John Honeycutt, chair of NASA’s Artemis II mission management team, said the decision to relax the safety limit between Artemis I and Artemis II was grounded in test data.
“The SLS program, they came up with a test campaign that actually looked at that cavity, the characteristics of the cavity, the purge in the cavity … and they introduced hydrogen to see when you could actually get it to ignite, and at 16 percent, you could not,” said Honeycutt, who served as NASA’s SLS program manager before moving to his new job.
Hydrogen is explosive in high concentrations when mixed with air. This is what makes hydrogen a formidable
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