A passive restraint system in an aircraft utilizing a seat structure of the aircraft to store a source of pressurized gas or solid fuel necessary to expand the passive restraint is disclosed. The seat structure of the aircraft comprises multiple hollow tubes, and these hollow tubes can be utilized to either store pressurized gas or solid fuel directly, or to house a vessel that stores pressurized gas or solid fuel. Thus, no additional aircraft seat space is required to house a pressurized gas vessel. By using the existing seat structure to house the source of pressurized gas or solid fuel, significant space and weight savings can be realized, both of which are important factors in aircraft seat design.