The invention relates to an air cushion protection system, or airbag, for users of motor vehicles having no survival cell. The present invention aims to provide an airbag protection system which is appropriate for the problems associated with vehicles having no survival cell and which improves the level of protection for users. To this end, a protection airbag intended to take the form of a piece of trim when it is inflated is provided, comprising at least one jacket (70) consisting of an outer surface (70a) and an inner surface (70b). The outer surface (70a) and inner surface (70b) are connected by a plurality of linking strips (76), two successive linking strips (76) defining between them an outer portion (78a) and an inner portion (78b) facing one another, the inner portion (78b) having a lower surface than the facing outer portion such that, when the jacket (70) is inflated, the airbag has curved parts which mould themselves to the shape of the human body.