John Bucknell created the pre-conceptual design for the SpaceX Raptor engine. It will be the advanced full-flow staged combustion rocket engine for the SpaceX BFR. He designed and built the subscale Raptor rocket for proof of concept testing able to test eighty-one configurations of main injector.
John Bucknell says the nuclear turbo rocket technology and his designs are ready for development. The air-breathing nuclear thermal rocket will enable 7 times more payload fraction to be delivered to low-earth orbit and it will have 6 times the ISP (rocket fuel efficiency) as chemical rockets. The rocket will have two to three times the speed and performance of chemical rockets for missions outside of the atmosphere.
The fully reusable nuclear rocket will be a single stage to orbit system which will be able to make space-based solar power several times cheaper than coal power. Using the 11-meter diameter version of this rocket to build space-based solar power will enable solar power at less than 2 cents per kilowatt-hour.
Besides being cheaper and vastly higher performing that the SpaceX BFR, the Bucknell Nuclear turbo rocket will to do things which the SpaceX BFR cannot.
Bucknell’s proposed air-breathing nuclear thermal rocket propulsion cycle called the Nuclear Thermal Turbo Rocket (NTTR) improves payload fraction to Low Earth Orbit (LEO) by a factor of 5-7 relative to State of the Art chemical rockets.
Mission Average Specific Impulse: 1430 to 1788 sec (About 5-6 times better than 350-400 ISP chemical rockets)
The Nuclear Thermal Turbo Rocket (NTTR) is a supercharged air-augmented nuclear thermal combined cycle rocket architecture.
Nuclear turbo rockets already offer the highest Specific Impulse (Isp) of launch-capable pure rocket propulsion systems, whereas launch to hypersonic turbine combined cycle systems offer far higher Isp. The NTTR combines both modes.
The Turbo Rocket architecture represents a new paradigm for access to space economics.
Large payload fractions of 35-50%, Low Construction Cost and Full Reuse
Cost to LEO: less than $85/kg w/10 flights
Cost to Luna: less than $715/kg w/10 flights
Staged Combustion: Lowest Cost to LEO
Nuclear Thermal: Lowest Cost for Near Earth Return and Larger Payloads to Everywhere
The Turbo Rocket architecture is the first such known to be able to achieve payload fractions to LEO above 44%, representing an order of magnitude improvement over the state of the art.