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While I am certain that the other posts were written with the best of intentions, they could be a bit confusing. Let me see if I can provide a different explanation for you. First you must appreciate that there is no one single pitch figure for any propeller - but there are meaningful figures...

You really need to address the objective purpose for the IE (half-entrance angle) in order to develop a way to quantify it. As you can see from the thread there are as many definitions as there are perspectives. I had a (very) young designer some years ago tell me that he always puts a...

I was asked in another venue to describe what we do in Propeller School, so I thought I would post that reply here. For a quick snapshot, Propeller School is a half-day seminar that has become one of the best parts of my job. It is an informal, interactive, and fun event, where I get to drill...

An interactive seminar the day before FLIBS for those interested in the topic: Propeller School | Prior to Ft. Lauderdale International Boat Show http://hydrocompinc.com/events/propeller-school Also includes a follow-on reception and presentation about propeller inspection.

I am sure that I will regret getting involved, but hopefully I can shed some light on the subject. The orthodoxy that people hold onto is really a bit absurd... In short, all are correct and none are correct - if you try to debate the term "planing area". It is simply a matter of two different...

An interactive seminar for those interested in the topic: “Propeller School” | Victoria, BC http://hydrocompinc.com/maritechpropschool

Join us in New Orleans before the Workboat Show for a 1-day PropExpert “Best Practices” Training Course. Check out the video at: https://youtu.be/ztNGmoi7hY4 Register here: http://hydrocompinc.com/propexpertbestpractices

For those interested in the topic: http://nmpa.net/annual-convention-set-for-november-10-12-association-adds-new-feature-half-day-hydrocomp-propeller-school/

Is there any chance it is nothing more than a standing platform for some sort of work that needs to be done over the stern?

Hate to deflate the OP, but this is old news. Sander Calisal wrote a JSR paper in 2002 about much the same: http://www.ingentaconnect.com/content/sname/jsr/2002/00000046/00000003/art00006

It seems that the Wide Light project is being presented at this year's CSYS. See Chris Barry's post: http://www.boatdesign.net/forums/education/csys-2016-march-18-19-a-54984.html Don MacPherson HydroComp

Mikko: I was only looking at the CB-1 (canoe body only) case to isolate the hull from any other influences. This gives me a sense for how the calcs handled the simplest case... Don

My impressions about the heave data were from Figure 22 of the published report. It is the relative heave from static (zero speed) that is important - and the heave is negative (sinkage) across all speeds. (Trim may cause the bow to appear higher...) Don

Regarding indication of planing, in my "inference" that a hull is planing (as "definition" is too rigorous a term) the vessel first must pass the test that it's dynamic VCG is higher than static. (See post #2 in the thread.) That is not the case here. Heave is negative throughout the speed...

Well, when the hull form very closely matches the parameters of the series it should not be surprising that the predictions are close. It is when we have a hull that doesn't match a series that a higher order method is justified. In my (limited) experience, wide and shallow hulls often are...

Uli: I wonder if the correction to 15C also considered the small change in density and draft (sinkage), or was the correction solely viscous? If one assumes that the displacement was constant (regardless of water properties) at 197 kg, it seems perhaps a better comparison will be at the tank...

Uli: Does this mean that the Miles Cornwell statement about test conditions being FW at 20C is incorrect? Don MacPherson

This thread reminds me of the Star Trek episode with the white-black bi-colored race that hates their mirror-image black-white brethren. Power and torque are two sides of the same coin, and it is not at all useful to think that one is better than the other for calculations, or that one is even...

An interesting alternative to half entrance angle for seakeeping analysis is the "vertical prismatic coefficient" - particularly the CVP for the forward part of the sectional area curve. An article we wrote some years ago tells the story...

David: Thanks for the endorsement, but like anything, you do something long enough and things begin to take shape. I've always found hydrodynamic puzzles to be particularly fun to solve. I guess I'm wired to "find the signal in the noise"... Regarding the use of the demo, I am not...