Scott Manley in the X thread said "So, is the turbine section driving a generator to make electricity to power the compressor" and Ian Brooke replied "Exactly t

Scott Manley in the X thread said "So, is the turbine section driving a generator to make electricity to power the compressor" and Ian Brooke replied "Exactly that. ... The key insight is to use electric motors to drive a compressor. That way we can make it spin at any speed, allowing it to "adapt" to it's airspeed and combustion cycle."