Calculated Genoa Sheet Loadings
Sail Area Load (lbs.) for Apparent Wind (Knots)
Square Feet 5 10 15 20 25 30 35 40 45 50 55 60
 Furling Genoa      480        52      207      465      827   1,292   1,860   2,532   3,307    4,186    5,168    6,253    7,441
 Genoa Part Furled (100%)      385        41      166      373      664   1,037   1,493   2,033   2,655    3,360    4,148    5,020    5,974
 Working Staysail      160        17        69      155      276      431      621      845   1,103    1,396    1,724    2,086    2,483
 Storm Staysail      115        12        50      112      198      310      446      607      793    1,004    1,239    1,499    1,784
 Asym. Cr. Spinnaker   1,295      140      558   1,256   2,233   3,488   5,023   6,837   8,930  11,302  13,954  16,884  20,093
 Genoa Sheet Load (lbs.) = SA * V**2 * 0.00431 
 Formula Source: Harken (http://www.harken.com/blocks/loads.pdf)
Mainsail Dimensions 100% 75% 50% 28%
P. Foot length of Main in feet 45.3 39.3 32.1 24.0
Enter Sails and Sail Area for your boat.
Enter Mainsail Dimensions for your boat.
You may modify any cell with yellow background.
E. Luff Length of Main in feet 14.6 12.6 10.3 7.7
X. Distance from Aft end of boom to mainsheet attachment point in feet 0.0 -2.0 -4.3 -6.9
Calculated Main Sheet Loadings
Sail Area as % of Main Load (lbs.) for Apparent Wind (Knots)
5 10 15 20 25 30 35 40 45 50 55 60
 Mainsail 100%        68      272      611   1,086   1,697   2,444   3,326   4,344    5,498    6,788    8,213    9,774
 Mainsail 1st Reef 75%        44      176      397      705   1,102   1,587   2,160   2,822    3,571    4,409    5,335    6,349
 Mainsail 2nd Reef 50%        24        96      217      385      602      867   1,180   1,542    1,951    2,409    2,915    3,469
 Storm Trysail / Third Reef 28%     10.1     40.2     90.5   160.8   251.3   361.8   492.5      643       814    1,005    1,216    1,447
 Main Sheet Load (lbs) = E**2 * P**2 * 0.00431 * V**2 /(sqrt(P**2 + E**2) * (E - X))
 Formula Source: Harken (http://www.harken.com/blocks/loads.pdf)
 This formula is not so well accepted as the Genoa Sheet Loadings