The Hawk at Akro hit the ground, the top latch broke, the seat rode up the rail, fired the drogue gun bolt which then extracted the chute and the pilot. Curley ended up sitting on the ground wondering what had happened relatively unharmed.
A privately owned JP5 flying from North Weald in the late 90s had a deactivated seat - or so the owner thought! Because the seats weren't live, he never checked them and didn't notice the top latch on the RHS was dislodged. He took his brother flying and flew a slow roll. When inverted, the RHS (unlatched) rode up the rail and tripped the drouge bolt cartridge which was still installed even though the seat was allegedly 'safe'. The subsequent extraction of the pilot's brother through the hole in the canopy left the chap hanging in the harness with the QRB lodged under his chin as he hadn't connected the crotch loops when strapping in! he landed on a car in the local Tesos breaking his leg in the process.