Was actually going to post a similar comment re: NASA and the SSME engines for the Space Shuttle. This graphic shows the coolant system circulation that pumps

Was actually going to post a similar comment re: NASA and the SSME engines for the Space Shuttle. This graphic shows the coolant system circulation that pumps cold fuel through the outer casing to warm it up to proper temperatures before use. [1] [1] https://en.wikipedia.org/wiki/RS-25#/media/File:Ssme_schematic_(updated).svg https://en.wikipedia.org/wiki/RS-25#/media/File:Ssme_schemat...