Burning Plexiglass in Saffire-V orbital fire experiment

The Spacecraft Fire Safety Experiment-V (Saffire-V) successfully tested larger, more dynamic fires for over 26 hours inside Northrop Grumman’s Cygnus spacecraft, following its primary mission of delivering supplies to the International Space Station. After Cygnus departed the station on 6 January, operators on the ground, for the first time on a Saffire mission, lowered the pressure inside the spacecraft and backfilled it with oxygen to replicate potential atmospheric conditions that would likely be experienced inside future human spacecraft. After ignition, cameras and sensors monitored flame growth, temperature variations, and oxygen changes, which were translated into data. The data will be used to model fire response scenarios, as well as fire detection, combustion product monitoring, and post-fire cleanup. A sample of polymethyl methacrylate, also known as Plexiglas, was burned in the Saffire-V experiment. Ribs were manufactured into the material to see how the flame behaved when small structures were incorporated into larger materials. Researchers discovered that fires in microgravity typically grow and burn faster on the thinner ribs and materials as opposed to thicker samples on the right. See the full video here.