional hull-length/speed limitations. Just what the modern motorsailer needs, a far less compromising increase in both their sail & power performance, while maintaining an economy of operation that allows truly long range capability....
I've found almost all catamarans with engines, qualify as motorsailers using my 14/14 definition (You already know my pages http://www.xente.mundo-r.com/motorsailers/multihulls.htm), and I agree that is quite difficult to turn turtle a seamanshiply sailed cruising catamaran. So shall we agree with you that they are the paradigma of motorsailers nowadays? ;)
Big minus are probably high marina fees and higher initial cost.....
I've found almost all catamarans with engines, qualify as motorsailers using my 14/14 definition (You already know my pages http://www.xente.mundo-r.com/motorsailers/multihulls.htm), and I agree that is quite difficult to turn turtle a seamanshiply sailed cruising catamaran. So shall we agree with you that they are the paradigma of motorsailers nowadays? ;)
Big minus are probably high marina fees and higher initial cost.....
FAST FRED
05-15-2006, 05:46 PM
"By that definition then no power boat should go to sea as they can rolled over rather easy, and don't self-right.'
Many of the older displacement power boats have enough rudimentary balast to make them self righting, just a matter of high buck deck hardware ,good choice of ports and commercial style glass and mountings.OTS
Any motorsailor will be carring ballast and should be able to get back up right from a 180 displacement , as long as she remains intact.
Many, many sailboats have survived knockdowns with out being sunk or dismasted , so the big wave might roll her a few times , but the chance of survival would be hundreds of times the invereted forever catamaran.
AS in all lifes endeavours "you pays your money and takes your chances", but I would prefer the chance a really skinny lead sled gives to the certain problem of the upside down cat.
Most of the cats I have been on stank as ocean crossers as the performance NEVER exceded the expected hull speed of a lead sled. A 65 ft cat cruising at 8k is hardly worth the risk,cost or dock finding hassles and expense.
FAST FRED
Many of the older displacement power boats have enough rudimentary balast to make them self righting, just a matter of high buck deck hardware ,good choice of ports and commercial style glass and mountings.OTS
Any motorsailor will be carring ballast and should be able to get back up right from a 180 displacement , as long as she remains intact.
Many, many sailboats have survived knockdowns with out being sunk or dismasted , so the big wave might roll her a few times , but the chance of survival would be hundreds of times the invereted forever catamaran.
AS in all lifes endeavours "you pays your money and takes your chances", but I would prefer the chance a really skinny lead sled gives to the certain problem of the upside down cat.
Most of the cats I have been on stank as ocean crossers as the performance NEVER exceded the expected hull speed of a lead sled. A 65 ft cat cruising at 8k is hardly worth the risk,cost or dock finding hassles and expense.
FAST FRED
Raggi_Thor
05-15-2006, 07:09 PM
I think there are differences between coastal cruising and offshore, ocean crossings. How is he movement of a lightweight catamaran?
Vega
05-15-2006, 08:55 PM
I think there are differences between coastal cruising and offshore, ocean crossings. How is he movement of a lightweight catamaran?
There are no heavy weight cats. And the movement is what should be expected of a light craft that takes with the same wave twice, first one hull, then on the other, jerky motion is what you get. Not a comfortable boat in troubled waters.
Good for calm waters and for enjoying life when moored and a headache at the time of trying to find a place in a marina and when paying the bill…. prices and places:rolleyes:
Most of the cats I have been on stank as ocean crossers as the performance NEVER exceded the expected hull speed of a lead sled. A 65 ft cat cruising at 8k is hardly worth the risk,cost or dock finding hassles and expense.
FAST FRED
There is a good article about cats at sailnet, by John Kretschmer, a deliver skipper, , that has delivered all kinds of boats, including cats. What he says about the subject is interesting:
“this Fountaine-Pajot Venezia 42 maintained poise as she tracked over the Atlantic, easily coping with the six to eight-foot seas rushing between her hulls.
The Venezia's speed was a consistent seven to eight knots with an occasional low, double-digit spurt when surfing down a wave. My 20-year-old, 44-foot steel ketch could keep pace in these conditions, ....
And cats do sail flat. The lack of rolling downwind is refreshing, especially on a long trade-wind passage. Most of today's cruising cats are well-designed, engineered, and constructed.
But I have discovered compromises. It takes awhile to adjust to the lack of heel, a result of high initial stability, and the ensuing fast, jerky motion. These cats in general have a lot more motion than a monohull. Also, as designers create more interior volume in the saloon, they lose wing clearance, or bridgedeck freeboard, between the hulls. This can result in a great deal of pounding and slamming underneath, especially when sailing upwind in big seas.
During a Force-9 gale in the Venezia two years ago, the water action between the hulls was at times so violent it created a 10-foot-high geyser through the bridgedeck scuppers. Beating across the Yucatan Straits in the St. Francis was slow going and in the aft cabins you felt like you were inside a kettledrum. Indeed, as cats tend to slap at every passing wave, the noise requires some acclimation.
