I just wanted to reply to the bad driving comment.
My mare has had loading issues since day one of knowing her as a 3year old even before my buying her. This new problem of flying out backwards has nothing to do with my driving! I know very well first hand that she is a bad loader and since having my own box have driven many a motorist mad by how carefully I deliberately drive to make sure she has no excuse on my behalf not to go on again!!!!
This new problem of her reversing out at will is just another one of her issues. My horsebox (lorry) has a rear ramp and the horses are forward facing. The only way out is to back out, or to as she prefers widen the partitions on each side and allow her to gently turn around and come out forwards, which she has done happily for 2years (once on of course! Lol) There is nothing behind her to prevent her from reversing out once untied at the front, and as there are not rear bars or anything other than the ramp to stop her like there are on so many trailers, she is at will to do so. Although even if she were tied I worry she would simply break away.
Also can I add if a horse had had a bad trip/ride in a horsebox surely they would show signs of distress, I.e. Sweating, blowing, struggling to stand up, panic etc etc etc. She does none of this. We have a window from the cab through to the back and she never does anything that shows a slight bit of worry. In fact she loves munching on her net and looking out of the window! I have also had a friend travel in the back with her and she to said how relaxed she was, never struggling to corner with the box or struggling to keep her balance! My friend also commented on how well sprung the back was as she felt hardly any movement in the back compared to when she is sat upfront with me.
I just wanted to make sure that was clear! Sorry if I sound blunt! But I have done as much as I can to make my girl load well consistantly and sometimes she will for weeks on end and then just when you want to go somewhere or better want to leave after a super tiering day at a competition she simply wont have it! It is that inconsistant!