Foils and lift vs speed

cuisto · Post by **cuisto** » Sat Mar 31, 2007 11:35 am

It seems to me there is a simple answer to this and maybe I already know this but let me run this by all of you.

I should not motor at 6mph (manual instuctions) with foils down
1) because of lift generated by center board
2) because I could damage the steering with the high loads on the rudders

I can sail at 17mph (sales prospectus)

The center board thing I think I understand...the lift generated is being compensated for by the pressure on the sails.

The rudder thing I DONT GET strain is strain right??

Any debate of thoughts on this welcome..

Scott

Sloop John B · Post by **Sloop John B** » Sat Mar 31, 2007 11:55 am

Hey Scott,

You have to try it once.

Drop the centerboard and rudders and open her up. The centerboard is sort of wiggly and acts like an aileron on a wing. Just when you think you'll make it back to the beach, the Mac will roll over on its side and toss you into the foam.

Make sure you clip that lanyard from the cutoff switch to your life vest. This will stop the engine and if you're still conscious you can make it back to the boat. The boat most likely will right itself.

Frankly, if it were me, I'd have the Mate take a go at it first.

Night Sailor · Post by **Night Sailor** » Sat Mar 31, 2007 1:22 pm

Cuisto,
That's a question I've pondered too. I could be way off base, but I came up with this: Stain is strain and they are built to take the strain of maximum sailing speed, but the difference I conjecture is, A. the thrust of the motor is at the stern, whereas the thrust of the sails is approx. amidships and somewhat forgiving in both speed and angle of attack. How is sailing forgiving?
Waves or wind gusts affect the boat much differentlly under sail than under relentless motor power. The reason being, I think, when you have winds to make the boat go super fast, you are heeled over at least 15 to 20 degrees, which creates slippage or leeway as you move forward, relieving strain on foils. B. But one motors with the boat straight up and with maximum foil contact with the water, creating more force on the foils.

eric3a · Post by **eric3a** » Sat Mar 31, 2007 2:11 pm

Highlander · Post by **Highlander** » Sat Mar 31, 2007 6:27 pm

Hi Scott

The

power's with the rudders down but they are short & wide plus she has a semi v hull with hard chines their fore she hole shots pretty good & gets up on a plane fairly fast plus with a 40hp eng. with a boat

that weights half of what the

so it is in my opion a better design . Roger stopped building the

because it was to labour intensive for $600. more he could build an

so was the demise of the

after about 1000 productions . but because of her hull design she does not tend to roll like the

I have powered at about 22mph with my c/b down about 1/4 way with no problems

Yeh Ray I love my Pony M . But I got three head sails that I can fly altogether at one time adding 45lbs to the stern as extra ballast

to compensate

what you got

John

Post by **NiceAft** » Sat Mar 31, 2007 7:45 pm

I got chutzpa my friend

Ray

Highlander · Post by **Highlander** » Sun Apr 01, 2007 9:27 am

Hi Ray

Yeh I had to much of that had to give some of it away

I guess your's came with the boat

You know that little white pony M of mine is a little "mustang"

& will kick the butt of that white "Stallion" M of your's

Anytime

John

Post by **NiceAft** » Sun Apr 01, 2007 11:09 am

John,

It's strictly a show horse.

This week I washed and compounded her to a shine. Next I have to wax her real well. Once that is done, I then attack the cockpit. In two weeks she should be ready to take her slip in the marina where, like a true beauty, she will get her appropriate compliments. I take her out for pure sailing enjoyment. Besides, there isn't anyone to race. Actually, I can't say that anymore. Matt is going to keep his boat in the same marina.

Ray

Highlander · Post by **Highlander** » Sun Apr 01, 2007 6:33 pm

Hi Ray

All kidding aside she shure is a reall beauty "WHITE STALLION" I must say you lucky devil , You gotta be mighty "PROUD" But I'll still try to kick your butt

If I ever I get down that way with my wee

I'm gonna roast ya nuts

Post by **NiceAft** » Sun Apr 01, 2007 7:05 pm

Shiver Me Timbers

Now I'm going to have to always be looking over my shoulders and sniffing for 80 proof Monkey Shoulder.

Ray

Highlander · Post by **Highlander** » Sun Apr 01, 2007 7:32 pm

Oh come on Ray

If you've got no Monkey's Shoulder on board I've no reason to "Pirate You ". That was my insentive " My Pillage" I will share ya know I'm not a totall moran 1 shot for you 3 shots for me that sounds fair "No"

what's your home port again

Ya just gota love this mac site Eh

John

Post by **NiceAft** » Sun Apr 01, 2007 8:33 pm

And just where is Georgian Bay John. When I'm up in the Adirondacks this summer, maybe the taste of Monkey's shoulders could get me to make a detour for a day?

Ray

beene · Post by **beene** » Mon Apr 02, 2007 5:59 am

Hi Ray

CLICK HERE

I will be happy to set the record straight for all

owners this summer when I leave the wee

in my wake.

..... and if anyone asks why my 75 was not tilted up at the time, I will just tell them it wont fit under the seat...

G

Catigale · Post by **Catigale** » Mon Apr 02, 2007 11:12 am

Racing keelboats whilst under power and appearing to be sailing is a mean, mean, trick stooping to a new low - I can personally attest that I have never done it in fresh water

beene · Post by **beene** » Tue Apr 03, 2007 7:20 am

...... i heard that steph.......

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Foils and lift vs speed

Foils and lift vs speed