Rockets

Vulcan Centaur vs. New Glenn: Two Rockets Compared

Vulcan Centaur is ULA's mostly expendable national-security rocket. New Glenn is Blue Origin's larger, reusable heavy-lifter. Both share the BE-4 engine.

New Glenn recovers and reflies its first stage. As of 2026, Vulcan Centaur does not. That is the clearest practical difference between two rockets that otherwise have more in common than most competitors, including the same first-stage engine, built by one company for two rival vehicles.

United Launch Alliance’s Vulcan Centaur and Blue Origin’s New Glenn both fly for the same national-security and commercial customers. Both rely on Blue Origin’s BE-4 engine for their first stages: Vulcan uses two, while New Glenn uses seven. Beyond that, they differ sharply in size, reusability, and overall design strategy.

The Comparison at a Glance

MeasureVulcan CentaurNew Glenn
BuilderUnited Launch AllianceBlue Origin
First-stage enginesTwo BE-4Seven BE-4
First-stage fuelLiquefied natural gas, liquid oxygenLiquefied natural gas, liquid oxygen
Upper stageCentaur, two RL10 engines, liquid hydrogen and liquid oxygenTwo BE-3U engines, liquid hydrogen and liquid oxygen
Payload fairing diameterAbout 5.4 meters7 meters
Reusability as of 2026Mostly expendable. Engine-recovery concept not yet in useFirst stage lands and reflies
Payload to low Earth orbit (expendable)Smaller than New Glenn’s advertised figureRoughly 45 metric tons (Blue Origin’s advertised figure)

One Engine, Two Different Rockets

Vulcan Centaur and New Glenn share their most important piece of hardware. Both burn the BE-4, a Blue Origin engine that runs on liquefied natural gas instead of the kerosene most rockets use. Blue Origin says that fuel choice leaves less soot on hardware meant to be reused. Vulcan carries two BE-4 engines on its first stage. New Glenn carries seven, one reason New Glenn produces far more liftoff thrust than Vulcan does. A single engine line backing two rival rockets is unusual in the launch industry. Two companies that compete for the same launch contracts are sharing one supplier, where most builders instead develop their own engines in-house.

The two rockets’ upper stages take a similar approach without sharing hardware. Vulcan’s Centaur upper stage uses two RL10 engines. New Glenn’s upper stage uses two BE-3U engines. Both pairs burn liquid hydrogen with liquid oxygen, a fuel combination that burns more efficiently than the BE-4’s natural gas. That is why both companies reserve it for the upper stage, where efficiency matters more than raw thrust.

New Glenn Reuses Its Booster. Vulcan Does Not Yet.

New Glenn’s first stage lands on a ship named Jacklyn and is meant to be refurbished and flown again, the same basic approach Falcon 9 uses. Vulcan Centaur is mostly expendable as of 2026. United Launch Alliance has described a concept for recovering just the engine section of the first stage, the two BE-4 engines, rather than catching the whole booster the way New Glenn or Falcon 9 does. That system is not flying yet.

The reuse gap traces back to each company’s priorities. United Launch Alliance built Vulcan around reliability and a fast path to national-security certification. Its predecessor rockets, the Atlas V and Delta IV Heavy, already carried decades of trusted flight history. United Launch Alliance wanted to preserve that record, rather than risk it on an unproven landing system. Blue Origin took the opposite bet with New Glenn. It chased the same cost-per-flight advantage SpaceX proved out with Falcon 9, which meant committing to full first-stage recovery from New Glenn’s first flight rather than adding it later.

United Launch Alliance is itself a joint venture between Boeing and Lockheed Martin, formed in 2006 to combine the two companies’ government rocket programs into a single launch provider. That corporate structure is part of why Vulcan’s design leans conservative. A government-focused joint venture answering to two aerospace giants has less appetite for a risky new landing system. A founder-led company like Blue Origin can commit its own capital to a longer, harder engineering bet instead.

New Glenn Lifts More and Carries It Wider

New Glenn’s advertised payload to low Earth orbit, roughly 45 metric tons in expendable mode, is larger than Vulcan Centaur’s. Its 7-meter payload fairing also beats Vulcan’s roughly 5.4-meter fairing. A large single-piece satellite or a space station module fits inside New Glenn without the folding a narrower fairing sometimes forces on a payload’s design. Vulcan’s smaller fairing still covers the great majority of satellites flying today. Solid rocket boosters can be added to Vulcan for heavier missions that need the extra push. New Glenn’s own design does not offer that same modular option.

Both Rockets Carry National-Security Missions

The US Space Force certifies more than one heavy-lift rocket on purpose. A single vehicle’s grounding then never stops every classified or missile-warning satellite from reaching orbit. Vulcan Centaur is certified for national-security launches today and also carries commercial payloads, including satellites for Amazon’s Project Kuiper broadband constellation. New Glenn carries a similar mix: national-security and commercial satellites, some of Kuiper’s own constellation among them, plus Blue Origin’s Blue Moon lunar landers and NASA planetary science payloads. Amazon in particular books launches across both rockets rather than depending on either provider alone. That spreads Kuiper’s deployment schedule across whichever vehicle has an open launch slot.

What Would Change This Comparison

A working engine-recovery system for Vulcan Centaur would narrow the reuse gap that currently favors New Glenn. A confirmed, mission-specific payload figure from either provider would sharpen today’s advertised-capacity comparison too. Readers who want the full mechanics behind each rocket can start with the Vulcan Centaur explainer and the New Glenn explainer. The reusable rockets guide covers why recovering a booster’s engines alone is a different, easier engineering problem than recovering the whole stage.

Frequently asked questions

Do Vulcan Centaur and New Glenn use the same engine?

Yes, both burn Blue Origin's BE-4 engine on their first stage, one of the few cases where a direct rocket rival supplies hardware to a competitor. Vulcan uses two BE-4 engines. New Glenn uses seven. Blue Origin builds the same engine line for both vehicles, even though United Launch Alliance and Blue Origin compete for many of the same national-security launch contracts.

Is Vulcan Centaur or New Glenn reusable?

New Glenn's first stage is designed to land and refly, the same approach Falcon 9 uses. Vulcan Centaur is mostly expendable as of 2026. United Launch Alliance has described a concept for recovering just the first stage's engines rather than the whole booster. That engine-recovery system is not in use yet.

Which rocket can carry more, Vulcan Centaur or New Glenn?

New Glenn. Its advertised payload to low Earth orbit, roughly 45 metric tons in expendable mode, is larger than Vulcan Centaur's. Its 7-meter payload fairing is also wider than Vulcan's roughly 5.4-meter fairing, so it fits bigger single-piece payloads without folding them.

Why does the US Space Force use both Vulcan Centaur and New Glenn?

National-security satellites are too valuable to risk on a single rocket. The US Space Force certifies more than one heavy-lift provider on purpose. A problem grounding Vulcan then does not stop every classified or missile-warning launch, and the same protection runs the other way if New Glenn is the one grounded.

What does Vulcan Centaur replace?

Vulcan Centaur replaces two older United Launch Alliance rockets, the Atlas V and the Delta IV Heavy, folding both roles into one vehicle. Part of the reason was to move away from the Atlas V's Russian-made RD-180 engine and standardize on the Blue Origin-built BE-4 instead.