Motor Sailers?

I agree about Autoprop being probably the wiser choosing for a motorsailer. About sane or insane, well..., I wouldn't be so....direct? (My own good old Marie doesn't mount one! )

Thanks for the link to the book. I'l post it at the Motorsailers & Motorsailings web pages.

 

I love to have one but my side of the data's is not enough..I just want to know an estimation how much will it cost me..

 

"I think anyone with an appropriate sized motorsailor would be absolutely insane not to get an AutoProp. What other propeller continually optimizes itself when using engine and sails simultaneously? "

The question is what is optimum?

With an owner adjustable controllable pitch prop (Hunstad or equal) the vessel can be fine tuned to the current conditions .
A simple prop with just swiveling blades may do fine on an aux sail boat , but motorboats have different requirements.

EG at times motoring or motorsailing the load will be both propulsion and power generation.
With an EGT gage and CP prop the power used can be optomized for the changes in hotel load .

FAST FRED

 

I don’t know the Hunstad propeller that you are talking about, but all the other controllable pitch prop that I know (for yachts) can only be tuned at the propeller and they don’t adapt automatically to any given circumstance as the Autoprop does.

Stephen, that is a relatively expensive propeller and to me it is as useful to a sailboat as to a motorsailor, providing you cruise a lot. Of course if you have a sailboat or a motorsailor and just do some hundred miles a year, it is not going to justify the price.

Fred, I have had one in my sailboat for three years now and I think that you would love it.

When motorsailing, instead of running the engine at 2000rpm or more, you only need 1000rpm, sometimes less. The only problem is that when the wind picks up and you don’t need that extra push to sail at more than 6K, sometimes you forget to turn the engine of, because you can not hear it.

To give you an idea of its efficiency when adapting to different conditions, let me tell you that the speed of my boat with the engine at the idle (ralenti) rpm is around 4k (in flat water and with a clean hull).

 

Because you are talking about designing a "New" boat I didnt respond, but your requirements seem to fit very closely to the boat I just bought and sailed from Tampa FL to Corpus Christi TX (35 days in the GIWW). You may want to consider remaking an older boat to your needs or at least looking at the design of an older boat to adapt what you could use. I will be 70 in September and my wife is 68. We are average in health...in fact I had just had a radical prostatectomy on Feb 13th and we started the trip on May 2nd of this year. The doctor would have been upset if he had known I was doing it. The trip was abouit 400 miles of open water and 1000 miles in protected waters. We wanted a boat suited to our ages but capable.

My wife wanted comfort and I wanted sail. But as you say most sailboats are like living in a cave. The big requirement for us was shallow draft as our slip is only 4 feet at low tide. We had been looking for a power boat without a sail because of the draft requirements.

BUT this boat was offered and it fit our needs. The boat originaly was a 1972 Gulfstar 36 with a center cockpit. The previopus owner took it down to the bare hull and started over. You wanted a pilothouse and ours does not have that, but with enclosing canvas and plastic windows we will have protection from the weather as long as it is not too severe. Since the Gulfstar 36 Trawler used the same hull, you could enclose the center cockpit. The interior has been fully replaced and redesigned from the hull up with a large V Berth forward Gally and large dining area in ONE room, not divided. The aft cabin is a lounge with built in TV entertainment center (my wifes requirement) and full head shower etc.. It too is open and airy. The interior is painted white and gold with very little teak. This contributes to the openness of the cabins. I would have liked more teak, but I must admit to the more roomy feeling of white and gold. We subscribe to the 6-4-2 rule, "6 for cocktails, 4 for dinner, and 2 for overnight." This boat would allow for a second couple in the aft cabin on the setees if need be, but I doubt the "need will be". The dining table will easily seat 4 with lots of room and the center cockpit will handle up to 8.

The hull of the GS 36 is not the pretiest lines you will ever see, but it is wide and roomy which at our age is what we wanted.....after all, I am inside the boat looking out, I dont have to look at its rather plain lines.

The sails are both roller furling as I was getting too old to handle the multiple sails of the Bruce Roberts 44 ketch that we sold when we moved to this boat and my wife DOES NOT DO DECKS, so it had to be a boat I could singlehand. The engine is a Perkins 4-108 4 cyl diesel that uses .671 GPH at cruise and runs the boat at 5.6 Knots at a reasonable RPM.

We just got home on the 6th of June after 35days aboard her and I can honestly say, I have never had a boat more suited to my needs than this boat and my wife agrees...AND we had NO dissagreements or even heated discussions during the entire 35 days. We were both happy and both enjoyed the trip.

