The Rocket Engine is a critical component in any functioning rocket. This all-in-one engine/nozzle combo is perfect for igniting and then directing the hot gasses produced by combustion in a downwardly direction.
When used in a rocket, the engine can produce thrust, which is required to move the rocket upward, or at least a little less downward.
There are two types of engines each with a basic and advanced engine. Monopropellant uses 2 mB/t of rocket fuel. Bipropellant uses 1mB/t each of hydrogen and oxygen and requires 1 of each tank on the rocket. The advanced engines require 3x as much fuel but provides 5x the thrust.