Re: Fin Keel and detached rudder NOT a Lapworth inovation!!!

I don't know if the attachment will survive, but I have attached a photo of the half model of my great grandfather's "Mira", built at the Wood shipyard in City Island in 1899. It has what appears to my eye as a fin keel and a separate (skeg-mounted) rudder. I don't know that Lapworth ever claimed to be the first to use such a configuration. Incidently, "Mira" was campaigned with great success in New York Yacht Club events. As I understand the history, other club members wanted similar results, and commissioned similar designs. Unfortunately, their keels were plate-shaped, in contrast with the foil shape of "Mira". As a result, conventional wisdom decreed that fin keels were no damn good, and they reverted to full keels for a long time. My great grandfather was Charles Lane Poor, a Columbia professor who also wrote "Men Against the Rule", which was a treatise on how sailboat designs took advantage of handicapping rules over the years. Alfred Poor 1969 Cal 29 #132, "Pentaquod"

--- In Ca… [at] yahoogroups.com, "Alfred Poor" <apoor@...> wrote: > > I don't know if the attachment will survive, but I have attached a photo of > the half model of my great grandfather's "Mira", built at the Wood shipyard > in City Island in 1899. It has what appears to my eye as a fin keel and a > separate (skeg-mounted) rudder. I don't know that Lapworth ever claimed to > be the first to use such a configuration. Again, that half model (and it's beautiful) shows a cut away keel but the rudder is still attached. I think we are starting to split hairs here. My point was that separation of the CE of keel and rudder is what makes a spade rudder work. The end plate effect is also an important part of the effect, as someone else pointed out. I think Gerald made a good point about high aspect ratio keels and strength of materials, as well. There are several maxi-boats floating around upside down in the north Pacific after they dropped their keels. A very long, high aspect ratio wing, like that of the B 24 in WWII, can be effective at low speeds but the strength to keep that bulb attached to the hull is crucial. I don't like swing keels, for that reason. They are fraught with trouble. Race boats are built for one season anymore. I couldn't afford that, even if it appealed to me. Anyway, that's enough angels on the head of a pin for me. Mike Kennedy Conquest Cal 40 # 96

SWEET! Whatever happened to her? Wouldn't she be grand today!? Marsh Alfred Poor wrote: > I don't know if the attachment will survive, but I have attached a > photo of the half model of my great grandfather's "Mira", built at the > Wood shipyard in City Island in 1899. It has what appears to my eye as > a fin keel and a separate (skeg-mounted) rudder. I don't know that > Lapworth ever claimed to be the first to use such a configuration. > > > > Incidently, "Mira" was campaigned with great success in New York Yacht > Club events. As I understand the history, other club members wanted > similar results, and commissioned similar designs. Unfortunately, > their keels were plate-shaped, in contrast with the foil shape of > "Mira". As a result, conventional wisdom decreed that fin keels were > no damn good, and they reverted to full keels for a long time. > > > > My great grandfather was Charles Lane Poor, a Columbia professor who > also wrote "Men Against the Rule", which was a treatise on how > sailboat designs took advantage of handicapping rules over the years. > > > > Alfred Poor > > 1969 Cal 29 #132, "Pentaquod" > > > > __ > > > > ------------------------------------------------------------------------ > -- Marsh Wise Webmaster: -reenactor.Net: http://www.reenactor.net/ -Foresthill.us: http://www.foresthill.us/ -Legio IX Hispana Penna: http://www.reenactor.net/units/legio_ix_penna/ - 17. Luftwaffe Feld-Division <coming soon to a website near YOU!> Assistant Webmaster: -VAQ-33 Squadron site: http://www.reenactor.net/vaq-33/ Proud Member (meaning I can just have fun...) -LEGIO IX HISPANA COH III Penna Chapter: http://www.legio-ix-hispana.org/ Netscape Aim/AOL screen name: Sturmkatze Yahoo Messenger screen name: sturmkatze Alteris renumera duplum de quoquo tibi numeraverunt Suppose you were an idiot. And suppose you were a member of Congress.... But then I repeat myself. ~Mark Twain *Last: Hey Dammit! Have you visited the reenactor.Net FORvMS? If not, WHY NOT? Gett your butt over to: http://www.reenactor.net/forums/index.php right now!

