Mitigations
ULA’s Vulcan rocket is set to return to flight on Friday the 13th
This Vulcan launch will be the first to utilize a full complement of six solid rocket boosters.
Credit:
United Launch Alliance
Credit:
United Launch Alliance
United Launch Alliance announced Wednesday it plans to return its Vulcan rocket to service on November 13, nine months after a solid rocket booster anomaly threw the company’s 2026 launch schedule into oblivion.
The return-to-flight mission will launch 40 satellites for the Amazon Leo broadband constellation, the first of 38 Vulcan flights Amazon has booked to deploy the bulk of its network. The mission will lift off from Cape Canaveral Space Force Station, Florida, and ULA said the launch date is pending range approval.
The launch is critical for ULA after its new flagship rocket suffered nozzle failures on its solid rocket boosters on two of its first four missions, most recently during a flight in February. In both cases, the rocket overcame the nozzle failure and completed its mission, but officials at the US Space Force, ULA’s primary customer, lost confidence in Vulcan.
Space Force officials will closely scrutinize Vulcan’s return-to-flight mission. The Pentagon has entrusted ULA’s Vulcan rocket for roughly half of its major launches through the early 2030s. The Space Force certified the Vulcan rocket for national security launches in 2025, then flew two missions on Vulcan before its grounding after the February booster incident.
Making strides
In a statement, United Launch Alliance said engineers “made great strides” in understanding the booster anomaly that occurred in February. Engineers “have identified several potential contributors, which have been mitigated through design and process improvements to the nozzle,” ULA said.
“To support our customers, this upcoming launch will utilize the improved nozzle design, and additional testing and analysis will continue in parallel with the mission,” ULA said. “By flying the improved design, ULA gains valuable flight data that validates these improvements and is the most beneficial path in support of all our customers.”
ULA and Northrop Grumman, the booster manufacturer, have not publicly identified the root cause of the nozzle malfunction in February. Investigators blamed the nozzle problem’s first occurrence in 2024 on a manufacturing defect in an insulator meant to protect the nozzle’s metallic structure from the rocket’s superheated exhaust. Neither company responded to questions from Ars on Wednesday.
The Space Force is counting on United Launch Alliance, a 50-50 joint venture between Boeing and Lockheed Martin, to deliver into orbit a backlog of the military’s communications, navigation, missile warning, and surveillance satellites. Amazon Leo, a potential competitor to SpaceX’s Starlink network, also has an inventory of broadband satellites in storage waiting for rides on the Vulcan rocket.
United Launch Alliance
Credit:
United Launch Alliance
With ULA’s delays, the Space Force has moved six missions off the Vulcan rocket to expedite their launch on SpaceX Falcon 9 and Falcon Heavy rockets. ULA received six future missions originally assigned to SpaceX, the military’s other certified launch provider.
The swaps included three GPS satellites that moved off ULA’s Vulcan rocket for launches last year and earlier this year on SpaceX Falcon 9s. Space Systems Command, which oversees military launch acquisition and procurement, also swapped one ULA launch for the Space Development Agency with another on SpaceX.
A launch carrying the Air Force Research Laboratory’s Oracle-M lunar mission will now fly on SpaceX’s Falcon Heavy rocket instead of ULA’s Vulcan, which will receive a future SpaceX-assigned launch in compensation. Space Systems Command completed a similar swap to move a large strategic missile warning satellite from Vulcan to Falcon Heavy.
So far the swaps have had no effect on the number of missions the Space Force has awarded to ULA and SpaceX. The trades are separate from the Space Force’s assignment of unallocated future missions to launch providers, which may already be hamstrung by SpaceX’s plans to retire the Falcon rocket family.
“These swaps are executed in coordination with and with the support of both launch service providers,” a Space Systems Command spokesperson said. “We are grateful for the flexibility shown by our launch service providers during these swaps to help us ensure we can deliver capabilities to the warfighter when and where they are needed.”
Brig. Gen. Eric Zarybnisky, the chief rocket buyer at Space Systems Command, said the military wants to see data from commercial flights on the Vulcan rocket before clearing ULA to resume national security launches. At least two Amazon Leo missions are on the Vulcan launch schedule before it flies another national security mission, perhaps early next year.
“Those flights will have a significant number of solids,” Zarybnisky said. “It’ll depend a lot on what we see, not only on the engineering and tests that we’re doing on the ground, but also what we see from the flight data from the commercial missions they fly.”
The Vulcan launch next month will be the first to fly with a full complement of six solid rocket boosters. The flight will also debut an extended payload fairing to accommodate Amazon’s satellite stack and a shortened Centaur upper stage optimized for low-Earth orbit missions.
