Same thing happened to me a few years ago, just finished working on a Maserati 450s and took it out for a road test, going up the road I forgot about a big bump, car left the ground and when it landed the dry system went off, now a 450s is an open cockpit deal so you can just imagine what this looked like, at the same time I thought I had blown the motor and fully expected to be working to pay it off for the rest of my life!

Halon is banned in extinguisher systems in the U.K. by the way