The Comfortable Pocket Yacht

Flicka Sailing

Trailer Voyages
Trailer Sailing Sailboat Math
 Flicka Voyages References

Site Update List

Flicka Sailing

Selection Criteria
Short List
LED Cabin Lighting 
Water Supply
SSB Radio
Diesel Electric
Self Steering
Solar Wind's History


This page duplicates the formulas from the calculations page but allows for user input implemented as a Java Script form. The form does not have all the required error checking so if you see a "NaN" it means that there was a non numeric value detected.  Remove any commas or spaces in the input fields to fix this.  The page was designed with Microsoft Front Page 2000 to work with Internet Explorer 4.0 but should work with other most browsers that support scripts.

To use the calculator, select a boat from the list or use "Custom" to enter your own values from scratch.  Even with a list selection, you can change any of the values to suit your own requirements.  When you have set all the values, click the "Calculate Values" button to see the results.    I will be expanding the selection list and type of calculations supported  as my interests or user questions dictate.  The formulas used in the calculations are published on the main calculation page.

For Questions, Comments, or Problems with this calculator script
please send e-mail to: Jobst Vandrey - If you are reporting a problem, please include what Browser software you are using and what data you had entered into the information fields.  I would like to get as many different Trailer Sailboats as possible available from the selection list so I would appreciate it if users would  eMail me the specifications for boats not yet mentioned.  I need values for Empty Displacement, Water Line Length, Beam, and either total sail area or distinct areas for the Jib and Main in order to enter a new boat on the list.  Updates to the list will be made frequently.

Sailboat Performance Calculator

[FrontPage Save Results Component]

Select a Boat from this list and then click the associated button to initialize the form - Choose Custom if you want to enter your own values or you can modify any of the values from the initial selection

Enter the Cruising Displacement in pounds.  Include the weight of the boat, equipment, crew, and beer (500 pounds is added to the manufacturer's listed empty displacement if you use the list above).

Enter the Water Line Length.  Use decimals rather than feet and inches - instead of 16 feet 4 inches, enter 16.33

Enter the sailboat's beam in feet.  Use decimals rather than feet and inches.

Enter the Horsepower of the engine (outboard or inboard).  Decimals are permitted - 3.5 etc.

Enter the Thrust of the electric motor
Pounds of Thrust

Enter the area of your main sail in square feet (you can also enter the area of your entire sail complement here and leave the Jib data blank)
Square Feet

Enter the area of your normal jib sail in square feet
Square Feet

The displacement  to length value (D/L) calculated to be Lower numbers are found on racing boats: Light Racing Multihull (40 - 50), Ultralight Ocean Racing monohull (60 - 100), Light Cruising Auxiliary (200 - 250), Average Cruising Auxiliary (250 - 300), Heavy Cruising Auxiliary (350 - 400)

The sail area to displacement ratio (SA/D) calculated to be Higher numbers are found on racing boats: Motorsailer (13 - 14), Offshore Cruiser (15-16), Coastal Cruiser (16 - 17), Racing Boats (17 - 19), Ultralight Racers and Daysailers (over 20).

The capsize screening ratio is calculated to be Ratios below two are suggested for offshore cruising.   This number is perhaps the most controversial ratio presented here.  It's purpose is as a guide since there are many factors in offshore sailboat design and this ratio is only one consideration.

This page was last updated:  07/31/02 06:03:16 PM


Copyright © 1999-2002 Jobst Vandrey

Reload The Home Page For This Site