Estimated sheet and block loads for a J/37, rounded up to the next 
whole number.  (Source: boat yard computer database.)

100% headsail = 378.6 sq. feet
135%              = 511.1
150%              = 567.9
 
Headsail     Windspeed         Est load (lbs)
 
SHEET LOADS
 
100%            30                        1467
100%            35                        1999
100%            40                        2611
 
135%            20                          882
135%            25                        1375
135%            30                        1983
 
150%              5                           62
150%            10                          245
150%            15                          551
150%            20                          980
 
LEAD BLOCK LOADS
 
#3 (100%?)    30                        1924
#3 (100%?)    35                        2619
#3 (100%?)    40                        3421
 
#1 (150%?)      6                            67
#1 (150%?)    12                          265
#1 (150%?)    18                          595
#1 (150%?)    20                          735
#1 (150%?)    25                        1148
 
END BOOM LOAD                     2706
 
MAX HEADSAIL TURNING BLOCK LOAD
 
  60 deg. turn                             1999
  90 deg. turn                             2819
135 deg. turn                             3678
180 deg. turn                             3998
 
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