[Rhodes22-list] How fast does your R22 go?

[Blue Heron]

Is there an R22 in this?

http://www.youtube.com/watch?v=nDToL593cmU

Rick

On Sun, Jan 25, 2009 at 4:21 PM, Ronald Lipton <ronald.lipton at gmail.com>wrote:

> Some gratuitous physics (mostly from the "Symmetry of Sail").
>
> Hull speed occurs when the speed of the wave front generated by the
> bow wave has the same wavelength as the boat.  At that point the
> boat has to "climb it's own wave".  Wavelength and velocity for a
> a water wave are related by V = sqrt(gL/2pi).
> Most of you know that, but there is an exception:
>
>  In water which is shallow compared to the
> wavelengh wave propagation is dominated by the depth - and for the
> longer wavelengths  V = sqrt(gD) (D is the Depth) or
> V(knots) = 6.2*sqrt(D(meters).  This means that the effective "depth
> speed" in shallow water is much larger than that at larger depth for a
> small boat.
> This also means that all waves, of whatever wavelength,  generated below
> "depth speed" move ahead of the boat, decreasing wave friction.  However
> the bow wave at "depth speed" would be enormous.
>
> Wave drag is one component of the drag forces on a boat. The other
> major forces are skin frictional resistance and vortex drag.  Skin
> friction appears
> to dominate until about 2/3 of hull speed.  Wave drag goes "through the
> roof" with
> respect to the other drag forces as the nominal hull speed is exceeded.
>
> Ron
>
>
> Eric Nelson wrote:
> > Imagine my suprise to see this. GPS was reading between 8.5 and 9 MPH.
> Was
> > lots of fun since the slightest tug on the Main Sheet would send the boat
> > heeling, and my wife and daughter screaming. Only lasted about 5 minutes,
> > but long enough to snap this photo.
> > ----- Original Message -----
> > From: "TN Rhodey" <tnrhodey at gmail.com>
> > To: "The Rhodes 22 Email List" <rhodes22-list at rhodes22.org>
> > Sent: Sunday, January 25, 2009 5:20 AM
> > Subject: Re: [Rhodes22-list] How fast does your R22 go?
> >
> >
> >
> >> Sailing on lake/river I can motor 6 knots with my 6 hp motor wide open.
> >> This
> >> may seem hard to believe but I have toppped 7 knots a couple of times
> >> under
> >> sail. This speed was sustained for periods of around 5 minutes or so and
> >> was
> >> on a run that turned into a reach that turned into a broach.
> >>
> >> The first time happened in a race under very windy conditions (20+). I
> >> posted this story 6 or so years ago. It was in January with temps in the
> >> 30s
> >> and snow on the ground/. The conditions were such that we only had 7
> boats
> >> in the race. Two pulled out right after the start. A Catalina 30
> shredded
> >> their main. A husband/wife crew didn'tt think their marriage would
> survive
> >> the race. We were now down to 5 boats.
> >>
> >> I was sailing my R22 single handed with with 60% furled main and a 125
> >> jib.
> >> The RC didn't want to mess with buoys because it was so cold. The race
> >> course was around Half Moon Island and back through the starting gate.
> It
> >> was upwind towards the island. The wind was really blowing, the sky was
> >> gray, and then it started snowing. I was over powered several times and
> >> had
> >> a hard time keeping flat. By staying in the shallow side in the lee of
> the
> >> island I was able to shorten the course and find some calmer weather. I
> >> decided to unfurl the main to take advantage of the lull.
> >>
> >> Once crossing the island I jibed to turn back towards the finish line. I
> >> was
> >> no longer in the lee and the boat took off like a rocket. My GPS was
> >> showing
> >> a steady 7 plus knots for minutes at a time with occasional bursts going
> >> over 9. It was not a smooth ride as the boat kept wanting to head up.
> >> Finally the boat was over powered and broached. Rudder control was
> useless
> >> at this point and I rounded up heeling hard.. I furled the main back in
> >> and
> >> ran the rest of the way to the line chugging along at 6 - 7 knots
> steady.
> >> Note this is measured speed over ground. I do not have knot meter. I
> can't
> >> remember the results but i remember I finished 4 out of 5. I beat a
> >> Newport
> >> 28 before they corrected the time! I think I corrected to 2 or 3.
> >>
> >> Remember hull speed is only theoretical. The RC measured wind speed that
> >> day
> >> at 18-23 with gusts measured over 30.
> >>
> >> Fair Winds,
> >>
> >> Wally
> >>
> >> On Sun, Jan 25, 2009 at 7:36 AM, Metaphor <mwager at bluecrab.org> wrote:
> >>
> >>
> >>> I had it up to about 70 on the way to the put-in ramp, but I got kind
> of
> >>> scared when it started heeling too much around the turns, so I backed
> it
> >>> down to the 50 mph speed limit...
> >>>
> >>> --
> >>> View this message in context:
> >>>
> http://www.nabble.com/How-fast-does-your-R22-go--tp21641761p21651283.html
> >>>  Sent from the Rhodes 22 mailing list archive at Nabble.com.
> >>>
> >>> __________________________________________________
> >>> To subscribe/unsubscribe or for help with using the mailing list go to
> >>> http://www.rhodes22.org/list
> >>> __________________________________________________
> >>>
> >>>
> >> __________________________________________________
> >> To subscribe/unsubscribe or for help with using the mailing list go to
> >> http://www.rhodes22.org/list
> >> __________________________________________________
> >>
> >>
> > -------------- next part --------------
> > A non-text attachment was scrubbed...
> > Name: DSC00219.JPG
> > Type: image/jpeg
> > Size: 37645 bytes
> > Desc: not available
> > Url :
> http://www.rhodes22.org/pipermail/rhodes22-list/attachments/20090125/261e560b/attachment.JPG
> > __________________________________________________
> > To subscribe/unsubscribe or for help with using the mailing list go to
> http://www.rhodes22.org/list
> > __________________________________________________
> >
>
> __________________________________________________
> To subscribe/unsubscribe or for help with using the mailing list go to
> http://www.rhodes22.org/list
> __________________________________________________
>