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Possibly a major flaw in sailboat design?
In contemplating sailboat design I think I have found a fundamental flaw,
that when corrected should yield a great improvement in sailboat performance. The flaw is that the keel is put before the rudder. I believe this legacy continues in modern designs because of accident. The rudder rightfully belongs in front of the keel, not behind it for reasons that shall become obvious upon further reading. Firstly, think of cars and motorcycles. Are they steered by rear wheels? Mostly not and with good reason, the steering is better done by the front wheels. In making a turn, the front mounted rudder would direct an increased water flow to one side of the keel which would increase the effectiveness (lift) of the keel - keep the boat upright , the sails would have more power, the boat less leeway and the turn executed much more quickly. In heavy seas, the forward mounted rudder would provide greater stability and control because of its beneficial redirection of water to one side of the keel. Docking and tight maneuvers would also be much easier because the bow is steered, rather than the stern. Under power, the propeller would be many times efficient. The rudder would not be blocking the thrust of the propeller nor inefficiently redirecting it. The rudder could be configured to alter the characteristics of the bow wave which would increase the hull speed and overall speed of the boat. Just like railroad tracks are the width of a horse's ass, rear mounted rudders are the result of the legacy of dry helmsman. In these modern times it's very practical to put a rudder under the bow and enjoy the increased performance benefits. |
Possibly a major flaw in sailboat design?
On Thu, 4 Dec 2008 11:24:44 -0700, "Charles Momsen"
wrote: In contemplating sailboat design I think I have found a fundamental flaw, that when corrected should yield a great improvement in sailboat performance. The flaw is that the keel is put before the rudder. I believe this legacy continues in modern designs because of accident. The rudder rightfully belongs in front of the keel, not behind it for reasons that shall become obvious upon further reading. Firstly, think of cars and motorcycles. Are they steered by rear wheels? Mostly not and with good reason, the steering is better done by the front wheels. In making a turn, the front mounted rudder would direct an increased water flow to one side of the keel which would increase the effectiveness (lift) of the keel - keep the boat upright , the sails would have more power, the boat less leeway and the turn executed much more quickly. In heavy seas, the forward mounted rudder would provide greater stability and control because of its beneficial redirection of water to one side of the keel. Docking and tight maneuvers would also be much easier because the bow is steered, rather than the stern. Under power, the propeller would be many times efficient. The rudder would not be blocking the thrust of the propeller nor inefficiently redirecting it. The rudder could be configured to alter the characteristics of the bow wave which would increase the hull speed and overall speed of the boat. Just like railroad tracks are the width of a horse's ass, rear mounted rudders are the result of the legacy of dry helmsman. In these modern times it's very practical to put a rudder under the bow and enjoy the increased performance benefits. Unfortunately the water deflected by the forward rudder is so turbulent that it destroys laminar flow over the keel. OzOne of the three twins I welcome you to Crackerbox Palace. |
Possibly a major flaw in sailboat design?
OzOne wrote in message ... On Thu, 4 Dec 2008 11:24:44 -0700, "Charles Momsen" wrote: In contemplating sailboat design I think I have found a fundamental flaw, that when corrected should yield a great improvement in sailboat performance. The flaw is that the keel is put before the rudder. I believe this legacy continues in modern designs because of accident. The rudder rightfully belongs in front of the keel, not behind it for reasons that shall become obvious upon further reading. Firstly, think of cars and motorcycles. Are they steered by rear wheels? Mostly not and with good reason, the steering is better done by the front wheels. In making a turn, the front mounted rudder would direct an increased water flow to one side of the keel which would increase the effectiveness (lift) of the keel - keep the boat upright , the sails would have more power, the boat less leeway and the turn executed much more quickly. In heavy seas, the forward mounted rudder would provide greater stability and control because of its beneficial redirection of water to one side of the keel. Docking and tight maneuvers would also be much easier because the bow is steered, rather than the stern. Under power, the propeller would be many times efficient. The rudder would not be blocking the thrust of the propeller nor inefficiently redirecting it. The rudder could be configured to alter the characteristics of the bow wave which would increase the hull speed and overall speed of the boat. Just like railroad tracks are the width of a horse's ass, rear mounted rudders are the result of the legacy of dry helmsman. In these modern times it's very practical to put a rudder under the bow and enjoy the increased performance benefits. Unfortunately the water deflected by the forward rudder is so turbulent that it destroys laminar flow over the keel. Likewise for the alternative arrangement, during any type of turning of the boat the keel would generate turbulent flow that would destroy laminar flow about a rudder behind it. Both generalizations may be true in some instances but not in all instances. |
Possibly a major flaw in sailboat design?
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Possibly a major flaw in sailboat design?
