One thing about being overpowered with the spinnaker up. You have two courses of action that largely depend on your targeted course. If you are sailing deep for VMG to a downwind mark, you want to bear the boat away further downwind when you are affected by an increase in wind pressure that raises a hull. The crew should continue to maintain proper trim on the spinnaker because if the helm can get the timing right, the boat will bear away exactly as the boat tries to power up and speed up. The net result is that the boat will mostly maintain the same speed but you will be sailing a lower angle closer to the mark - your apparent wind will not change very much so you will not need to make any large trimming adjustments. The trick to staying fast is to be able to anticipate when the gust will subside and start steering the boat back up to the higher course before your speed starts to drop off. You will also find that if you can catch the remaining wind pressure just right as the windward hull starts to drop back down to the water, that you will get a short little boost in speed.

The second method of depowering, you will use if you are already trying to sail as high as possible to reach a mark you have overstood or, again, distance racing. Use the traveler to dump mainsail power - don't touch the mainsheet, just start easing the travler before you try and turn the boat downwind. You will find that it takes a pretty large movement of the traveler to have an affect. As with sailing upwind, downhaul on the mainsail can have a pretty big effect on power even with the spinnaker up and we use it as well if we are trying to reach up high over a long distance.

If you find yourself suddenly overpowered such that you cannot react to it (aka "shooting the mine") I believe leaving the spinnaker sheeted can help pull you back from the depths. Most importantly, however, as the boat quickly decelerates from the sudden increase of liquid resistance, the people-weight must remain at the back of the boat to have any chance of recovery. If you suspect you are in conditions that may precipitate such a condition, stay planted and both the helm and the crew should have a very firm grip on the boat. While driving in these conditions, I usually let the hiking stick skim behind the boat while I hold directly onto the cross bar in a nealing position, facing forward with my windward hand holding firmly onto the side lacing of the trampoline with the traveler line in that same hand. Occasionally in this circumstance, as the boat goes in and the rudders come clear of the water, the boat will want to turn and round up (aka "deathroll"). In this circumstance, the crew needs to release the spinnaker sheet quickly and the traveler needs to be released as well.

Next lesson; managing power and speed while sailing under spinnaker in significant wave action....