When falling backwards surfaces react opposite, where are you holding them? Maybee this is why.
Not in my case anyway...
I'm using no aileron input in the tailslide, just letting it roll as it wants. There is something else going on to cause that right rotation. It can be quite violent and start quickly. Most of the time it's too much for me to keep up with, because I'm so used to watching it roll left and when it suddenly switches to the right I'm not ready for it.
Bill