Vulcan Centaur VC2S / Vulcan Centaur VC2L

Vulcan-Centaur VC2S (Peregrine) [ULA]

The Vulcan launch system, provisionally called NGLS (NGLS), is a replacement under development by ULA (United Launch Alliance) to replace both the Atlas-5 and Delta-4 families.

The vehicle familiy is built on the base vehicle core featuring 5 m diameter tankage inherited from the Delta-4 and a LOX / LNG fueled propulsion system using two Blue Origin built BE-4 engines. The basic stage can be enhanced by two, four or six GEM-63XL solid motors manufactured by Northrop Grumman Innovation Systems (NGIS) (formerly Orbital ATK).

Initally Stage 1 will be expendable. Later the Sensible, Modular, Autonomous Return Technology (SMART) initiative might be introduced, which allows ULA to reuse the most expensive portion of the first stage – the booster main engines – via mid-air capture. This allows a controlled recovery environment providing the confidence needed to re-fly the hardware.

Initially the 3.05 m diameter Centaur-3 upper stage of Atlas-5 was to be used with 4 m and 5 m fairings. In early 2018, it was decided to skip these versions.

The initial Vulcan versions will now feature a 5.4 meters diameter Centaur-5 stage, featuring two RL10C-1 engines. After Centaur-5 an improved variant, Centaur-5+, will be introduced with an engine upgrade in a 2 engine configuration. A Centaur-5+Long will be implemented later, which will support 170klb of propellants and is not yet decided if it is to use two or four engines.

Finally, the Centaur second stage was originally be replaced by the more powerful ACES in 2023, which shares the tooling with Centaur-5. With the addition of ACES, Vulcan will achieve the current capability of the Delta-4 Heavy, which carries the largest payloads for the most critical customers. ACES will feature initially one to four RL10 engines, later to be downselected to BE-3U or XCOR engines. Later ACES was shelved and many features were incorporated in Centaur-5.

Vulcan Centaur-5 and Vulcan ACES will use 5 m payload fairings.

The Atlas-5 launch pads, SLC-41 at Cape Canaveral AFB and SLC-3E at Vandenberg AFB, will be modified to launch the Vulcan-boosters.

The maiden launch was planned for 2021, but had been delayed to January 2024.