[C320-list] How fast have you sailed

[Jeff Hare]

Right, theoretical hull speed on our boat is somewhere around 7.2kts (~8.3mph).  I'd believe you can go a little bit faster under ideal conditions maybe in the 7.5kt range through very flat water with clean hull and aftermarket sails.  8.5kts?  I highly doubt there is any way to sustain that kind of speed in the C320 under sail.  I'd have to see some proof that the kt meter was calibrated using timed, measured nautical mile runs on a lake where there is no current or tide.  The knot meters can be calibrated with GPS speed over ground using fixed distance (1 kt mile) timed runs both down and back then averaged.  On a calm flat day you can do this with engine power at a fixed speed and get a more accurate calibration.

Some exceptions to this might be if you had high tech racing sails and really know how to tune the heck out of them. I've seen people sail pretty fast in a 320 but not that fast!

We often see mid 7's kts on the GPS (VMG) in ocean in flat conditions with good wind using *tidal* currents to assist, but true through the water speed is rarely over 7.5kts sustained for any length of time. We also surfed down a big wave or two and saw 15kts on the way down, but that doesn't count since it cannot be sustained once the following wave passes and half the crew needed to change their underwear after that.

I will say that we ran home from Nantucket one year with Hurricane Bill blowing 38+kts on the port quarter behind us and of course following seas.  We had the fastest sail home.  Lots of surfing, full sails but speed through the water never really went much over 7.5kts for more than a few seconds at a time, followed by a dip in speed when the wave passed.  You could clearly see the bow wave we were building up in front of us when we reached that speed.  It was a glorious and relaxing sail and the poor dude going the other direction was getting the snot pounded out of him.  Note: We're usually *that* guy...

The Polar charts for the 320 are about relative speeds through the water.  Ie, close reaching is slower than running on a broad reach.   You can pretty much completely disregard the actual speed numbers themselves.  Those actual speeds are unattainable.  If you follow the polars, they show that the fastest point of sail is with wind coming in 120 degrees off the nose (Stern quarter).  Actually wind coming in on the port quarter is better because of the boat's natural port list.

I once sailed along with another boat that I kept catching and passing.  At one point we turned around and went the other direction to kill a bit of time to stay together.  He mentioned that he was surprised how fast our boat was because he was flying along at 9kts much of the time.  Just smile and nod at that point.  LOL!

Fastest my boat's ever been?  ~75mph down the interstate.  :)

My $.02 of course... 
-Jeff Hare
#809



-----Original Message-----
From: C320-list [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Greg Flanagan
Sent: Sunday, September 3, 2017 2:09 PM
To: C320-List at Catalina320.com
Subject: Re: [C320-list] How fast have you sailed

Interesting discussion. Many comments o not indicate if using GPS speed or boat speed. If the latter are they sure their sending unit has been calibrated correctly? I have exceeded 10 knots GPS speed. However, this included an underlying positive current. 

Displacement boats can only go so fast regardless of motive force. 

As a very general rule the maximum speed of any displacement hull--commonly called its hull speed--is governed by a simple formula: hull speed in knots equals 1.34 times the square root of the waterline length in feet (HS = 1.34 x √LWL.

As the 320 has a LWL pf 28.0 ft. The maximum hull speed is ~ 7 knots.  I doubt anyone has exceeded this. 

Cheers,,

Greg
Sidney, BC
Hoop Dancer #1076

> On Sep 1, 2017, at 8:53 PM, Rick Sulewski <rsulewski at bex.net> wrote:
> 
> In my second season with our then new 320 we logged 8.5 knots (9.7 mph top speed) in 25 knots with gusts up to 30 on a close reach going partial off wind. Didn't know what we did not know at that time. We learned that we cannot out sail the boat, but could find ourselves humbled by the sailing conditions. We were getting beat up trying to make headway against 8 footers in Western Lake Erie in 25 ft. depths, that produced very sharp waves as a cold front was passing through. When we finally got tired of experiencing shock loads on the rigging beating toward our Kelleys Island destination under a single reefed main, we fell off for a time to go where the wind wanted to take us on a reach until the gusts subsided to the mid-twenties, after about a half-hour. The problem was controlling the hull as we gained speed heading down into the trough because as we went up and over the hull wanted to roll on the way down resulting in having to  make a correction and place the bow into the next wave with water coming over the closed hatch and into the cockpit. Exciting, but not much more comfortable. Since one knot is equal to 1.15 mph, I surmised we probably exceeded 10 mph. but was too busy sitting on the high side working the wheel to notice the speed instrument.  The older speed instrument often logged (trapped) lower knot speeds than what was monetarily displayed as a higher speed. Lessons learned, we installed exterior grab handles on both sides of the companionway and stopped using the jam cleat to control the main in high winds.  It was impossible to release the line from the jam cleat in 25- 30 knots and had to momentarily head up  directly into the wind to free the jam cleat to transfer the main sheet to the winch before we could fall off while in the wave trough as we approached the next steep ridge. After that experience we decided not to leave the dock in winds higher than 20-22 knots or when waves exceed 6 feet. Also learned to understand and respect the practical application of the Beaufort Scale translated into the relationship between wind force and wind speed!
> Rick Sulewski
> 95' C320 Hull 277 My-Ria
> 
> -----Original Message-----
> From: C320-list [mailto:c320-list-bounces at lists.catalina320.com] On 
> Behalf Of Doug Treff
> Sent: Friday, September 01, 2017 10:10 PM
> To: c320-list at lists.catalina320.com
> Subject: Re: [C320-list] How fast have you sailed
> 
> I once hit 10.1 on a broad reach surfing down a wave with only half my genoa and no main in 25+ knots a while back.
> 
> --
> Doug Treff
> doug at treff.us
> 
>> On Fri, Sep 1, 2017, at 10:07 PM, Dan Kolean wrote:
>> Had my fastest sail to date. 2nd season on the boat.  Beam reach, 
>> steady apparent above 15mph, sometimes 20mph. 1 reef in main, couple 
>> wraps on the 135 original jib.  Topped at 9.8MPH on the GPS.  I had 
>> no idea the boat could sail that fast. We headed up on the puffs, 
>> then fell off to the beam reach and the boat flattened out and that's 
>> when we got the good speed.  Anyone get their 320 over 10mph?
>> 
>> Dan Kolean. #489
>> Mary Kate
>> Holland MI
>> 
>> Sent from my iPad
>