There was a thread on here a long time ago about a guy that made a CO2 cartridge with balloon
... you can buy one. Just search for: Secumar Auto Inflation Anti-Inversion Mast Float
Somehow not very common. I've never seen a boat equipped with it. Propably because getting a beach cat out of the 100% turtle position by manpower is not so difficult, as far as the boat is not too wide like Tornado, H21, or others.
That "airbag-recovery" could work on any boat I guess.
