The F-1B engine has a design goal to be at least as powerful as the unflown F-1A, while also being more cost effective. The design incorporates a greatly simplified combustion chamber, a reduced number of engine parts, and the removal of the F-1 exhaust recycling system, including the turbine exhaust mid-nozzle and the "curtain" cooling manifold, with the turbine exhaust having a separate outlet passage beside the shortened main nozzle on the F-1B. The reduction in parts costs is aided by using selective laser melting in the production of some metallic parts. The resulting F-1B engine is intended to produce of thrust at sea level, a 15% increase over the approximate of thrust that the mature Apollo 15 F-1 engines produced.