Spiral is a very controversial subject.
We used on purpose for this video an EN certified glider (Spiruline EZ XXL got an A for the spiral exit test- self exiting in less than 720°).
This video is here to keep you aware of what gliders can do and that you should learn how to react.
Education and training is the key for your safety. Practice under supervision in a safe environment.
Fly safe!

Check out the video HERE!

(please note, it´s just a hint to make you think about, no general solution)