Crouch Constant

[Timm]

Sorry Mike, I don't have a lot of sense (ie.. I actually try to make a living designing boats), but I do know a good deal when it comes along! I don't know much about programming, so I tend to write alot of spreadsheets for various and sundry things. I have wanted to write one for resistance myself, but have yet to find the time.

MMD, I'll definitely post it if we can get it published. The publishing rights belong to Westlawn, so we have to work with them. They may be working with another publisher. We do have the rights for Common Sense of Yacht Design by L. Francis Herreshoff. Hopefully we'll get that one out next year. Used copies of that book sell for hundreds of dollars, so we should be able to sell a few thousand of them.

[Jimboat]

Check out the design info in the Tunnel Boat Design book. It's not as simple as an easy formula for all planing hulls, but it is very accurate for high performance planing powerboats, particularly powercats and tunnel boats.

Also have software that does the same thing (only faster).

[yipster]

still got to get some of your books and software one of these day's jimboat.
meanwhile in a quik search on the net i found this handy calculator

a list of specs on various boats and C constants would indeed stil be very nice...

[Jimboat]

Yipster - thanks for good words. Call or email anytime to talk boat design, or check out STBD book or TBDP software. Happy to help anytime!

[sharpii2]

I think it would be very usefull to have 'C' constants for diferent bottom types. At least for the two most extreme, i.e. The flat at transom, 'variable deadrise' aka 'warped bottom', and the straight keeled deep 'V'd 'constant deadrise' aka 'deep 'V'. This would be useful and instructive for designer and client alike.

The data on these two extremes could be used to bracket a proposed designs hull type which will usually fall somewhere in between these two extremes.

Data that would also be useful would be 'minimum hp per ton to plane' for each of these two exteme types.

Bob