It was about 5 minutes before our start, right after the big rain/sleet/hail squall. Close-hauled on port, we bore off to pass astern of a starboard-tack Newport 30 about 8-10 lengths away. I know I was turning a bit faster than the sails were going out, but the wind was in the 20-25 range and I had eased enough main so that control was not a problem.
BANG! The mast broke right through at the hounds, where the forestay meets the mast (about 3 feet below masthead on a Merit 25). This is the position of maximum bending moment produced by the couple between backstay and forestay, so it's not an unheard-of place for a mast to break. The jib was stalled and probably at maximum lift. Easing the main a little for the bear-off probably shifted some load from the leach of the sail to the backstay, so I can easily believe that the bending at the hounds actually increased a bit at that moment.
We looked up and at first thought the jib halyard block had failed, or the head of the jib had pulled off (the 4-year-old North kevlar #3 was up at the time, and the almost-new North 3DL main).
Then we saw the mast crumple. With the top of the mast folding back, the backstay was no longer supporting the mast against the forward pull of the forestay. But there are aft lowers that attach to the mast at the spreaders - so the top half of the remaining mast folded over forward, breaking at the spreaders, pulled forward by the forestay and jib.
So we had a mast in three pieces held together by 3DL, and a jib in the water. But the lower part of the mast (stepped on deck) raked back 45 degrees or so and stopped. I turned downwind to unload everything as much as possible, and popped open the outhaul, vang, and cunningham (all conrolled from the driver's position on my boat). Meanwhile firstname.lastname@example.org (who says she was almost late for the race because she was sending an email flame to Alan DuBoff) on the foredeck pulled the jib out of the drink, assisted by email@example.com.
At the mast, firstname.lastname@example.org couldn't figure out why the mast stub was still up. I gave the helm to email@example.com and got the wire-cutters, those small ones with the red handles they sell at West Marine. I was able to cut the port forward lower, thinking that very tight shrouds were holding the mast up, but it made no difference. Finally I spotted the boom vang. With the boom in the cockpit, even with the control lines slack the 16:1 cascade tackle tops out a some point, so the vang was tight and would not allow the angle between mast and boom to change. Once I cut the spectra vang (very easy with the wire-cutters) we were able to lower the reamains of the rig.
We couldn't get the main out of the mast or the jib out of the headfoil, so we sailed back to Berkeley as is. The Olson 30 LIQUID GAIT (I think) gave us a tow under sail for the last half mile into the marina, and we paddled the last few feet to the berth (let's hear it for having two 6-ft canoe paddles on board - the 2 HP Honda outboard was on the boat but with a broken starter cord).
It took about an hour to get the main off the mast - only one broken batten and some damage to the luff tape - which is just as well becasue if the luff has to be re-shaped to match the curve of a new mast, they might as well do it when they put a new luff tape on. No way to tell at this point in time if there was any stretch damage to the sails. Probably not, but I'll sail with them on another Merit to check them out.
So, that's the story. All things considered, there are *much* worse times and places to lose a rig. The insurance situation looks good - but nothing's for certain with insurance companies until the check is in hand.
Maybe I can borrow that Sonic 30 for 3-bridge...