Merlin 1г—1 Instant

: The first to feature a regeneratively cooled nozzle and combustion chamber. It powered the first privately developed rocket to reach orbit (Falcon 1 Flight 4) and early Falcon 9 flights.

: An upgraded variant of the 1A with a more powerful turbine; it was never used on a flight vehicle before SpaceX shifted to regenerative cooling. Merlin 1Г—1

The consists of high-performance liquid rocket engines developed by SpaceX to power their Falcon 1 , Falcon 9, and Falcon Heavy rockets. Operating on a gas-generator open-cycle using RP-1 (rocket-grade kerosene) and liquid oxygen (LOX), they are renowned for their world-leading thrust-to-weight ratio and design for reusability. Key Variants and History : The first to feature a regeneratively cooled

: Drives both the LOX and RP-1 impellers. It also provides high-pressure fuel for hydraulic actuators , eliminating separate hydraulic systems. It also provides high-pressure fuel for hydraulic actuators

: Uses a triple-redundant flight computer system on each engine to ensure high reliability during launch.