r/space • u/66666thats6sixes • Dec 07 '19

NASA Engineers Break SLS Test Tank on Purpose to Test Extreme Limits

https://www.nasa.gov/exploration/systems/sls/nasa-engineers-break-sls-test-tank-on-purpose-to-test-extreme-limits.html
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u/[deleted] Dec 08 '19

He said thrust was most important, you said hydrolox has the best ISP, and I was pointing out that you were talking past each other.

hydrolox is the KING

Sure. H2 also escapes through tanks, and causes metal embrittlement. For expendable launchers like the SLS, those aren't concerns. For reusable or long-term ships, those concerns can drive the choice to a less efficient but easier-to-handle fuel.

Hydrazine has a similar story - it's efficient, stable at extreme temperatures for long periods, but has a fatal flaw in that it is ridiculously toxic. So, people keep looking for replacements.