Study of the NewTrust nuclear propulsion engine for manned Mars missions

The performance of NTP engines consistent with the two HALEU core options described in the literature is assessed. The engine cycle and performance were evaluated using hydrogen as the propellant. The specific impulse is 896 s, with a thrust ranging from 66 kN (UN cermet core) to 113 kN (NERVA-like core). Next, calculations for a manned Mars mission are presented. Various operational concepts are investigated by varying the number of engines, their thrust, the reactor cooldown propellant flow rate, and the number of tanks. Gravity losses are quantified for each mission maneuver. A conjunction-class mission with four engines and four tanks (ΔV of 11.8 km/s) requires a vehicle mass of 450 tons carrying 320 tons of hydrogen. An opposition class mission with six engines and six tanks (ΔV of 15.5 km/s) multiplies the hydrogen mass by a factor of two (with an initial vehicle mass exceeding 800 tons) compared to a conjunction class mission. For reference, the International Space Station weighs approximately 420 tons. This study confirms NTP interest since the propellant mass needed for combustion engines is about five times larger for conjunction class missions and eight times larger for opposition class missions compared to NTP engines.