I just don't understand this. Even if the seatbelt emergency locking mechanism comes into play at the moment of impact, wouldn't the force alone pull the belt out of the belt path of the restraint? :scratcheshead:
We don't know that. I happen to think there's a decent chance it wouldn't, personally, although of course I have zero true evidence to back it up.
I'm thinking there is a decent chance the male part of the buckle might, for example, get hung up on the shell and NOt get pulled back through the beltpath. Haven't you ever unbuckled the seat belt to uninstall a seat, and you're yanking on teh seatbelt, but the buckle gets hung up and doesn't come stright back through the beltpath? So you ave to grab it and feed it through part way, and then pull it out the other side?
Or...we don'tknow..maybe it wuold pull straight through. Maybe it would get huing up on the shell somehow and the force would rip the shell to pieces.
Heck..the seat belt failed prior to the belt lokcing mechanism kicking in, or if the seatbelt were accidentally unbuckled prior to a crsh, perios, then there might not eve BE enough force on the belt *TO* lock it, depending on the type of retractor used.
Regardless, in the scenarios I can envision in my head, I see an unbuckle harnessed seat without tether swinging towards the shoulder belt, since it would remain inside the beltpath for at lat s a short time, so essentially, the seat swings out towards the door/window, basically smashing the kids face into the side window(assuming a frontal impact). Not a cool picture, to behonest, but stil probably better than being ejected, and really a harnessed seast isn't going to fit through most windows by height, so the seat should stay in the vehicle.
There are just way, way too many variables to have any idea what would truly happen.
as to the ijury aspect...yep, i think having a harnessed seat bouncing around the vehicle as a giant projectile would be hugely dangrous to the other passengers. You would absolutely be trading some measure of safety for the person IN the seat for a reduction in safety to other people in the car.
again, obviously no way to know for certain which woudl be the "better" choice for any given crash. Optimally, all occupants would remain restrained during a crash, of course.