Boom Vang

If the Hobie 12 sail is loose-footed, not attached contiguously along the boom, what is a boom vang’s purpose on a Hobie 12?
Thanks,
Denis

Based only on my other loose footed boats, I can say the vang holds the boom down when the mainsheet no longer clamps it down near centerline. Otherwise if you let out the mainsheet, the boom can go up as well as out and the slack sail wants to fold like a taco shell. You probably have an outhaul to make the foot less loose. I think you don't have a cunningham which can tighten the belly of even a loose footed sail.

I happen to be watching a short video below tuning these issues but on a bigger boat. Also if you are unfamiliar with unstayed masts where the boom can swing even a bit forward of the mast, beware of a "death roll". The boat can suddenly roll to the opposite side of the boom, where you are probably sitting as a counterweight. Knowledge of borderline trim issues will let you know when to stop counterweighting as 2nd video failed to:

Thank you, makes all sense now.
Denis

The boom vang holds the clew (back corner) of the mainsail down. It allows you to control mainsail shape, so that when you ease the mainsheet, the boom travels out rather than up. This keeps the sail flat when it’s let out. It works in much the same way as the mainsheet/traveler work together on a beachcat.

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