The DCSS employs a unique two-tank architecture where the cylindrical liquid hydrogen (LH2) tank carries payload launch loads and forms the upper section.

The DCSS is powered by a single RL10B-2 engine built by Aerojet Rocketdyne,[2] which features an extendable carbon–carbon nozzle to improve specific impulse.

On the third flight, the DCSS performed its planned burn but fell short of the target orbit due to premature propellant exhaustion, resulting in mission failure.

Like the earlier DCSS, the ICPS is powered by one Aerojet Rocketdyne RL10 engine and generates 110.1 kilonewtons (24,800 pounds-force) of maximum thrust.

[10] The ICPS is designed as a temporary solution and slated to be replaced by the next-generation Exploration Upper Stage for the Artemis IV mission and beyond.