Valcor Engineering Corporation proposes to develop an advanced On Board Inert Gas Generation System, OBIGGS, for aircraft fuel tank inerting to prevent hazardous in-flight conditions and to mitigate their effect when they do occur. Aircraft fires represent a small number of actual accident causes, but the number of fatalities due to in-flight, post-crash, and on-ground fires is large. The novel OBIGGS system will inert aircraft fuel tanks with nitrogen generated by a hollow fiber membrane module. The system will provide a cost effective method for fuel tank inerting, will be robust and resistant to chemical contamination. An OBIGGS system that is based on nitrogen generation is environmentally friendly and does not require hazardous chemicals for fire suppression. In addition to improving aircraft safety by mitigating hazardous in-flight and on the ground conditions the OBIGGS systems will also contribute to aircraft security and will mitigate aircraft damage from hostile attacks.