On Thu, 4 Dec 2008 16:16:23 -0700, "Charles Momsen"
wrote: OzOne wrote in message ... On Thu, 4 Dec 2008 11:24:44 -0700, "Charles Momsen" wrote: In contemplating sailboat design I think I have found a fundamental flaw, that when corrected should yield a great improvement in sailboat performance. The flaw is that the keel is put before the rudder. I believe this legacy continues in modern designs because of accident. The rudder rightfully belongs in front of the keel, not behind it for reasons that shall become obvious upon further reading. Firstly, think of cars and motorcycles. Are they steered by rear wheels? Mostly not and with good reason, the steering is better done by the front wheels. In making a turn, the front mounted rudder would direct an increased water flow to one side of the keel which would increase the effectiveness (lift) of the keel - keep the boat upright , the sails would have more power, the boat less leeway and the turn executed much more quickly. In heavy seas, the forward mounted rudder would provide greater stability and control because of its beneficial redirection of water to one side of the keel. Docking and tight maneuvers would also be much easier because the bow is steered, rather than the stern. Under power, the propeller would be many times efficient. The rudder would not be blocking the thrust of the propeller nor inefficiently redirecting it. The rudder could be configured to alter the characteristics of the bow wave which would increase the hull speed and overall speed of the boat. Just like railroad tracks are the width of a horse's ass, rear mounted rudders are the result of the legacy of dry helmsman. In these modern times it's very practical to put a rudder under the bow and enjoy the increased performance benefits. Unfortunately the water deflected by the forward rudder is so turbulent that it destroys laminar flow over the keel. Likewise for the alternative arrangement, during any type of turning of the boat the keel would generate turbulent flow that would destroy laminar flow about a rudder behind it. Both generalizations may be true in some instances but not in all instances. keel has already had the benefit of laminar flow in the conventional arrangement. OzOne of the three twins I welcome you to Crackerbox Palace. |
Possibly a major flaw in sailboat design?
On Thu, 4 Dec 2008 16:23:48 -0700, "Charles Momsen"
wrote: Front rudder he http://www.cbtfco.com/ Yep, on a big big boat so flow is not efected over keel as vortices shed from the forward rudder are outside of the turning radius OzOne of the three twins I welcome you to Crackerbox Palace. |
Possibly a major flaw in sailboat design?
Ever seen a fish with forward rudder?
Philip C Bolger was the first to expiriment with the concept (at least in modern history). |
Possibly a major flaw in sailboat design?
"jlrogers±³©" wrote:
Ever seen a fish with forward rudder? Philip C Bolger was the first to expiriment with the concept *(at least in modern history). One his more interesting experiments/essays... actually he tried it twice, first time on a boat with a sharpie hull and an experimental double-luff full-batten main. This boat was very difficult to sail and was an unmitigated failure (one of the best things about Bolger is he tells what he's tried that *doesn't* work); but he thought the forward rudder had possibilities and tried it on another boat of well tried design. Fresh Breezes- Doug King |
Possibly a major flaw in sailboat design?
"Charles Momsen" wrote in message ... In contemplating sailboat design I think I have found a fundamental flaw, that when corrected should yield a great improvement in sailboat performance. The flaw is that the keel is put before the rudder. I believe this legacy continues in modern designs because of accident. The rudder rightfully belongs in front of the keel, not behind it for reasons that shall become obvious upon further reading. Firstly, think of cars and motorcycles. Are they steered by rear wheels? Mostly not and with good reason, the steering is better done by the front wheels. In making a turn, the front mounted rudder would direct an increased water flow to one side of the keel which would increase the effectiveness (lift) of the keel - keep the boat upright , the sails would have more power, the boat less leeway and the turn executed much more quickly. In heavy seas, the forward mounted rudder would provide greater stability and control because of its beneficial redirection of water to one side of the keel. Docking and tight maneuvers would also be much easier because the bow is steered, rather than the stern. Under power, the propeller would be many times efficient. The rudder would not be blocking the thrust of the propeller nor inefficiently redirecting it. The rudder could be configured to alter the characteristics of the bow wave which would increase the hull speed and overall speed of the boat. Just like railroad tracks are the width of a horse's ass, rear mounted rudders are the result of the legacy of dry helmsman. In these modern times it's very practical to put a rudder under the bow and enjoy the increased performance benefits. Sounds logical but, unfortunately, it's not. Why? Because a forward rudder is inherently unstable. How many rockets have you seen with the tailfins on the front? Space Shuttle doesn't have the rudder on the front. Airplane? No. Not even a canard airplane has a forward rudder. Fore and aft directional stability is paramount. You might be able to gain a wee bit of efficiency in steering with a forward rudder but it will always try to become an aft rudder - the more so the higher the velocity. And don't say air and water are two different things. I know that but a fluid is a fluid is a fluid and air is considered a fluid when things operate in it at sufficient velocities so air analogies are valid I hope this helps. Wilbur Hubbard |
Possibly a major flaw in sailboat design?
wrote in message ... "jlrogers±³©" wrote: Ever seen a fish with forward rudder? Philip C Bolger was the first to expiriment with the concept (at least in modern history). One his more interesting experiments/essays... actually he tried it twice, first time on a boat with a sharpie hull and an experimental double-luff full-batten main. This boat was very difficult to sail and was an unmitigated failure (one of the best things about Bolger is he tells what he's tried that *doesn't* work); but he thought the forward rudder had possibilities and tried it on another boat of well tried design. Fresh Breezes- Doug King It was tried here in 2006: http://www.mediterraneanavenue.com/F...likeButter.pdf Some benefits are mentioned. |
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