Advanced Common Evolved Stage (ACES)
ULA is focused on the development of the Advanced Common Evolved Stage (ACES), supporting both Atlas V and Delta IV launch vehicle families, as a mechanism to enhance launch vehicle performance and reduce customer costs. ACES will increase the Delta IV M+(5,4) performance to cover the heavy medium class currently requiring an Atlas 551, and will increase Delta IV Heavy performance up to 37 mT.
ACES is a 5-m diameter, monocoque, common bulkhead stage that combines key features from both the Centaur and Delta Cryogenic second stages. ULA is focusing on an ACES stage containing 110 klb of propellant to satisfy a broad range of mission requirements. The ACES design is flexible enough to accommodate substantially larger or smaller propellant masses to meet future evolving mission demands. ACES will nominally use two RL10C engines. For LEO missions, ACES will accommodate four RL10C engines. Figure 8-3 shows a conceptual diagram of the ACES compared to the existing Atlas Centaur upper stage and the 5-m Delta Cryogenic Second Stage.
|Join the GlobalSecurity.org mailing list|