8.0 speed

dorourke · #1 (**permalink**) 07-31-2007

Anyone and everyone who has an 8.0 reading this thread:

I would like to know how fast you've had your sailboat. I recently sailed in twenty knot winds and I think I've had her clocked at 7.2 knots. The knot meter only read at 5.2 knots at most but I have since gone over the course with a chart and calculated the distance and time and have concluded the speed to be an average of 7.2 knots. Can the 8.0 do that speed? I will also re-calibrate my knot meter. Could I be wrong?

I had on the same day been ahead of a Catalina 32 for the length of the trip and he only creeped up on me. I still beat him,

I'm curious, let me know!

SanderO · #2 (**permalink**) 07-31-2007

I have a B&G speed log which there are a number of ways to calibrate. Since there is always some current running the calibration requires a number of runs of a measured distance.

But if the bottom is fouled at all or the tranasducer is... which happens over time because of marine growth, the transducer performance changes. The GPS SOG gives an accurate reading of the speed, but not through the water and of course a computation of a course over time can give you an average speed. I have seen boat speeds of over 8 knots recently on a reach in flat seas and winds of 18 or so true. That is pretty hard to sustain for more than a few minutes, but I can hold the mid 7's in good conditions. With a fair current I have seen SOG as high as 9 and once in the race 11 for a few minutes. On ocean passages we can do 150 and have done 170. MY LWL is 29'. A clean bottom and prop makes a big difference and towing a dink slows you down as well.

jef
sv shiva

timangiel · #3 (**permalink**) 08-02-2007

I have a 8.0 and my knot meter has read 7.2 several times this season and a bit higher on a few occasions. I have no problem believing you when you say you have done it, although the accuracy of the knot meter can be debated forever, I pretty much believe my knot meter.

dorourke · #4 (**permalink**) 08-07-2007

Sorry it took so long to get back to this thread, someone sent over a virus that locked everything up including all my photos.

The PHRF rating on the 8.0 is 222, if you go by the square root formula of the hull you should only be able to do 5.2 knots. The PHRF rating on a Catalina 27 is 204. He owes me 18 seconds a mile. I have sailed with a friend who owns a Catalina and we rarly got to 6 knots. I think my next investment will be a GPS so I can calibrate properly and truelloy know my speed.

Gary M · #5 (**permalink**) 08-07-2007

Where you running or going to windward ? Certainly running in a big wind will cause you to plane/surf and you can average a speed greater than your hull speed. If you are going to windward however the laws of physics step in and you cannot do more than your hull speed. Likely just over 6 knots.

I have an S2 9.1 and would never expeect it to go much more than about 6.5-6.6 knots upwind.

Gary

dorourke · #6 (**permalink**) 08-07-2007

Gary,

We were on a broad reach with following seas, the wind was an almost steady 20 knots, waves were three to six feet and the ride was not smooth. I can understand the surfing but much of the time I had to steer parallel with the waves to hold course. Several times while going close reach my knot meter showed 4.5 knots and the wind was twelve knots or so. If the ratio is correct (7.2 x 4.5 dev. by 5.5) I should have been doing 5.8 knots but that seems too high. I'm just trying to get a feal for the boat and learn it.

rperret · #7 (**permalink**) 08-07-2007

For a basis of comparison - I own an S2 27.

During a race it was probably blowing bet 18-24 knots (one guy on a Beneteau claimed is anemometer hit 28 knots going to windward) with 3 foot seas. I had a reefed main, and about 1/2 of my jib unfurled.

On a broad reach with following seas we hit 7.8 knots per my knotmeter. I know were going fast because the sound the rudder made going thru the water was louder than any time I can recall.

I looked at an 8.0 before buying the 27. Its a nice boat and hope you enjoy it!

Rick
Fairfield, CT

dorourke · #8 (**permalink**) 08-09-2007

Quote:

Originally Posted by rperret

I looked at an 8.0 before buying the 27. Its a nice boat and hope you enjoy it!

Rick
Fairfield, CT

Rick,
I love this boat. It is the best handling sailboat for it's size in my opinion. I had the rudder fluttering several times while going to weather on our way to the island and was reading 5.7 knots on the un-calibrated knot meter. We had the 150 and full main pulling hard while fighting a slight weather helm, OH WHAT FUN!!