ULA Nuclear ACES for Outer Planet missions

Hypothesis

Attempt to use common avionics and communications with chemical propellent LO2/LO2 ACES. Keep the ICE and GH2/GO2 thrusters to generate electricity and to utilize boil off the cryogenic propellants for the ICE engine

This is a proposed deep space long-lived ACES stage so an LO2 propellant tank is nestled inside the much larger LH2 tank

This stage would utilize a small nuclear thermal engine and the LH2 propellant tank would house inside it a smaller LO2 tank for running the ICE and station keeping maneuver engines

There would not be an LH2/LO2 engine so the LO2 tank could be small enough for the ICE engine.LH2 would keep the LO2 cool.At some point, ULA NTR ACES could pick up its LO2 for planetary missions from a lunar source

LunarLOX/NTR

LunarLOX/NTR 2

Weight of ACES stage

reduce LO2 tank mass

Increase LH2 tank size

subtrate weight of a chemical engine

Add the weight of the fission engine

PeeWee small fission rocket  3,300 Kg

SNRE small fission rocket    2,400 Kg

worksheet

ULA ACES dry mass 4.6 Mt

SNRE engine                2.4 Mt

science payload            1 Mt

ESPA rings plus RTG

plus electrical cabling

communications   1 Mt

Totals 9 Mt