Luke Leisher
@luke_leisher_ · Nov 2, 2025
Just realized that as far as the public information reveals, raptor now matches Merlin on TWR and beats it out on Price/Ton of trust.
Greatest engineering in the world.
Elon Musk@elonmusk· Feb 21, 2019@fan_of_racing @bkent136 @macodiseas @katlinegrey SpaceX Merlin architecture is simpler than staged combustion (eg SSME or RD), but it has world record for thrust/weight & thrust/cost engine. Raptor has better Isp, but I’m worried it may fall short on those two critical metrics.
Elon Musk
@elonmusk
Raptor 3 will probably be 2 to 4 times better than Merlin in $/ton of thrust and will exceed Merlin in thrust to weight ratio.
Raptor 4 should beat Merlin by >10X in $/ton of thrust, with further improvement in TWR and ISP.
03:30 AM · November 3, 2025 · 565.1K views
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