Gennaker: Sits on a furler
and is easy to manage when shorthanded. Will fly at perhaps 20 degrees higher into wind
( say up to 65-70 degrees AWA - esp in light air) than an ASI. Less effective when on a deep reach and useless when running at AWA of 150 or more. Probably the better choice is you are always short handed and don't want to sail deep down wind optimally.
ASI: see above. Can use a furler
, but generally used with a sock that requires at least one other experienced hands to get it down. Can be used with the wind a little forward of the beam but best on a reach of a deep reach and being larger will serve well in these circumstances. Will struggle deep down wind, but OK up to 55-160 AWA.
SPI: You'll need a good mate to douse (like the ASI). Optimal for Deep down wind. Always better to sail a little off DDW regardless. Better for the long down wind passage
. Correct sizing for you purpose, likely wind range and crew skill become important.
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