Reducing the risk of fire in spacecraft and human habitats
The Solid Fuel Ignition and Extinction (SoFIE) Mission operates as a facility aboard the International Space Station and will support multiple experiments to study the flammability of materials commonly used in spaceflight and help predict how those materials will burn in lunar or Martian gravity.
Results from SoFIE experiments will contribute to safer selection of materials and improved design of spacesuits, cabins, and habitats. It also will help NASA identify the best ways to put out fires or smoldering materials in space.
SoFIE also could lead to improved fire safety on Earth, such as better screening tests to evaluate how fire safe a material is for the home, office, aircraft, or other uses.
Why is SoFIE Important?
On Earth, gravity has a large influence on flames. At reduced gravity, such as on the International Space Station (microgravity) or on the Moon (lunar gravity), fire acts differently and can behave unexpectedly. There is some evidence that fires can be more hazardous in reduced gravity, which is a concern for fire safety. Understanding flame spread and behavior of solid materials in different environments in space is crucial for the safety of future astronauts and for understanding and controlling fire here on Earth.
- improve understanding of how fires are ignited and grow in reduced gravity
- improve extravehicular activity suit design
- inform safer selection of cabin materials
- validate NASA’s approach to testing spaceflight materials for flammability in low gravity
- validate the numerical models NASA uses to predict the flammability of materials in space
- determine the best techniques for suppressing fires in space
The primary purpose of the SoFIE is to improve fire safety for future long-term missions to the Moon and eventually Mars or other planets. However, data collected by the facility could provide better understanding of fire safety and improved materials screening tests for evaluating how fire safe a material is for homes, offices, aircraft, and other uses.
Thus far, five investigations have been selected as part of the SoFIE facility. Each investigation addresses different elements of material flammability (flame spread, flame growth, decay and extinction, flow, and gravity flammability) and helps further our understanding of solid surface combustion and material flammability.
- Growth and Extinction Limit of Solid Fuels (GEL) - This experiment will concentrate on the flame growth, decay, and extinction over the surface of a non-flat thick solid in microgravity.
- Material Ignition and Suppression Test (MIST) - The MIST experimental apparatus consists of a small-scale combustion wind tunnel, a cylindrical fuel sample, radiant heaters, an igniter, and supporting instrumentation.
- Residence Time Driven Flame Spread (RTDFS) - The RTDFS experiment investigates steady and unsteady flame propagation over solid fuels in a microgravity environment.
- Spacecraft Materials Microgravity Research on Flammability (SMuRF) - The SmuRF experiment correlates normal gravity flammability test data with data under ventilated microgravity conditions.
- Narrow Channel Apparatus (NCA) - The experimental approach is to measure flame spread across planar samples of PMMA in a forced opposed flow configuration.