Pi: Nice diagram. I think I see what you're getting at. You're right about any set of axes being valid--I've just found that referring it to...
PI: I recently went through some painful 'thinking' about lift and drag, but came to very different conclusions. These are the simple examples...
messabout: Thanks for sharing your towing results--what are the units for the S/L ratios you mention? Knots/ft? And have you scaled those...
Sigurd: The drawing was done on SolidWorks, a mechanical CAD package. It doesn't do hulls or ropes very well (that I know of) but it's great for...
Back to hull drag: I've been thinking more about the analogy that I mentioned earlier in the thread (and no-one commented on--perhaps it's dumb?)...
Thanks for the comments. I'm sorry that the presentation doesn't go into more detail about how the rig works; I will add some more description...
I've been hesitating to put the design out there, but here it is. I've attached an explanatory powerpoint presentation, plus a short video clip...
If anyone has the means and inclination to do similar tow testing on other small hulls, I would be very interested in hearing your results. I am...
I did some "tank testing" yesterday; basically pulling things behind a little 14' aluminum 10hp runabout, and leaning out the front of said...
Jon; can you reveal any details about the superventilating foil? I would be very interested in the shape, and how well it transitions from low...
Hansen: I've looked at the Hoot website; do you have links to see the rest, or is there a Hansen Design website? Thanks, Matt
That makes sense, below planing speeds; the wavemaking drag curve is exponential while the skin drag is linear. So at the low end of the...
Doug H.: You show the front of the boom attaching to the mast well above the clew. If the front were lower (boom more horizontal), then there...
Sal's Dad: Yes, I think I'll be doing some towing. I do hope the forces will be a lot less than 3000 lbs! PI Design: The spreadsheet will be...
Thank you all for your help; it does seem that the hull shape becomes less important at higher speeds, with the wave-making drag decreasing as the...
Clarification I am most interested in resistance at planing speeds, 15 knots and up. Has anyone towed a Laser behind a speedboat?
Does anyone have reasonably accurate (+/- 50% would be a start) formulae for calculating the hull drag (ignoring keel) both on- and off-plane? Or...