does hull design still develop?

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gjgm

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I was thinking less of larger hulls that perhaps didnt exist in the leisure market 25 years ago, but say sub 40ft. While not considering within a brand, is there anything new, or is a top hull from ten years ago, still pretty much a top hull today?
 
I can remember reading about ventilated steps on seaplane hulls nearly fifty years ago. And wasn't there a runabout (beginning with a W ?) that had chines running at 90degs to normal chines to introduce air into the hull/water interface ?

Different application, but not a new development, possibly, in the Beneteaux.
 
On a slightly different subject - I read somewhere how the shape of an airplance propellor is critical for optimum performance, yet since the Wright Brothers, props have only been improved by a few percent.

I wonder if it is the same for boat hulls & props, despited all the fancy computer aided systems around today.

MVP
 
there is a the following developments which are happeneing at the moment which are quite interesting -
- Inrizzardi is studying a new stepped hull for an Italcraft 45 sportboat with surface drives togather with Uniiversity of Rome, this hull should need minimum horsepower and obtain much better efficiceny
- the hull of the Mochi 23 Long Range is also interesting for the lower speeds and is patented
- Premiere Yachts also from Rome has also released a hull called Polivalent and patented in 2006 which can plane at low speeds about 15 knots and have stable characteristics at displacement speeds too, this hull is patented as is now also being studied for Military use
 
i remeber talking to a friend who used to race powerboart 10 years ago saying they tried the airstep. slightly less scientific by making the step by using a bit of guttering in the mound and having a lever to open and close the air flow going onto the step!

He said it was "interesting" in the early days of the heath robinson developments which resulted in a spectular roll whilst going for a mark in Table Bay!!

whilst a little older now, the wave piercing theory seems to be taking more interest, particually in commercial and military applications.
 
It might be true if you consider a propeller designed to transmit about 12 hp at speeds of up to 30 mph with a very slow-turning prop but the trick is to maintain that efficiency when shifting several hundred horsepower at just sub-sonic speeds. That's where all the development went.

Even then I'm not convinced given that man-powered flight has achieved over 20 miles at about 7 mph and a mile at about 20 mph on what must be less than one hp. I know the aircraft had a much better L/D ratio but not that much better surely?
 
Fundamentally not. I was looking at a 1960's Fairey Spearfish the other day and the variable deep V hull looked pretty much like a modern day planing hull, even down to the number and positioning of the spray rails. IMHO, planing hull design has barely moved on at all in 30 years, certainly not since Olesinski came along. OK deadrise might have increased on some hulls and refinements like stepped hulls and air injection have come along but there's been no step change in planing hull performance in that time. Any increase in efficiency has really come from lighter more powerful engines with electronically controlled fuel management.
IMHO, if you take an early Olesinski hull, for example the 1980's Princess 45, and stick 2 modern diesels in it, it won't feel a lot different in a seaway to a modern day 45 footer. Certainly, given the current economic situation and rising fuel prices, some kind of different planing hull design which moves the game along substantially is well overdue
 
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