When reefing the main in moderate conditions on a crossing from Sicily to Sardinia about ten days ago, something went THWACK and a cloud of shrapnel and dust came out of the mast slot. The partially furled sail also unfurled itself a turn or two. Peeking into the mast inspection slot with the cover removed, we had broken the bottom of the furling foil, or so it seemed at the time. We somehow still managed to furl the sail up, carefully, with the winch handle on the mast, probably because the tack hook rotated it enough or the jagged break engaged in the top sufficiently, not sure, but we were happy about not having to drop the sail underway. Unfortunately the sharp bits chewed on the foot of the sail a bit, but it looks like the damage to the sail isn't serious.
After some despair and a few days of rest, we used a calm day at anchor to drop the sail and have a proper look at things. Good news was, the main part of the foil is intact, the break is below the tensioner screw. Even better, I have then managed to extract the broken parts through the inspection slots in the mast (bit like deconstructing a ship in a bottle). I'm also confident it can be reassembled that way, without having to unstep the mast (hooray). It'll be a fiddly job for sure though!
The tack assembly looks like it has been overloaded at some point and also has corroded where water pools in a place with no drain, from the inside out. Not sure in which order these events occurred, but I suspect corrosion first, overload of the weakened part later, final fracture now.
The part is 540-710-12 (TACK ASSY FLN RA HVY DTY) and is on back-order from Selden via SVB and will hopefully arrive in early July (fingers crossed). Meanwhile we've got plenty of time to experiment with sailing under Genoa only
Meanwhile I'm having a go at taking apart the broken tack assembly. If I can drive out the reinforcement insert, I can probably improvise a repair with what we have on board by extending the bottom connector. Might need to buy some monel rivets, but probably can find those in Olbia.
No help is needed (unless you happen to have this part laying around), just thought this may be of interest to some, as this system is very common on Bavarias. It is impossible to inspect for corrosion without removing the part and drilling out the rivets though. If you do have a newish one, I'd advise filling the area under the stainless bottom tensioner screw with sealant through the gap to avoid water sitting in there and corroding from the inside out.
Photos below: