United Launch Alliance is preparing Vulcan for its first Amazon Leo satellite deployment after eight Atlas V missions helped build the constellation. The planned Vulcan Leo 1 mission uses six solid rocket boosters, a long payload fairing, and a new Centaur V upper stage optimized for low Earth orbit. ULA has announced November 13, 2026, as the target launch date, with 40 satellites aboard.
The mission connects two parts of the company’s current operations: completing Atlas V commitments and introducing Vulcan configurations for government and commercial customers. Vulcan already has flown national security missions. Its Amazon configuration adapts the same launch family to repeated deliveries of communications satellites into relatively low orbits, rather than the higher-energy destinations served by its initial upper-stage design.
The Company Behind Atlas and Vulcan
ULA began operations in December 2006 as a joint venture combining Boeing’s Delta and Lockheed Martin’s Atlas launch businesses. Its work includes vehicle engineering, production, mission integration, testing, and launch operations. Combining those activities brought two established rocket programs into one organization serving national security, civil government, and commercial customers.
The company identifies its headquarters functions in the Denver area and manufacturing, assembly, and integration in Decatur, Alabama. Its launch operations are based at Cape Canaveral in Florida and Vandenberg in California. These locations perform different parts of the launch service: factories produce and assemble stages, mission teams adapt the vehicle to its payload, and spaceport teams prepare and operate the flight hardware.
Mark Peller became president and chief executive officer on August 17, 2026. He previously served as chief operating officer and led Vulcan’s development. The leadership announcement identified John Elbon as his predecessor in an interim role, placing the change within the company’s transition from its older launch families to Vulcan.
ULA also announced a November 2026 agreement with Beyond Gravity to bring Vulcan fairing and composite-structure work in-house. The announced transaction covers production, sustaining engineering, and development. ULA expects the first fairing produced under the new arrangement to fly in 2027, following the planned closing of the agreement.
Vulcan’s Modular Booster
Vulcan is a two-stage launch vehicle with a liquid-fueled booster and Centaur V upper stage. Two Blue Origin BE-4 engines power the main booster using liquefied natural gas and liquid oxygen. Solid rocket motors attached around that booster supply additional thrust for missions requiring more performance. The standard family offers configurations with zero, two, four, or six solids.
This modular approach changes the vehicle’s lift capability without replacing the basic liquid booster and upper-stage architecture. A lighter mission can use fewer solids. Heavier payloads or higher-energy destinations can use more. The solid motors operate during the early ascent and separate after consuming their propellant, removing their empty mass from the vehicle that continues toward space.
Northrop Grumman supplies the GEM 63XL solid motors used by Vulcan. Their propellant is cast into the motor casing, and the internal grain geometry shapes the thrust profile as it burns. This differs from the liquid engines, which receive fuel and oxidizer from tanks through their propulsion systems. Vulcan combines both forms of propulsion during its initial climb.
ULA’s published performance table gives the six-solid configuration a 27,200-kilogram capability to its reference low Earth orbit, defined as a 200-kilometer circular orbit at 28.7 degrees inclination. The same configuration has lower capacities to more demanding destinations. Those conditions are part of the specification: a reference-orbit payload figure does not describe every possible flight path or mission configuration.
Payload Accommodation and Integration
Vulcan carries spacecraft inside a 5.4-meter-diameter fairing. ULA offers a standard fairing approximately 15.5 meters long and an extended version approximately 21.3 meters long. The fairing consists of two composite shell halves that protect the payload during ascent and separate when that protection is no longer required. The longer version provides additional room for tall spacecraft or stacked satellite deployments.
The spacecraft is enclosed inside its fairing away from the launch pad. That encapsulated assembly is then integrated with the rocket. Off-pad processing separates much of the payload-handling work from final countdown activity. The payload attach fitting provides the structural connection between the spacecraft and upper stage, carrying launch loads before releasing the spacecraft at the intended point in the mission.
ULA also offers arrangements for carrying more than one customer payload. Secondary spacecraft can occupy adapters between the primary payload and upper stage, or specialized carriers attached to the stage. The choice depends on spacecraft dimensions, mass, and deployment requirements. These arrangements use available payload volume and performance within a mission rather than requiring every spacecraft to purchase a separate rocket.
Centaur V and Orbital Delivery
Centaur V uses liquid hydrogen and liquid oxygen, with two RL10 engines supplying upper-stage propulsion. Hydrogen and oxygen are stored at cryogenic temperatures, meaning temperatures low enough to keep them liquid. After the main booster separates, Centaur performs the burns that establish the spacecraft’s destination. Its engines can restart, supporting missions with coast periods between powered maneuvers.
An upper stage’s work can extend beyond reaching an initial orbit. Some spacecraft are delivered into an elongated transfer orbit and use their own propulsion to reach the final destination. Other missions use the launch vehicle’s upper stage to perform additional maneuvers and deliver the payload more directly. The selected profile affects the stage’s propellant load, coast duration, and sequence of burns.
Vulcan’s USSF-87 mission on February 12, 2026, illustrates that second approach. ULA reported that the booster and Centaur delivered the spacecraft directly to geosynchronous orbit. The company also reported a solid-motor performance anomaly during ascent. The spacecraft delivery succeeded, and ULA announced an investigation of the motor event before the next Vulcan mission.
Geosynchronous orbit has a period matching Earth’s rotation. Direct delivery to the intended orbit can reduce the orbital-raising work required from the spacecraft. Such missions place different demands on the upper stage from a delivery to low Earth orbit, where the payload remains much closer to Earth. Vulcan’s Centaur variants are being adapted around those different mission profiles.
