Stein,

In 12-18 knots, you need to really move to the back of the boat (both you and your crew) as you make the transition from upwind to downwind. If you do it right, you can fly the hull through the transition and put 100 yards on the next boat. As you bear away, have both crew move to as close to the rear beam as possible. As the speed picks up, you really should not ease your sails much at all as the apparent wind will stay forward. The control to release during this transition is the mast rotation. Release it to 80-90 degrees and you will feel the boat stay powered as you steer down. Bleed down with the speed as much as you can before you make the move to set the chute. We're talking about 5-10 seconds of sailing. Once you are downwind ease the traveller about half down but keep some mainsheet tension to act as a backstay as you hoist and fill the chute. Reset the traveller once the chute is flying and the boat is up to speed.

In over 18 knots, it is difficult to do this as there can be simply too much power. What you can do is come off the wire as you prepare for the turn, both crew come all the way aft, release the traveller to full ease, ease at least 12"-18" of mainsheet tension, and then keep the jib trimmed properly as you turn down. The weight shift aft and releasing of the traveller should allow you to make a safe turn down.

Most pictures I have seen of crews pitchpoling as they turn from upwind to downwind in both moderate and heavy air have been a result of not being far enough aft and keeping the mainsail too powered during the transition.

Also keep in mind that if you stall the top of the mainsail along with the chute in heavy air downwind, you are in the "death zone" that can result in a fast pitchpole. Keep the flow working on both sails. Drop your traveller slightly (maybe 6") to bleed some power if you feel the need. This should allow you to work with around 6" of mainsheet tension to keep the top of the mainsail working and prevent it from stalling. Your crew has to also trim the spinnaker in synch with you (i.e. if you turn down, he must ease to prevent a stall).

Good luck.

Bob Hodges
A-Class USA 230
ex F-18HT driver