spending less fuel, the other, correspondingly with less efficiency, spending more fuel, our friends from kbhad the assigned... task. the developers of rd-0124 managed to squeeze out of it the maximum efficiency that is generally possible for oxygen-kerosene engines. thrust in vacuum is 30 tons of force, specific thrust impulse is 3.522 m/s. experts say that the world's best rocket engine manufacturers, even spacex specialists, will envy such figures. by the way, in their falcon 9 rocket they use a head fairing made of composite materials; it is about 20% lighter than the standard aluminum one. composites are the main trend of modern rocketry technology, that is, they have reached parameters and characteristics of these composites that they could not even dream of before, but have now developed. composites with characteristics that allow composites to compete with, well , steel, the bottom line is the payload, the payload will be greater, yes, if you use a composite. only two missiles in the world, the american falcon and the russian hangar, now have lightweight head fairings made of composite