I'm trying to understand how much different parts of a rocket engine weigh. For example, according to Wikipedia, Merlin engine weighs 470 kg, of which 70 kg is the turbopump. How is the remaining 400 kg break out? I'm guessing the broad categories could be:

  1. Turbopump(s)
  2. Combustion chamber
  3. Nozzle
  4. Plumbing
  5. Thrust frame
  6. Swing assembly

Totally understand that this breakdown might vary greatly for different engines, but if someone knows directional numbers for different types of engines (turbopump vs. staged combustion vs. expander cycle, maybe on an example of real engines - e.g. Merlin, RL10 etc.), would appreciate the info!

  • $\begingroup$ Two more components: thrust frame (keeps the parts together and transfers load to the rocket) and swing assembly (hydraulic tilt mechanism for thrust vectoring). The RD-191 and RD-193 are interesting in that regard, as they differ only in the presence/absence of thrust vectoring. $\endgroup$
    – Rainer P.
    Commented Jan 30, 2020 at 23:49
  • $\begingroup$ @RainerP. - thanks! Updated. $\endgroup$
    – irakliy
    Commented Jan 31, 2020 at 1:01
  • $\begingroup$ btw, very interesting info on RD-191/193 - seems like the swing assembly weight was over 300kg or about 15% of the mass. $\endgroup$
    – irakliy
    Commented Jan 31, 2020 at 1:09
  • $\begingroup$ @RainerP. surprised the swing assy is considered part of the engine. $\endgroup$
    – ikrase
    Commented Jan 31, 2020 at 5:51
  • $\begingroup$ This link is full of fantastic design info, although no weight data: everydayastronaut.com/raptor-engine $\endgroup$ Commented Jan 31, 2020 at 13:28

1 Answer 1


Here is a partial answer to your question: The Saturn F1 engine weighed 18,000 pounds The Space Shuttle SSME weighs ABOUT 7,000 pounds See https://gandalfddi.z19.web.core.windows.net/Shuttle/SSME_MPS_Info/RSS-8559-1-1-1-19990041880.pdf This is a chart of the weight of the turbopumps, out of the powerhead, pumps, plumbing and nozzle I think the nozzle would weigh the most as a single component (depends on how you break it down): enter image description here


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