I'd like to move a Catalina 30 through the water faster, under power....prop change ? Can i get the boat to go 8knots without installing a corvette engine ??
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We were serious.
In still water, unless you can somehow get your displacement hull up on a plane (you'll be the first), 8 knots is not theoretically possible. Assuming you have power in reserve to go beyond hull speed, at some point the prop simply cavitates.
In still water, unless you can somehow get your displacement hull up on a plane (you'll be the first), 8 knots is not theoretically possible. Assuming you have power in reserve to go beyond hull speed, at some point the prop simply cavitates.
Well, our buddy 71175 didn't stick around too long did he?:Liar:
If it is any consolation, I saw the old analog knotmeter get pinned to 10 knots when I was a kid...we surfed down a big wave though...:dance:
How does one actually delete an account if they actually wanted to anyway?
If it is any consolation, I saw the old analog knotmeter get pinned to 10 knots when I was a kid...we surfed down a big wave though...:dance:
How does one actually delete an account if they actually wanted to anyway?
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once you achieve hull speed, not matter how much power is added all you will do is push the bow wave further ahead.
There is a good article in the last issue of Good Old Boat on hull speed. Tells you all you need to know in easy to understand terms.
Dale
Dale
Why do people buy sailboats who want to go really fast? It's about the journey,
and I appreciate going at a rate slow enough to take things in, via the wind. Sounds like he needs to get a Grady White with a big, stinky 250 hp Mercury on the transom, gun it with a Bud in his hand, & then smack into the center channel marker at midnight goin' about 40mph. Unfortunately guys like that really do this, and a firefighter killed a schoolteacher passenger & had a dozen kids in his boat when he did it, with a blood acohol level of over .20. on the Rappohannok River. Never heard of a sailor killing his passengers like that. I hate the stab it-n-steer mentality.
and I appreciate going at a rate slow enough to take things in, via the wind. Sounds like he needs to get a Grady White with a big, stinky 250 hp Mercury on the transom, gun it with a Bud in his hand, & then smack into the center channel marker at midnight goin' about 40mph. Unfortunately guys like that really do this, and a firefighter killed a schoolteacher passenger & had a dozen kids in his boat when he did it, with a blood acohol level of over .20. on the Rappohannok River. Never heard of a sailor killing his passengers like that. I hate the stab it-n-steer mentality.
So what spped do most of you all get? I'm hoping to get an average crusing speed and a fastest speed reached on both sail and motor. I am hoping to buy the catalina 30 next summer to replace my chrysler c-22 and would like to habe an idea of what to expect?
I've got the model 18, which is a 2, the model 25 is a 3. The C27 gross weight is around 7500lbs, ideally suited for the model 18. the C30 is around 10,500-12000lbs depending on how much add ons you have. You start adding AC, fridge, the extra water tank (loaded) etc. and there can be a lot of ballast on a C30 real fast, especially with a full crew. You need the extra hp, and you will never pull a skiier unless you find those cool waves under Golden Gate to ride on. But for comfort and stability it is an awesome boat. Ease of access to engine is another big plus, getting to mine stuffed back under the companionway is an exercise in spelunking.
Glad to know its possible to go faster, and I know it is if you're coasting down a wave, or with a strong current pushing the hull from astern, etc. I used to have a 28 ft S 2 racer /cruiser, and she had a waterline length of only 22.5 ft. & weighed 7,500 lbs. I routinely got her to sail 7.5 knots and as high as 8.3 once. But it takes a lot of wind, good trim & some stout nerves as the rails will be deep in the water! Best I've gotten my new C 30 to is 6.2 knots, with a clean bottom, & 15 - 20 knots of wind, close hauled sailing. Cheers.
The hull speed theory is correct, but this is thru the water speed. under sail, you could reach theses speeeds across the ground by GPS data.
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Let's see......Motor sailing going with the current and surfing a 5 foot wave may let you hit that speed.
sufing down a wave does not change your velocity through the water, it just moves the water - like a current.
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