Dozy, just personal opinion, but she must have been out of trim in yaw.
It kept wanting to turn right and did a 270 turn to the right in increments on its way down. A swept wing bird at high AOA is very sensitive to rudder input. Very insensitive or even contrary to aileron input.
Why out of trim in yaw? Probably a rigging issue. How often does someone actually check this on a flight-probably never, or almost never.