I am told that the B-24 glided like a brick. Thanks Charlie From: Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] On Behalf Of mtkennedy1 Sent: Sunday, July 29, 2007 12:00 PM To: Ca… [at] yahoogroups.com Subject: [Cal_Boats] Re: Fin Keel and detached rudder NOT a Lapworth inovation!!! --- In Ca… [at] yahoogroups.com, "Alfred Poor" <apoor@...> wrote: > > I don't know if the attachment will survive, but I have attached a > photo of the half model of my great grandfather's "Mira", built at the > Wood shipyard in City Island in 1899. It has what appears to my eye as > a fin keel and a separate (skeg-mounted) rudder. I don't know that > Lapworth ever claimed to be the first to use such a configuration. Again, that half model (and it's beautiful) shows a cut away keel but the rudder is still attached. I think we are starting to split hairs here. My point was that separation of the CE of keel and rudder is what makes a spade rudder work. The end plate effect is also an important part of the effect, as someone else pointed out. I think Gerald made a good point about high aspect ratio keels and strength of materials, as well. There are several maxi-boats floating around upside down in the north Pacific after they dropped their keels. A very long, high aspect ratio wing, like that of the B 24 in WWII, can be effective at low speeds but the strength to keep that bulb attached to the hull is crucial. I don't like swing keels, for that reason. They are fraught with trouble. Race boats are built for one season anymore. I couldn't afford that, even if it appealed to me. Anyway, that's enough angels on the head of a pin for me. Mike Kennedy Conquest Cal 40 # 96 Yahoo! Groups Links

Speaking of B-24s, if you've flown in the newer 737-800 series with the big Buck Rogers wing tips you've noticed that they just don't want to come down and land. The need to use lots of spoiler action, sticking them big barn doors up out of the wings like a sail plane to get them to come down. The planes just love to keep on flying! Today I ditched a cruiser race to do the demo-daze in a brand new Martin 242, it is the popular 24' one design class here in Marina del Rey, actually and old Canadian design.... and..this is a 1980's technology boat. High aspect ratio fin keel and big main, small jib. She tacked thru.....not my boats 100 degrees, but...70 degrees! The tic tac on the mast showed us going up wind at over 6 knots in squirreling winds behind the apartments and condos, weaving thru the most boat traffic I've seen in years. Talk about responsive steering! And with that glossy gel coat bottom (I'm used to something akin to a bottom that looks like mostly worn away truck tire tread) she hardly slowed down at all through the tacks. I sailed her into the dock, did a 270 just before we entered the slip basin to slow down get around some traffic. She spun so fast that everything was a blur and I nearly launched me first matie Eric off the deck of the boat. Gee Whiz, with the sails, and spartan interior the boat goes for only...$35,000. I think I'll stay with me stately and Cadillac Sedan like Cal 24 a mite longer. Jerry "Husar, Charlie" <hu… [at] bah.com> wrote: I am told that the B-24 glided like a brick. Thanks Charlie -----Original Message----- From: Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] On Behalf Of mtkennedy1 Sent: Sunday, July 29, 2007 12:00 PM To: Ca… [at] yahoogroups.com Subject: [Cal_Boats] Re: Fin Keel and detached rudder NOT a Lapworth inovation!!! --- In Ca… [at] yahoogroups.com, "Alfred Poor" <apoor@...> wrote: > > I don't know if the attachment will survive, but I have attached a > photo of the half model of my great grandfather's "Mira", built at the > Wood shipyard in City Island in 1899. It has what appears to my eye as > a fin keel and a separate (skeg-mounted) rudder. I don't know that > Lapworth ever claimed to be the first to use such a configuration. Again, that half model (and it's beautiful) shows a cut away keel but the rudder is still attached. I think we are starting to split hairs here. My point was that separation of the CE of keel and rudder is what makes a spade rudder work. The end plate effect is also an important part of the effect, as someone else pointed out. I think Gerald made a good point about high aspect ratio keels and strength of materials, as well. There are several maxi-boats floating around upside down in the north Pacific after they dropped their keels. A very long, high aspect ratio wing, like that of the B 24 in WWII, can be effective at low speeds but the strength to keep that bulb attached to the hull is crucial. I don't like swing keels, for that reason. They are fraught with trouble. Race boats are built for one season anymore. I couldn't afford that, even if it appealed to me. Anyway, that's enough angels on the head of a pin for me. Mike Kennedy Conquest Cal 40 # 96 Yahoo! Groups Links