Is the Falcon 9 second stage Merlin vacuum engine throttled down during its burn to limit the maximum acceleration experienced by the Dragon or Crew Dragon capsule?

As the second stage consumes propellant the mass decreases and with constant thrust the acceleration will continue to increase. The first stage reduces power in order to limit forces during the approach to max Q, is this also necessary for the second stage to throttle back to limit max g?


1 Answer 1


An enthusiast analysed the telemetry shown in SpaceX launches, which appears to show a significant throttle down for the Orbcomm2 mission. analysis

The question What makes the Merlin vacuum engine so deeply throttleable? discusses the throttling capability.

However the capability doesn't appear to be used in most missions (including the crew carrying demo-1)


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