Holiday on a sail boat - October 1981

I've titled this photo, "Holiday on a sail boat", but in truth I'm not really sure what is going on here. The main couple in the photo seem to be climbing onto the table in front of them whilst others site and watch. The woman is holding onto what I assume is a sail, but I don't know if they are about to climb up the mast or try to limbo under it.

Taken on Kodachrome in October 1981.