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  #1  
Old 03-11-2009, 07:02 PM
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gonzo gonzo is offline
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Defining a motorsailor

This is the old debate: what constitutes a motorsailor. Most so called sailboats nowadays are motorsailors. Sailboats fitted with power were originally called auxiliaries. With the availbility of lightweight powerplants the power ratio has increased considerably. Most boats will reach the same speeds under power or sail. That would fulfill the classic definition of a motorsailor.
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Old 03-11-2009, 09:03 PM
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I agree largely.

Personally i define a motorsailor as any boat which has equal or better speed under power than under sail, considering this across all likely conditions.

A sailboat with an auxilliary will have better performance overall under sail than under motor.

Thus most modern production sailboats are in fact, according to my definition, motorsailors.
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Old 03-11-2009, 10:01 PM
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If you consider that the maximum speed is the same under sail or power, but under power you can go upwind, then under power it performs better.
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Old 03-11-2009, 10:15 PM
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I am

Before guillermo has a chance to give us a proper reply, let me give you mine please.

I am a motorsailor! Since 1973 I use motorboats if I´m going to sail........

Regards
Richard
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Old 03-11-2009, 10:48 PM
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to me, it is a vessel that NEEDS her engine turning, to make reasonable progress to weather, no matter what the weather, and needs her engine turning to move her at other sailing angles in light airs
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  #6  
Old 03-13-2009, 05:39 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
I think the modern MS is a 90/90.NOT the old 50/50 of yare.

The loss of 10% of the vessels sailing ability is caused by lugging an engine and all the weight of fuel , spare parts shaft and controls, and perhaps a more burdensome hull..

It can push the vessel to 100% of hull speed , although most will cruise at SL of 1.2 or less to save fuel. The engine allows a good life style as it also serves as power source for electric , refrigeration , hydraulic and sometimes donky or windlass power mechanically.

AS a power vessel the loss is also about 10% from dragging a heavier sailing keel, and dragging all that above deck windage .
A second downside is the height which can create delays for bridges or obstructions if the mast and rig does not lower easily Tabernakle or Lutchet required for coastal work.

Every boat is thousands of compromises the 90/90 would probably be the best compromise for a "world cruiser".

FF
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Old 03-13-2009, 07:03 AM
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all that and the extra speed if you like
i think the concept is even good for cruising cats
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  #8  
Old 03-13-2009, 07:39 AM
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Guillermo Guillermo is offline
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Hi!
You may find a lot of info on motorsailers at my web pages in:
http://www.xente.mundo-r.com/motorsailers/index.htm

From there:

General definition:
"Motorsailers should be, in my opinion, hybrids among sailing boats and motor boats, having amplier volumes than those of a pure sailing boat, as well as a nice pilothouse conceived to steer and navigate (so not being being only a deck or raised saloon) to make them more livable in all kind of weathers; able to carry a generous cargo; have manegeable sails with a short crew (without the needing of very expensive hardware), but able to easily pull the boat as to develope hull speed under sail alone in a moderate breeze (force 4); have a propeller-engine combination allowing for a fuel efficient motoring and having power enough to at least reach hull speed under engine alone, as well as extra muscle to beat dead to winward in a Force 10 storm in protected waters".


We have two main classes, depending on the intended use:


Ocean going (globetrotters) motorsailers:
They use to have an SA/D ratio (loaded) from 13 to 15+ and a HP/(D/1000) ratio around 2 (from now on we'll call this ratio just HP/D). D/Lwl ratio may go from 250 for lighter ones as in designs bred in sailing boats, up to 400+ for old-style heavy-weigths, bred in fishing boats. Fuel tankage should be enough, at least, for around 900-1000 miles under engine alone at 1.1 Speed/Length ratio (Imperial units). Low pilothouse profile, as to allow for structure and windows being capable of resist capsizing and green sea slamming. Relatively high wetted surface for better seamanship. CE Design Category: A


Coastal motorsailers:
These tend to be lighter nowadays and with more powerful engines, although traditional heavy-weights are also here in their own. Fuel tankage is shorter, tipically allowing for 300-400 miles passages. CE Design Category: B or A
Two definite trends:


Northern: Boats designed to usually sail in colder climates and stronger weather. D/Lwl ratio going from 250 to 350 (oldies use to be in the 400+ region), SA/D from 13 to 16 and,and HP/D ratio from 2 to 3 (I consider these boats as being all around short-seas motorsailers, if design category is A).


