Home |
Search |
Today's Posts |
|
#1
![]() |
|||
|
|||
![]()
If you ever get up the nerve again to motor down the Ditch to
Key West give me a shout when you get near Key Largo. I'll race you to Marathon and no motors allowed. You will be sooooo far behind. "Jeff Morris" jeffmo@NoSpam-sv-lokiDOTcom wrote in message ... Neal is thinking of his boat - for him a 25 mile trip is an all-day passage. In the light LIS wind, it could be an overnight. wrote in message ... On Wed, 23 Jul 2003 17:08:17 -0400, "Simple Simon" wrote: What a pathetic sailing trip. It's all schedule and land-based. Why not just drive an automobile? You aren't sailing anyway; your are going to end up motoring just to keep on schedule. Why would we need to motor at all? No leg is more than about 25 nm. Most sailing does start and end on land. I guess you were unaware of that, being a non-sailor, and all... BB |
#2
![]() |
|||
|
|||
![]()
"Simple Simon" wrote in message
... If you ever get up the nerve again to motor down the Ditch to Key West give me a shout when you get near Key Largo. I'll race you to Marathon and no motors allowed. You will be sooooo far behind. That is such a pathetic challenge - its hard to see how you could keep up with me for 5 minutes. For starters, my SA/disp is over 20, while yours is about 14.25. This predicts the speed, as a percentage of hullspeed, for a given wind. Meanwhile, my hull speed (not that I'm constrained by it, as you are) is about 8 knots. Your hull speed is about 6.3 knots. I don't have the Polar diagram for either boat, but lets try to do a VPP-like prediction, based on published data and tables. In a 14 knot breeze, a sail generates 0.02 HP per square foot. For you, that's 6 HP, or 1040 pounds/hp; for me that 10.8, which is 815 pounds/hp. This means (using a table) that you'll move at about 1.05 times the sqrt of your waterline, or 1.05x4.7 or 4.9 knots. My boat, on the other hand, will be at 1.14 x sqrt(WL), or 6.7 knots, or 36 percent faster. I'm not even considering that my boat goes faster than the table predicts, because of the very narrow effective beam of the individual hulls. Your boat will get to its 6.3 knot hull speed at some point around 20 knots breeze - at which time I'll be flying away at 10+ knots. At low speed, in a 10 knot wind you'll be at 4.5 knots; I'll be at 6.2 knots. BTW, these number are fairly good predictors - I'm a tad slower than the 10 knot wind prediction, a tad faster than the 14 knot. This makes sense, since at low speed the wetted surface affects me more than a normal boat; at higher speed I have less wave making resistance. You can talk about your 130 jib, but I have one too. Or your chute, but I have a new asymm. How about your main, is it a 3 year old modern full batten main or a blown out old bag? Do you have any chance? In light air anything can happen. And you certainly have local knowledge. Short tacking up a narrow channel would not be pleasant for me. Upwind, the margin might be a bit closer, though your shoal draft keel doesn't help you much. But on a relatively open course, in any wind over, say 8 knots, I'll be going 35% faster than you, or more. The last time I went by your mooring I was doing 8-9 knots, and averaged that for the entire day. Frankly, unless there's a dramatic change in my life, I don't think I'll get my boat down there again for a few more years (though I may be driving by at Christmas). Why don't you bring your fine bluewater craft up here next Summer? -jeff www.sv-loki.com "The sea was angry that day, my friend. Like an old man trying to send back soup at the deli." |
#3
![]() |
|||
|
|||
![]()
The water is too polluted up there for my liking and the winds
too unreliable. Then, there's the people of whom Bobsprit is a good example. I would have to be crazy to go up there by choice. The reason I would probably beat you in a race from Key Largo to Marathon is local knowledge (shortcuts, etc.) and unless there was enough wind for you to reach hull speed I would beat your boat because mine goes faster in lighter winds. Yours has too much drag from propellers and the extra wetted surface of two hulls. Also, I can hang proportionately more sail area than you can. "Jeff Morris" jeffmo@NoSpam-sv-lokiDOTcom wrote in message ... "Simple Simon" wrote in message ... If you ever get up the nerve again to motor down the Ditch to Key West give me a shout when you get near Key Largo. I'll race you to Marathon and no motors allowed. You will be sooooo far behind. That is such a pathetic challenge - its hard to see how you could keep up with me for 5 minutes. For starters, my SA/disp is over 20, while yours is about 14.25. This predicts the speed, as a percentage of hullspeed, for a given wind. Meanwhile, my hull speed (not that I'm constrained by it, as you are) is about 8 knots. Your hull speed is about 6.3 knots. I don't have the Polar diagram for either boat, but lets try to do a VPP-like prediction, based on published data and tables. In a 14 knot breeze, a sail generates 0.02 HP per square foot. For you, that's 6 HP, or 1040 pounds/hp; for me that 10.8, which is 815 pounds/hp. This means (using a table) that you'll move at about 1.05 times the sqrt of your waterline, or 1.05x4.7 or 4.9 knots. My boat, on the other hand, will be at 1.14 x sqrt(WL), or 6.7 knots, or 36 percent faster. I'm not even considering that my boat goes faster than the table predicts, because of the very narrow effective beam of the individual hulls. Your boat will get to its 6.3 knot hull speed at some point around 20 knots breeze - at which time I'll be flying away at 10+ knots. At low speed, in a 10 knot wind you'll be at 4.5 knots; I'll be at 6.2 knots. BTW, these number are fairly good predictors - I'm a tad slower than the 10 knot wind prediction, a tad faster than the 14 knot. This makes sense, since at low speed the wetted surface affects me more than a normal boat; at higher speed I have less wave making resistance. You can talk about your 130 jib, but I have one too. Or your chute, but I have a new asymm. How about your main, is it a 3 year old modern full batten main or a blown out old bag? Do you have any chance? In light air anything can happen. And you certainly have local knowledge. Short tacking up a narrow channel would not be pleasant for me. Upwind, the margin might be a bit closer, though your shoal draft keel doesn't help you much. But on a relatively open course, in any wind over, say 8 knots, I'll be going 35% faster than you, or more. The last time I went by your mooring I was doing 8-9 knots, and averaged that for the entire day. Frankly, unless there's a dramatic change in my life, I don't think I'll get my boat down there again for a few more years (though I may be driving by at Christmas). Why don't you bring your fine bluewater craft up here next Summer? -jeff www.sv-loki.com "The sea was angry that day, my friend. Like an old man trying to send back soup at the deli." |
#4
![]() |
|||
|
|||
![]()
Neal wrote...