Centaur’s hydrogen propulsion history extends to the early U.S. lunar program. NASA’s Lewis Research Center took responsibility for the program in 1962, and Atlas-Centaur launched Surveyor 1 in 1966. Successive Centaur generations changed dimensions, engines, and mission equipment. The shared name describes that developmental family rather than an unchanged stage carried from the 1960s into Vulcan.
For ULA, the upper stage is a substantial part of the service offered to customers. The company’s position among American commercial launch providers includes direct delivery to demanding orbits as well as constellation deployment. The spacecraft, destination, and flight sequence determine which vehicle configuration is assigned to a launch.
The Low Earth Orbit Variant
The LEO-optimized Centaur V is approximately 1.8 meters shorter than the high-energy version and carries about one-third less propellant. It retains two RL10 engines and hydrogen-oxygen propulsion. ULA designed the smaller stage for Amazon missions that need less upper-stage propellant to reach their destination than higher-energy flights.
Reducing the upper stage’s structural and propellant mass allows more of the vehicle’s performance to be assigned to satellites on those missions. The change is a physical redesign of the stage, not simply a different payload arrangement. Its thin-walled stainless-steel tanks use internal pressure to support their structure, continuing the pressure-stabilized construction associated with Centaur.
ULA built a dedicated Amazon Vertical Integration Facility and a second Vulcan launch platform for this mission stream. The assembled vehicle moves from that facility to Space Launch Complex 41. A 2026 countdown rehearsal campaign exercised the new stage, platform, propellant-loading equipment, software, and launch procedures together.
The dedicated integration facility gives Amazon missions their own processing route while using the same launch pad. Vehicle assembly and pad operations are separate activities: a rocket can be prepared inside the integration building before it is moved to the pad for its countdown. This arrangement is part of the infrastructure supporting ULA’s contracted Vulcan launch series for Amazon.
Certification and Flight History
Vulcan’s first two flights were its January 2024 and October 2024 certification missions. The U.S. Space Force announced national security certification in March 2025. The process included two demonstration flights, subsystem reviews, payload-interface verifications, and hardware and software audits.
Certification established Vulcan’s eligibility for National Security Space Launch missions. USSF-106 followed in August 2025 as the first operational Vulcan launch for that program. The mission included the Navigation Technology Satellite-3 experiment, which was developed to test positioning, navigation, and timing technologies. Vulcan’s subsequent work combines those government assignments with commercial constellation deployments.
Atlas V’s Remaining Role
Atlas V uses a different main-stage propulsion system. A single RD-180 engine, with two thrust chambers, burns kerosene and liquid oxygen. Its Centaur upper stage burns liquid hydrogen and liquid oxygen. Depending on configuration, the rocket adds solid boosters and uses a payload fairing sized for the spacecraft.
The configuration number identifies the fairing class, number of solid boosters, and number of Centaur engines. Atlas V 551, for example, combines a five-meter-class fairing, five solids, and a single-engine Centaur. ULA’s reference performance table gives that configuration a low Earth orbit capacity of 18,850 kilograms under the stated orbit conditions. Other combinations serve smaller payloads or different trajectories.
Atlas V’s commercial work includes eight Amazon constellation deployment missions. On July 2, 2026, the eighth mission delivered 29 satellites. ULA reported that the eight deployment flights had carried a total of 224 Amazon satellites. The announced Vulcan series continues that deployment work using the newer launch vehicle and its dedicated infrastructure.
Atlas V also provides the launch vehicle for Boeing’s Starliner spacecraft. This version uses two solid boosters and a dual-engine Centaur. Starliner sits above the rocket through its launch vehicle adapter rather than inside the standard satellite fairing. The rocket supplies ascent propulsion, while Starliner performs spacecraft operations and carries the crew.
NASA’s Starliner launch-vehicle description explains that the dual-engine upper stage provides the thrust needed for the spacecraft’s ascent profile. Atlas V launched astronauts aboard Starliner on June 5, 2024. This configuration gives the remaining Atlas program a human-spaceflight role distinct from the satellite launch configurations that preceded it.
Retired Rockets and Continuing Upper-Stage Work
Delta IV Heavy completed its final mission on April 9, 2024, carrying NROL-70. It belongs to ULA’s retired launch history rather than its current rocket offering. Vulcan consolidates missions previously assigned across the company’s older families, while Atlas V continues the commitments associated with its remaining vehicles.
ULA also supplies upper stages for NASA’s Space Launch System. The company provided the Interim Cryogenic Propulsion Stage for Artemis I and Artemis II. An upper-stage supply contract is a different role from operating a complete launch service: NASA’s SLS is assembled from major elements supplied by several contractors, with ULA responsible for its assigned propulsion-stage work.
In October 2026, ULA announced work with NASA on a Centaur stage for Artemis. The proposed 180K-plus version has longer tanks and approximately 50 percent more propellant capacity than the current Centaur V baseline. Planned changes include alloy 718 tanks, larger hydrazine tanks, and updated avionics and software.
NASA has prioritized a qualification unit and a flight unit supporting a planned 2028 Artemis launch. ULA identifies Decatur as the manufacturing location and its RocketShip vessel as the transport route to Florida. This work extends Centaur development beyond Vulcan’s satellite-launch configurations into a separately integrated stage for NASA’s lunar launch system.
As an Amazon Associate we earn from qualifying purchases.
Useful Books Available on Amazon
