A
Jib Top (Topper) is a reaching headsail with the foot cut very high, used when the
boat is heeled over a little, but not pointing as high as it can into the
wind, and powering through waves.
They have the same LP measurement as the No. 1 genoas, but is high-clewed and fuller in shape, so the
power in the sail is carried higher and further aft.
Jib Tops are great
sails to use in the range of about 55 to 75 degrees of apparent
wind, but are actually less effective than the
genoa in breeze less than about 10 to 12 knots.
At higher wind speeds, they can be carried effectively at broader angles until the
spinnaker becomes the faster sail.