Randy Browning of sailboatdata.com here.
The site certainly has flaws. (besides cosmetic and interface issues which are both admittedly terrible.)
Criticism has also been made, for example about naming conventions, which I'd rather not go into right now.
However, I am EXTREMELY meticulous about the accuracy of the numbers.
(I get about 10 Emails a day about measurements of different yachts, much of which proves to be inaccurate.)
RE: SAIL AREA
The presence of 2 numbers for sail area is INTENTIONAL as well as the fact that they sometimes conflict. (There are actually sometimes 3 sail area #s.)
The following decision has been made several years ago and remains in place until a more sophisticated database structure could be introduced: Possibly something more akin to an IRC meas. cert.
IF-
VERIFIABLE rig dimensions are known, I have made a calculation using the traditional trigonometric method that have been used by designers and handicappers for almost 100 years. (I, J,P,etc) Even though every manufacturer has a different way of measuring sail area, this is currently the best way for people to make a comparisons between traditionally rigged boats (despite it's flaws)
IF-
a reliable source for these numbers is NOT available, none of these fields even appear, including the one for calculated tot. SA.
IF-
no OTHER SA number is available (OTHER than rig dimensions), the total sa calculation is placed BOTH at the top AND bottom and this number is used in the other dynamically generated calculations such a SA/Disp. etc.
IF-
ANOTHER TOTAL SA number IS available from the designer or manufacturer, (the results from a calculation other than the trad. trig.,)
THAT number appears in the field at the top (SA) but NOT at the bottom.
IF-
these numbers conflict, the SA number at the top is used in the other aforementioned hull calculations.
(I'm leaving out a few other decisions that have to be dynamically made in the code not worth mentioning)
The CALCULATED sail area # is usually completely IRRELEVANT for multi-hulls, dinghies, really light weight craft and extreme rig abnormalities.
In these cases, the published sail area numbers are the only ones used and are entered manually. Total SA appears in the field at the top and more detailed measurements appear in the NOTES: section.(if available).
So for Sail AREA, that's the logic used. It's not great.
Also, I don't mind criticism, especially if it contains a positive suggestion.
Regards,
Randy Browning
Norwalk, CT USA
sailboatdata.com