Vulcan Centaur
United Launch Alliance
United Launch Alliance's next-generation heavy-lift rocket, replacing the Atlas V and Delta IV, powered by Blue Origin BE-4 engines and a Centaur V upper stage.
Technical specifications
- Height
- 61.6 m (standard fairing); 67.3 m (long fairing)
- Diameter
- 5.4 m
- Stages
- 2 (first stage/booster + Centaur V upper stage)
- First stage engines
- 2x Blue Origin BE-4 (LNG/LOX)
- First stage thrust
- 550,000 lbf per engine (sea level); ~4,893 kN combined
- Upper stage engines
- 2x RL10C (LH2/LOX), restartable
- Solid rocket boosters
- 0, 2, 4, or 6x Northrop Grumman GEM 63XL
- Payload to LEO (6 boosters, VC6S)
- 27,200 kg
- Payload to GTO (6 boosters, VC6S)
- 14,400-15,300 kg
- Payload to GTO (0 boosters, VC0S)
- 3,300-3,500 kg
- Flight heritage
- Cert-1: Jan 8, 2024, success. Cert-2: Oct 4, 2024, success despite SRB nozzle separation ~37s into flight. USSF-106: Aug 13, 2025, first operational NSSL mission, success. USSF-87: Feb 12, 2026, second SRB anomaly reported, prompting a temporary USSF pause on further NSSL Vulcan launches pending review. 25+ missions manifested for 2026 including Kuiper and Dream Chaser resupply flights.
About
Vulcan Centaur is United Launch Alliance’s current two-stage heavy-lift launch vehicle, developed to succeed the Atlas V and Delta IV families. The first stage is powered by two Blue Origin BE-4 engines burning liquefied natural gas and liquid oxygen, producing roughly 4,893 kN of combined thrust at sea level. The vehicle can be augmented with 0, 2, 4, or 6 Northrop Grumman GEM 63XL solid rocket boosters to tailor performance to mission needs. The upper stage is the Centaur V, featuring two RL10C engines with restart capability. Vulcan Centaur serves U.S. national security space launch missions, NASA and commercial payloads, and Amazon’s Project Kuiper broadband satellite constellation. It completed its Cert-1 certification flight on January 8, 2024 (carrying the Astrobotic Peregrine lunar lander) and Cert-2 on October 4, 2024 (which reached nominal orbit despite an SRB nozzle anomaly). Following certification, Vulcan began flying operational NSSL missions, including USSF-106 in August 2025, with additional national security, commercial, and Kuiper missions conducted into 2026, though a further SRB-related anomaly on USSF-87 in February 2026 prompted a temporary Space Force pause on NSSL launches pending investigation.
Documentation
No public datasheet yet — request the datasheet / ICD from the supplier.