[pgarner]

there is sense it like walking down the street and someone runs right into you. you will end up hurt no matter what

that is the idea of the airbag it inflates so quickly then startes to deflate so that when you hit it, its already been fully inflated so you are in theroy hitting something soft.
downside is if your sitting to close to the wheel of the wheel is pointed to your chest its going to hurt and if you have chest / heart problems you could be in a lot of trouble