Southern: Boats rather designed with good-weather islands hopping in mind. D/Lwl in the 200-250 range, very variable SA/D ratio, going from 12-13 up to the 17-18 range, and having an HP/D ratio definitively much higher than 3, some of them going as high as 7 (!) with totally flat sections at the sterns. Fuel hungry boats. Raised deck-saloons rather than pilothouses, in some cases integrated with the cockpit (Be careful: Extreme designs may not even comply with CE design category B!)

Cheers.
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Old 05-11-2009, 05:02 AM
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harlemriverman harlemriverman is offline
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a motor sailer is a vessel that both steams and sails equally poorly.
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Old 05-11-2009, 01:45 PM
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Guillermo Guillermo is offline
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Quote:
Originally Posted by harlemriverman View Post
a motor sailer is a vessel that both steams and sails equally poorly.
You tell that to Brian Eiland (if you dare to.....)
http://www.runningtideyachts.com/home/
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Old 05-11-2009, 08:41 PM
ancient kayaker ancient kayaker is offline
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Quote:
Originally Posted by harlemriverman View Post
a motor sailer is a vessel that both steams and sails equally poorly.
My wife has one of those in the kitchen.
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Old 05-11-2009, 10:06 PM
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Originally Posted by ancient kayaker View Post
My wife has one of those in the kitchen.
a lot of motorsailors motor well, inchcape, silvers, bain, spey class, jones of buckie, watsons, but their not deep hulls for sailing well, plus a lot of top hamper windage, but it really doesnt matter cos there so much fun
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Old 05-12-2009, 02:26 AM
john.G john.G is offline
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I personally like the older classifications of SA (sail auxillary) and AMV (auxillary motor vessel), both of which are motorsailers but it gives a weighting to intended usage.
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  #14  
Old 05-12-2009, 07:13 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
"Personally i define a motorsailor as any boat which has equal or better speed under power than under sail, considering this across all likely conditions."

There must be really few MS for you as most boats , even "good" motor sailors have limited sized engines to avoid the hassles and short service life from under loading a big engine.

Since wind power is almost unlimited , most MS will go faster , can climb really high up the HP required curve with FREE power.

Even a small chute in F 5 or 6 will get most MS sailing far faster than even an outsized engine will .

With dual luffs sewn to a single roller jib , its quire controllable AND produces lift , decreasing the wave making and propelling the boat even faster.

FF
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  #15  
Old 05-14-2009, 07:43 PM
mattotoole mattotoole is offline
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Quote:
Originally Posted by FAST FRED View Post
I think the modern MS is a 90/90.NOT the old 50/50 of yare.

The loss of 10% of the vessels sailing ability is caused by lugging an engine and all the weight of fuel , spare parts shaft and controls, and perhaps a more burdensome hull..

It can push the vessel to 100% of hull speed , although most will cruise at SL of 1.2 or less to save fuel. The engine allows a good life style as it also serves as power source for electric , refrigeration , hydraulic and sometimes donky or windlass power mechanically.

AS a power vessel the loss is also about 10% from dragging a heavier sailing keel, and dragging all that above deck windage .
A second downside is the height which can create delays for bridges or obstructions if the mast and rig does not lower easily Tabernakle or Lutchet required for coastal work.

Every boat is thousands of compromises the 90/90 would probably be the best compromise for a "world cruiser".

FF
I'm with Fast Fred on this.

I spent the last 9 summers on a Maple Leaf 50, a better sailboat than most, and a better powerboat too. Hull speed ~9kt but we cruise at 8-8.5 with our 4 cyl. Lehman. 400gal fuel gives us better range than most trawlers. Some Maple Leafs have more powerful engines installed. If you need more power there's probably wind blowing, so use that!

10kt is easy on a reach in 15kt wind, and we've seen up to 16kt. Averaged 11kt from the Queen Charlotte Islands to Prince Rupert. Not too many cruising sailboats can do that.

Pilothouse? Can't beat the full canvas cockpit cover, at least until there are waves breaking over the boat. Hurricane force winds have been no problem.

I can't see any downsides to this boat, except the big windows offshore. She did fine in 50kt winds and up to 25' seas though, down the CA coast, and out to the Queen Charlottes. Several Maple Leafs are cruising the world.

Maple Leafs are great boats. Builder Forbes Cooper retired, designer Stan Huntingford is no longer with us, and no one else has picked up where they left off. Lots of great ideas in these boats, worth paying attention to.

90/90 for sure.
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