VH-XXX - well I would have thought then that they are not much use to help keep the aircraft afloat and allow people to get out if that is the case.
I would have thought that they will keep the aircraft upright and afloat for some decent period until/if they loose pressure - but I am only speculating here - but they seem a waste of space if in fact they fail to keep the aircraft upright and floating for some decent period of time. If they don't do that why have them in the first place?
Thanks
Alex Ford