Last Update:Wed, Oct 10, 2001 (659 boats)
Carl's Sailing Calculator
Go to http://www.image-ination.com/sailcalc.html for the most recent update!
Carl's: WaterLogged
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(the right way)
About My Boat Compare Boats Search Database Mine Database 0ptimizer Prop Sizer

Enter: Water line length in feet. Example 30.25 Enter: Length Over All in feet. Example 34.25 Enter: Displacement in pounds. Example 11000 Enter: Beam in feet. Example 11.9 Enter: Sail area in square feet. Example 582
OUTPUT
Sailing Category: Capsize Ratio:

Hull Speed in knots

Sail Area/Displacement

Displacement/LWL

Length Water Line/Beam

Motion Comfort
Click on Any of the Output Fields Above to Obtain a Description
Obtain information on your boat HERE
If you would like to mail the results to yourself or someone else, fill out the form below. Enter the destination address in the email field and then press 'Mail It'. If your browser does not support the 'mailto' form action go here.
Your Name: Boat Type: Boat Name:
Email:
You can compare your boat with other boats by clicking on the boat you want for a comparison on the right. Be sure that you have entered your Boat Type above! Other boats will be added to the list. If you will mail your results to me, by entering my address (Carl@image-ination.com ) in the email field above, I will add your boat to the list.

You can compare two boats already listed here by first clicking on the one boat in the list on the left and then clicking on the second boat in the list on the right.


Please note that all data included here was entered by users like you, I do not check their entries so I cannot warrant their accuracy.




You can find all listed boats 'less than' or 'greater than' any selected value in any category by entering a number in the appropriate box and pressing the '<' or '>' button. The results will be listed in the text box below.
You can chain your searches one level deep by clicking the following checkbox after doing your first search. For example, having found all the boats with motion comfort factor greater than 25, you can find all of those with a hull speed greater than 8.


Search these results only. Reload
Capsize Ratio Hull Speed SA/Displacement Displacement/LWL LWL/Beam Motion Comfort






Searched For:




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This database comtains figures of merit supplied by users of this tool. The original data, LWL, Sail Area etc., is not in the database. However it is reverse calculated here from the figures of merit. The chance of round-off error does exist. Generally it should be negligible and sometimes zero, but it can be up to about 2 %. LOA and Displacement are the most sensitive to this.I have detected errors up to 4% in these areas. If you detect an error greater than this, the chances are it was originally entered incorrectly. Please notify me of the correct value(s).

Enter Boat name then
the click
LWL Displacement Sail Area Beam LOA





To use this feature you need a 4.0 level browser.

You can find your 'ideal' boat by doing a weighted search. For example, you can search for the boat that has the highest combined normalized scores in 'Motion Comfort' and 'Sail Area/Displacement' giving one a 60% weight and the other 40%, or whatever! You can also do low searches, for example, you can search for the boat that has the highest normalized score in 'Motion Comfort' and the lowest normalized score in 'Capsize Ratio' giving one a 30% weight and the other 70%, or whatever. A 'low' search is done by finding the highest score of the reciprocal of the quantity. Thus a Capsize Ratio of 1.5 is turned into a rating of .67 which out ranks a Capsize ratio of 2.0 which would have a translated value of .5. The results (the top three boats, their scores and the average score for all boats) are reported in the text area below. (This may take awhile!)
Minimum Length: | Maximum Length: | RELOAD
Capsize Ratio Hull Speed SA/Disp Disp/LWL LWL/Beam Motion Comfort
Weights:
Search Direction:





RESULTS:

Prop Sizing and More

The material here is taken from an article by Dave Gerr NA in Sail (February 2001. pp. 81-84) entitled Sailing Screws. To really understand the numbers calculated below you should consult this article or his book Propeller Handbook. A note on the Maximum Sailing Speed calculated below:

This is also from Gerr's work. He has determined that the classic formula for Hull Speed ( 1.34Sqrt(LWL) ) does not always apply, the 1.34 is not a constant, leading to, in some cases, much higher speeds. However, Gerr observes:

"For instance, a boat with a DL or 80 might have a SL multiplier of 2.11, but it couldn't achieve that speed under sail unless it had not just sufficient sail area, but the stability to stand up to such a sail area in the wind strengths needed to deliver the required power. Not an easy task!"

The maximum speed under motor power calculated below depends on the ratio of 'weight' to 'horsepower'. The weight of a given boat does not directly appear in the database and is reverse calculated from the 'figures of merit' which can lead to a round off error of generally 1-2 % but errors of up to 4% have been detected in some cases.

Boat Name:
(Required)
The Name as in the Sail Calculator
(Case insensitive)
Horsepower(bhp):
(Required)
Prop Type:
(Required)
Classic Hull Speed: Knots Gerr's SL formula: Knots
(Maximum Speed Under Sail)
Also From Gerr: Knots
(Maximum Speed Under Motor)
Optimum Prop Diameter: Inches New RPM: