Preliminary Results from the Saffire VI Experiment

David L. Urban; Gary A. Ruff; Paul Ferkul; John Easton; Jay Owens; Sandra Olson; Claire Fortenberry; John Graf; Oageng George; Balazs Toth; Florian Meyer; Christian Eigenbrod; James S. Tien; Ya-Ting T. Liao; A. Carlos Fernandez-Pello; Guillaume Legros; Augustin Guibaud; Nickolay Smirnov; Osamu Fujita; Ulises Rojas Alva; Grunde Jomaas

NASA NTRS · 20240007488

Preliminary Results from the Saffire VI Experiment

Abstract

The preliminary results are presented for one test of the last flight of the Spacecraft Fire Experiment (Saffire VI) which was conducted on an orbiting Cygnus spacecraft. These experiments directly address the risks associated with our understanding of spacecraft fire behavior at practical length scales and geometries. The lack of this experimental data has forced spacecraft designers to base their designs and safety precautions on 1-g understanding of flame spread, flame self-extinguishment, fire detection, and suppression. The Saffire experiment was developed by an international team of investigators with the goal of addressing open issues in spacecraft fire safety. NASA’s Spacecraft Fire Safety Demonstration Project was designed with the goal of conducting a series of large-scale experiments in spacecraft environments that represent practical spacecraft fires. The final flight examined concurrent spread over large samples (all 41 cm wide) including a thin sheet of flammable fuel (cotton/fiberglass 50 cm long); 2-sided spread over 1 cm thick polymethyl methacrylate (PMMA) (18 cm long) ; 1-sided spread over 0.5 cm thick (18 cm long); and Nomex fabric (7 cm long). This paper focusses on the two-sided PMMA sample. The flame heat release is determined and is compared to the overall temperature rise in the spacecraft and the change in the concentration of carbon dioxide and carbon monoxide in the spacecraft.

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David L. Urban, Gary A. Ruff, Paul Ferkul, John Easton, Jay Owens, Sandra Olson, Claire Fortenberry, John Graf, Oageng George, Balazs Toth, Florian Meyer, Christian Eigenbrod, James S. Tien, Ya-Ting T. Liao, A. Carlos Fernandez-Pello, Guillaume Legros, Augustin Guibaud, Nickolay Smirnov, Osamu Fujita, Ulises Rojas Alva, Grunde Jomaas. Preliminary Results from the Saffire VI Experiment. https://ntrs.nasa.gov/citations/20240007488

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