Fires in oxygen systems are most commonly attributed to flow dynamic ignition mechanisms such as particle impact and rapid pressurization heating. However, there have been fires in oxygen systems that could not be attributed to the most common ignition mechanisms. Some of these fires have been attributed to a poorly understood ignition mechanism for polymers, called “flow friction.” A brief history of fires attributed to flow friction is presented. In addition, the flow friction research that has been performed at NASA Johnson Space Center White Sands Test Facility is reviewed. Specifically, the possibility that flow friction is simple frictional heating powered by spontaneous gas-driven polymer oscillations is investigated. The results of the latest research on polymer fires based on spontaneous combustion assisted by frictional heat are presented.