Smoke Hoods and Lifejackets
Could they not design it so that the lifejackets had a smoke hood built into the back, and the lifejacket only inflated when it came into contact with water?
That way you have one pack for two purposes, and you avoid the situation of silly pax inflating their life jacket when inside the a/c.
Also, im sure i watched a prog about how lifejackets by the nature of their design swung you round so you were facing into the swell, making it that much more difficult to breathe as the waves hit you. In this situation, the smoke hood would keep the water off your face.
See? Full of good ideas me.
Matt