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What is the Crouch hull factor for a 1985 Outrage 25 notched transom?

mwk4619 wrote:What is the Crouch hull factor for a 1985 Outrage 25 notched transom?

A figure 180 is a conservative number to begin estimatng the speed potential of the OUTRAGE 25 hull with the Crouch method. At the highest possible boat speeds (with maximum power or even higher than rated power) the much reduced wetted surface of the hull MAY result in the hull coefficient rising to 190--or perhaps even higher if the hull speed gets really crazy, like over 60-MPH.

I use the coefficient of 180 for the typical moderate V-hull found in the classic hulls, and 190 to 200 for the rounded bottom hulls. Note that the odd-numbered lengths are typically rounded bottom hulls (11, 13, 15, 17, 21) and the even numbered hulls are typically moderate V-bottom (18, 20, 22, 24). But when the marketing department decided to change the 24 to be a 25, that broke the rule.

Thanks Jim.

[The Crouch coefficient that I calculated based on] actual performance [of my OUTRAGE 25 hull] came to a little over 200

[Pointed to another adaptation of the Crouch method]

mwk4619 wrote:[Pointed to another adaptation of the Crouch method]

As far as I know, my implementation of the Crouch method of boat speed prediction based on power, weight, and hull coefficient was the first calculator of its type on the internet.

The Crouch Method of estimating the speed of a moderate-speed planing monohull boat was first mentioned on continuousWave back in 2001, or 23-years ago, and about five years later an on-line calculator was created (by me) to aid in making those calculations. Here is a link to the announcement of the Crouch's Calculator on continuousWave in April 2006, or more than 18-years-ago.

http://continuouswave.com/ubb/Forum4/HTML/004403.html

The Crouch's Calculator took a short hiatus when I had to change hosting arrangements, as the new host would not permit the particular method used in the calculator (based on possible cgi-bin exploits). So I reinvented the calculator in a new implementation in 2017.