 

Nope. Not always

In my boat design class final project, my design had a similer one called a 'Max Prop'. The idea for my proposed motorsailer was to despense with light air sails. They take up more room than several dozen gallons of diesel. When there was sufficient wind, the boat was to go to straight sailboat and the huge prop was supposed to feather to almost no drag.

The diesel was to be very small and expected to drive the 27ft waterline boat at a mere 4kts during a dead calm. I had hoped to trade motoring speed for greater motoring range.

The boat was designed to be inexpensive as possible. The engine didn't even have a transmission. It had a direct belt drive instead. The expensive feathering prop was the only thing I was willing tp splurge on. And that was because it was supposed to pay for itself in saved fuel in a very short time.

Earlier in my studies, I came up with a different concept. This one was supposed to be able to reach hull speed under power but only have a range of a hundred miles or so under power. It was also designed to be simple, sea worthy, and relatively cheap. It had a much bigger engine and a much smaller prop. Efficiency was not to be her strong point. Getting from point A to B in a given time under all but the very worst conditions was.

There are all kinds of ways you can spend money on a boat. Unless you are super wealthy, you had better spend it on what best helps it do its intended purpose the most.

Bob

 

Displacement Glider, PowerKeel, etc

A very interesting new subject thread has recently been posted having to do with a monohull approach to long-range ocean cruising:

Displacement Glider, PowerKeel, etc

One aspect of it I find intriging is the idea of a marriage between the PowerKeel hull concept and Paine's Steadysailer design.

Some of you that have participated in the discussions on this thread might find it rather interesting

 

Now that I see myself quoted I agree with Guillermo that my wording may have been too strong. But I don't agree with Sharpii2 that the MaxProp and the AutoProp are equivalent. When under power and sail simultaneously, the AutoProp will re-pitch itself each time a change in wind speed, or anything else, effects the speed of the vessel. What it's designed to hold constant is the angle of incidence of each blade, at whatever speed the vessel is running, at whatever speed the prop is turning. While the MaxProp may have some nice features, I don't think its self-adjusting in a similar manner.

I think the Hundestat that Fast Fred refers to can be adjusted from inside the vessel. It may be available in larger sizes than the AutoProp... so for larger vessels it may be a good option. Too complex for a smaller yacht, though, it seems to me.

 

That's the way I remember it as well.

I've had two occassions for owners of vessels that tried out the AutoProps to tell me they were not happy with them. Both were on new constructed multihulls. Sorry I do not know the details of either case.

 

The Autoprop only adjusts between certain limits. They have different propellers for different boats, different engines, transmissions, etc (even if they all look the same). If the propeller is badly chosen, it will not work well. They have a lot of experience with the more common models, but adapting one to an unknown model may prove tricky....just guessing

 

Hundestat is the proper spelling.

These controllable pitch props are I believe Danish Mfg.

The units I have sailed with were fully adjustable in pitch from Fwd to Reverse , by cranking a small wheel many turns.

Older boats had reduction gears but no clutches and the prop was merly run to zero pitch to stop.

Fun on starting up the next AM as many diesels will build RPM as they warm , requiring adjustment of either throttle or handwheel to stay in place.

Today most are used with std trannys , to ease docking.

An EGT gage is needed to get the best efficency from these rigs .

These props and their shafting get mounted to a thrust bearing on the hull. This makes vibration isolation and soundproofing of the engine much easier.

FAST FRED

 

Out There Doing It

I just wanted to say "Thank You" for your input. It's great to hear from those people 'out there doing it', particularly at your age, and when they haven't converted over to singularly powerboating.

 

More than that. It makes us (me) dreaming.
I hope I can also do it at that age...and really, guys like you make my hopes and dreams bigger ...and that is great, because living is also dreaming.

Thank you, and best wishes for you and your wife

Sincerely,

Paulo

 

Inspiration to all of us, congratulations Jimisbell!

Mike Richey is another inspirational sailor, sailed solo across Atlantic at the age of 80.
http://www.jesterinfo.org/MikeRichey.html

Milan

 

Hundested used to build engines as well, now days, controllable pitch propeller systems are their core business, but, they are oriented to the bigger boats, their smallest propellers are for the engines of 150 HP.
http://www.hundestedpropeller.dk/?id=4183
Sabb builds CPP systems for smaller engines as well. Their beautiful old fashion 10 HP engine, (unfortunately not longer in production), was sold with a CPP as an standard option!
http://www.sabb.no/eng/homepg.aspx
http://home.no.net/sabb1/

Milan