…. Cruising cats, as well as many of today's performance monohulls, simply cannot be overloaded. This will not only cause them to lose speed but also to become sluggish and difficult to handle. (One distinct advantage of a heavy-displacement cruising boat is that you can pile on gear and provisions without significantly altering performance.)
The earlier mentioned gale developed out of the southeast shortly after we cleared Cape Hatteras. …
Although the hulls rarely pounded in the rising seas, the water action between the hulls was significant. I didn't question the structural integrity of the boat, but I was surprised at the amount of slamming and slapping that the after-hull sections took. We had a scare when the latch supports of the emergency hatches in both heads broke. Suddenly we had open hatches four inches above the water with no way to secure them. We sacrificed handles from a mop and boathook and lashed them across each hatch. The hatches still leaked but at least the sea was kept out….
Ironically, my initial anxiety about being caught out in a cat gave way to frustration. We were unable to make much progress during the blow. I decided to accept Neptune's fate and shortened sail further, reducing our forward speed to around three knots. .
http://www.sailnet.com/collections/articles/index.cfm?articleid=jkrets006
There are no heavy weight cats. And the movement is what should be expected of a light craft that takes with the same wave twice, first one hull, then on the other, jerky motion is what you get. Not a comfortable boat in troubled waters.
Good for calm waters and for enjoying life when moored and a headache at the time of trying to find a place in a marina and when paying the bill…. prices and places:rolleyes:
Most of the cats I have been on stank as ocean crossers as the performance NEVER exceded the expected hull speed of a lead sled. A 65 ft cat cruising at 8k is hardly worth the risk,cost or dock finding hassles and expense.
FAST FRED
There is a good article about cats at sailnet, by John Kretschmer, a deliver skipper, , that has delivered all kinds of boats, including cats. What he says about the subject is interesting:
“this Fountaine-Pajot Venezia 42 maintained poise as she tracked over the Atlantic, easily coping with the six to eight-foot seas rushing between her hulls.
The Venezia's speed was a consistent seven to eight knots with an occasional low, double-digit spurt when surfing down a wave. My 20-year-old, 44-foot steel ketch could keep pace in these conditions, ....
And cats do sail flat. The lack of rolling downwind is refreshing, especially on a long trade-wind passage. Most of today's cruising cats are well-designed, engineered, and constructed.
But I have discovered compromises. It takes awhile to adjust to the lack of heel, a result of high initial stability, and the ensuing fast, jerky motion. These cats in general have a lot more motion than a monohull. Also, as designers create more interior volume in the saloon, they lose wing clearance, or bridgedeck freeboard, between the hulls. This can result in a great deal of pounding and slamming underneath, especially when sailing upwind in big seas.
During a Force-9 gale in the Venezia two years ago, the water action between the hulls was at times so violent it created a 10-foot-high geyser through the bridgedeck scuppers. Beating across the Yucatan Straits in the St. Francis was slow going and in the aft cabins you felt like you were inside a kettledrum. Indeed, as cats tend to slap at every passing wave, the noise requires some acclimation.
…. Cruising cats, as well as many of today's performance monohulls, simply cannot be overloaded. This will not only cause them to lose speed but also to become sluggish and difficult to handle. (One distinct advantage of a heavy-displacement cruising boat is that you can pile on gear and provisions without significantly altering performance.)
The earlier mentioned gale developed out of the southeast shortly after we cleared Cape Hatteras. …
Although the hulls rarely pounded in the rising seas, the water action between the hulls was significant. I didn't question the structural integrity of the boat, but I was surprised at the amount of slamming and slapping that the after-hull sections took. We had a scare when the latch supports of the emergency hatches in both heads broke. Suddenly we had open hatches four inches above the water with no way to secure them. We sacrificed handles from a mop and boathook and lashed them across each hatch. The hatches still leaked but at least the sea was kept out….
Ironically, my initial anxiety about being caught out in a cat gave way to frustration. We were unable to make much progress during the blow. I decided to accept Neptune's fate and shortened sail further, reducing our forward speed to around three knots. .
http://www.sailnet.com/collections/articles/index.cfm?articleid=jkrets006
Raggi_Thor
05-16-2006, 05:35 AM
There are no heavy weight cats. And the movement is what should be expected of a light craft that takes with the same wave twice, first one hull, then on the other, jerky motion is what you get. Not a comfortable boat in troubled waters.
Good for calm waters and for enjoying life when moored and a headache at the time of trying to find a place in a marina and when paying the bill….
Thats what I thought :-)I don't understand why people want to cross oceans on a jerky platform...
Good for calm waters and for enjoying life when moored and a headache at the time of trying to find a place in a marina and when paying the bill….
Thats what I thought :-)I don't understand why people want to cross oceans on a jerky platform...
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