Helping to keep Sirona on her feet is a water ballast system of 450 gallons of potable water per side, the boat's rated water capacity. In light conditions or when you're short-tacking a channel, pump half the total into each tank. As the wind increases and you settle onto a tack, empty the leeward tank into the windward tank. According to ship's instruments, we didn't have winds of more than 13 knots, and with full sail set, Sirona felt reassuringly stiff without shifting ballast. A retractable stainless-steel keel with a ballast bulb at the tip adds to the stiffness. Down, it draws 11 feet, 6 inches; retracting it whacks 5 feet off the draft. This keel is meant to be all the way down or all the way up, and it requires a few minutes to complete a full one-way trip. A power takeoff from the generator runs the hydraulic pump that does the work, and the operation is barely audible from on deck. The retracted keel fits into a trunk that spans from the bilge to the coach roof, adding to the boat's structural integrity. Tripp's office computer-tested the boat running aground with enough force to bury half the foredeck, then engineered the structure in way of the keel to handle the loads.