The reason I would probably beat you in a race from Key Largo to Marathon is my big outboard |
#5
![]() |
|||
|
|||
![]()
Yours has too much drag from propellers and
the extra wetted surface of two hulls. Of course Neal knows that his boat is slow, but this is still entertaining. RB |
#6
![]() |
|||
|
|||
![]()
My boat is faster in light winds than your C&C which stands
for Crud and Crudier. "CANDChelp" wrote in message ... Yours has too much drag from propellers and the extra wetted surface of two hulls. Of course Neal knows that his boat is slow, but this is still entertaining. RB |
#7
![]() |
|||
|
|||
![]()
Alas it is not because he will be motoring
Cheers MC Simple Simon wrote: My boat is faster in light winds than your C&C which stands for Crud and Crudier. "CANDChelp" wrote in message ... Yours has too much drag from propellers and the extra wetted surface of two hulls. Of course Neal knows that his boat is slow, but this is still entertaining. RB |
#8
![]() |
|||
|
|||
![]()
Your local knowledge would certainly help in such confined waters, but remember that I
draw less than you do, even with you shoal draft keel. I don't have to reach my hull speed; I sail above your hull speed in 12 knots. I doubt your boat goes faster than mine in light air - even if you did get way on the first powerboat wake would set you rolling for 15 minutes. My props are folding, though I do have drag from saildrives and a bit of extra surface. I don't think you can add much sail. We both have 130s, and your 150 only adds about 30 square feet. I can carry my asymm a lot closer than you can carry your chute. The simple truth is that although my PDQ is not a speedster by multihull standards, it is substantially fast than most monohulls under 40 feet. "Simple Simon" wrote in message ... The water is too polluted up there for my liking and the winds too unreliable. Then, there's the people of whom Bobsprit is a good example. I would have to be crazy to go up there by choice. The reason I would probably beat you in a race from Key Largo to Marathon is local knowledge (shortcuts, etc.) and unless there was enough wind for you to reach hull speed I would beat your boat because mine goes faster in lighter winds. Yours has too much drag from propellers and the extra wetted surface of two hulls. Also, I can hang proportionately more sail area than you can. "Jeff Morris" jeffmo@NoSpam-sv-lokiDOTcom wrote in message ... "Simple Simon" wrote in message ... If you ever get up the nerve again to motor down the Ditch to Key West give me a shout when you get near Key Largo. I'll race you to Marathon and no motors allowed. You will be sooooo far behind. That is such a pathetic challenge - its hard to see how you could keep up with me for 5 minutes. For starters, my SA/disp is over 20, while yours is about 14.25. This predicts the speed, as a percentage of hullspeed, for a given wind. Meanwhile, my hull speed (not that I'm constrained by it, as you are) is about 8 knots. Your hull speed is about 6.3 knots. I don't have the Polar diagram for either boat, but lets try to do a VPP-like prediction, based on published data and tables. In a 14 knot breeze, a sail generates 0.02 HP per square foot. For you, that's 6 HP, or 1040 pounds/hp; for me that 10.8, which is 815 pounds/hp. This means (using a table) that you'll move at about 1.05 times the sqrt of your waterline, or 1.05x4.7 or 4.9 knots. My boat, on the other hand, will be at 1.14 x sqrt(WL), or 6.7 knots, or 36 percent faster. I'm not even considering that my boat goes faster than the table predicts, because of the very narrow effective beam of the individual hulls. Your boat will get to its 6.3 knot hull speed at some point around 20 knots breeze - at which time I'll be flying away at 10+ knots. At low speed, in a 10 knot wind you'll be at 4.5 knots; I'll be at 6.2 knots. BTW, these number are fairly good predictors - I'm a tad slower than the 10 knot wind prediction, a tad faster than the 14 knot. This makes sense, since at low speed the wetted surface affects me more than a normal boat; at higher speed I have less wave making resistance. You can talk about your 130 jib, but I have one too. Or your chute, but I have a new asymm. How about your main, is it a 3 year old modern full batten main or a blown out old bag? Do you have any chance? In light air anything can happen. And you certainly have local knowledge. Short tacking up a narrow channel would not be pleasant for me. Upwind, the margin might be a bit closer, though your shoal draft keel doesn't help you much. But on a relatively open course, in any wind over, say 8 knots, I'll be going 35% faster than you, or more. The last time I went by your mooring I was doing 8-9 knots, and averaged that for the entire day. Frankly, unless there's a dramatic change in my life, I don't think I'll get my boat down there again for a few more years (though I may be driving by at Christmas). Why don't you bring your fine bluewater craft up here next Summer? -jeff www.sv-loki.com "The sea was angry that day, my friend. Like an old man trying to send back soup at the deli." |