Not uncommon to see these guys vault into the air, I probably see them at least once every two trips when I launch from Crandon Park in Biscayne Bay. I've even seen a manta about 6 feet across vault out of the water about 5 feet high, almost come to a pause, then circle down to nose dive back into the water. Most amazing thing I've seen out there yet. I think it's common enough that every once in a blue moon, one's liable to end up in a boat. Unfortunately, she probably wigged, slipped, fell on the stinger and hit her head at the same time. Probably could've happened to anyone.