wow, some of these falls sound terrifying!
My worst fall from an injury point of view was about 3 years ago when I was trying out a new riding club. For several weeks I had been begging the instructor to let me have a go on one of the horses there, a superb black selle francais gelding. Now I had ridden tons of horses more challenging than him, but none of them had been the type of horse I liked, they were all TB's and other skinny little things rather than muscled warmbloods. The instructor finally let me ride him, it had taken her a while to find a space for me to ride him since he was really popular. Then I discovered that it wasn't a normal lesson, but only once I was tacked up and waiting on 17.1hh of jumper and they all turned up on shetlands, welshes and other small ponies. Isntead of a normal lesson we were doing 'pony games' and one of the things they asked me to do was to lie down, with my head on the horse's bottom, my feet on his shoulders and canter. I told them if I did I would fall off, they didn't listen, the horse, bless him, sensed that I was uncomfortable with the exercise and refused to canter, so the instructor slapped him with a whip as we went past. Cue massive buck and rider flying through the air. I landed on my neck, result three cracked vertebrae and no riding for 3 months.
I never went back there.
My worst fall in terms of possibility of getting hurt was at a competition however. It was the first time I had competed in about 2 years so I was really nervous and had only entered a clear round class. Whilst warming up, another girl had been having terrible trouble with a young anglo-arab mare that kept tanking off over jumps. A guy that hangs around the stables a lot and calls himself a 'trainer' dragged her off the mare, jumped on, no hat or anything, he then proceeded to gallop around the arena full speed, drumming on the horse with his crop.
Meanwhile I tried to get on with warming up Sparky, who was of course being his usual Grand-Prix-warmblood-mini-me self. As I went to go over an oxer, stupid guy on the mare cut straight in front of me to go over first (I was maybe two strides from the jump). The mare frog-hopped it and bucked her back legs as she went over, Sparky, who was mere moments from take-off, slammed on the brakes and stopped in a way that most professional reiners would be proud of. I flew and landed arm chair style in the oxer, which stayed upright.
Loyal as a house-cat, Sparky abandoned me and bombed off to the side.
Sounds pretty comic right? Rider at ease on the jump, horse leaving at high speed in the opposite direction, but this is where it gets dangerous. The b****** on the horse was still galloping around and obviously was so aware of his surroundings that he didn't even notice me, draped over a jump, because he came round and headed for the jump, at the last second I managed to slip between the bars, which was just as well, because missy mare hit the top pole, exactly where my head had been and threw it off the jump. The guy then turned round, saw me under the jump and had a go at me, saying I might have put the horse off jumping! He didn't care that he could have killed me! Last time I checked the code for a rider falling off is that all horses stop moving at check they're not hurt, not jump straight over them when they're lying winded on the obstacle!