Originally Posted by Merit25lovers
Traveler at center, and Boom WAY out
I don't think there's any more to it than this. Your rig is totally unbalanced this way.
The gust brought the wind aft, stalling your jib, and with no pressure on the main, and very little flow over the keel and rudder, that will spin your right around. Basically you were steering the boat with the sails.
Upwind in strong winds, everything needs to be tight. In an emergency, you can dump the mainsheet, but you can't sail that way continuously. In those conditions, I would have two reefs in the main.