United Launch Alliance’s Vulcan Centaur rocket lost 40 Amazon Leo internet satellites after an in-flight anomaly 10 minutes into its Sunday launch from Florida.
The heavy-lift vehicle thundered away from Space Launch Complex 41 at the Cape Canaveral Space Force Station at 12:40 p.m. ET. It generated nearly 3.8 million pounds of thrust from two methane-powered BE-4 main engines and six Northrop Grumman strap-on solid-fuel boosters. But during the Centaur upper stage burn, the mission failed to reach orbit.
“Based on data received by our Launch Director, we confirm that the Vulcan vehicle launched from Space Launch Complex 41 suffered an anomaly 10 minutes into the flight and failed to deliver the Amazon mission to orbit,” United Launch Alliance said in an update on X.
Multiple sources say the anomaly that impacted today's Vulcan launch occurred in the booster stage, not the Centaur V upper stage or SRBs. I don't yet know if the booster stage issue was caused by the BE-4 engines, the propellant management system, or another problem.
“We will work closely with our customer and other appropriate organizations to find the cause, determine the appropriate corrective action and return to flight as quickly as possible,” United Launch Alliance said.
Sunday’s flight was the first of 38 planned Vulcan launches bought by Amazon to build out its low-Earth-orbit broadband constellation, designed to rival SpaceX’s Starlink service. The spacecraft manufacturer had already launched eight Leo missions using older Atlas V rockets. Amazon also booked flights on Blue Origin’s New Glenn, Arianespace’s Ariane 6, and SpaceX’s Falcon 9.
Based on data received by our Launch Director, we confirm that the Vulcan vehicle launched from Space Launch Complex 41 suffered an anomaly 10 minutes into the flight and failed to deliver the Amazon mission to orbit. Every flight generates data, and every flight teaches us…
The mission followed multiple delays. These included a power interruption at an Air Liquide gaseous nitrogen plant that cut deliveries to the launch pad, followed by a network communication issue between ground equipment and the rocket.
The flight was the first for Vulcan in nine months. A grounding had been prompted by solid rocket booster nozzle issues during national security missions in February and October 2024. ULA said that the solid boosters appeared to perform normally on Sunday, separating as planned before the failure struck during the upper stage burn.
“Every flight generates data, and every flight teaches us something. Since the anomaly just occurred, we don’t have any specific data yet to understand what occurred today,” the company said in an emailed statement.
NASA Administrator Jared Isaacman offered assistance via social media following the mishap.
“Appreciate you quickly keeping the public and your partners informed. The team at @NASA is available to assist in all matters related to the investigation and remediation effort. Artemis, Moon Base, and the nation need ULA. We are in your corner and here to help,” Isaacman said on X.
The event hit United Launch Alliance, a joint venture formed by Boeing and Lockheed Martin in 2006. According to reporting from Spaceflight Now, this incident represents the first outright failure of a United Launch Alliance rocket since the joint venture started nearly two decades ago.
There is risk with any launch, and that’s especially true for inaugural missions like LV-01. ULA has been a trusted partner for Amazon, and we believe they’ll learn from this mission and deliver on their long-term plans for Vulcan. Full statement from @ulalaunch below. https://t.co/lS2GEioSak
Amazon Leo, formerly known as Project Kuiper, relies on successful flights to scale its broadband network. The initiative requires launching thousands of satellites into low-Earth orbit to provide high-speed global connectivity. Before Sunday’s attempt, Amazon placed roughly 400 spacecraft into orbit across 14 separate missions deployed by Atlas V, Falcon 9, and Ariane 6 rockets since April 2025.
Melissa Wuerl, the director of launch systems for Amazon Leo, said that the Vulcan vehicle was intended to serve as the program’s primary workhorse over the coming years. It was set to handle more than 1,500 spacecraft from the first-generation deployment.
And LIFTOFF of the first Vulcan Amazon Leo mission, carrying 40 broadband satellites to low Earth orbit! pic.twitter.com/dv1MSjJUMF
Don Platt, director of the Spaceport Education Center at Florida Tech, said that a healthy market requires multiple launch providers to ensure reliable access to space, making alternatives important for commercial partners and future missions.
Earlier coverage: Vulcan Rocket Fails on Amazon LEO Mission
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