posted 06-24-2002 10:48 AM ET (US)
Gentlemen:I have been reading this site for a long time and never felt the need to post my opinions. Facts, on the other hand need to be conveyed rather than conjecture.
Planing hulls are always a compromise.
Displacement (what you call weight), Center of Gravity, Center of Bouyancy, Metacenter, etc. are all design parameters that influence how a hull performs at any given speed. If for the sake of this discussion you must choose to focus on displacement as your "measure of quality" then I suggest that how one distributes the weight of the materials is much more important. For example, would you design a sailboat with lead decks or a lead keel. Both would have the same displacement but only one keeps the sailor breathing air.
In planing hulls, we design for hydrodynamic lift, seakindliness, cost, and funtionality. Since these hulls are usually for pleasure boaters, cost is the number one factor.
In the Louis Vitton Cup (formally America's Cup), the sailboats utilize only the most cutting edge materials- multiaxial glasses, carbon fiber, superior strength epoxy resins, titanium, etc. Cost is not as much a factor as is putting the majority of their allowable weight (they are restricted by an equation which includes weight) in areas to help improve their performance.
With pleasure boats, s-glass vs. e-glass vs. kevlar are all glass choices as is polyester vs. vinylester vs. epoxy resins. Do we hand-lay, vacuum bag, thermal cure? All these choices are for strength versus weight.
The reason I mention all of this is that I could design a very light but strong, high tech stepped hull which could blow the doors off all existing pleasure boats today---but no one could afford it. For each decision in hull design or material choice, a compromise is made by the manufacturer. Your decision is made through your purchase in which you too, made a compromise...think about it.