SpaceX Raptor Engine Will Be Best on Cost and Nearly Best on ISP

Tim Dodd, Everyday Astronaut, has a detailed analysis of the SpaceX Raptor engine compared to the F-1 Saturn Five, Space Shuttle RS-25, the Russian RD-180 – used on US Atlas rockets and the Blue Origin BE-4.

SpaceX Merlin engine costs less than $1 million. Elon has said SpaceX produce the Raptor for cheaper than or close to the Merlin engine in later simplified Raptor versions. Tim estimates current Raptors at $2 million.

The Raptor will have a vacuum version with an ISP of 350 and a sea level version with an ISP of 330. ISP is rocket engine fuel efficiency.

The Raptor will have higher ISP than any rocket other than the Space Shuttle, but the Raptor will be 70 times cheaper than the Space Shuttle engine on a cost for constant power level basis.

SOURCES- Everyday Astronaut