A United Launch Alliance (ULA) Vulcan rocket launched successfully on March 14, 2024, but encountered a potential issue during its ascent. The rocket, carrying a suite of classified Space Force payloads, experienced what appeared to be a burn-through at the nozzle of one of its strap-on solid-fuel boosters shortly after liftoff. Despite this, ULA reported that the rocket’s ascent remained “nominal.”
The Vulcan rocket ignited at 09:22 UTC from pad 41 at the Cape Canaveral Space Force Station, generating an impressive 2.9 million pounds of thrust from its twin methane-burning Blue Origin BE-4 engines and four Northrop Grumman solid-fuel boosters. The initial phase of the flight went smoothly; however, approximately 20 seconds after launch, one of the GEM 63XL boosters experienced a nozzle burn-through, resulting in a visible jet of flame.
“We had an observation early during flight on one of the four solid rocket motors,” ULA stated in a post on social media platform X. “The team is currently reviewing the data.” Despite the anomaly with the booster, the Vulcan’s core stage, upper stage, and spacecraft continued to function as expected.
As the rocket progressed, tracking cameras captured it beginning to roll rapidly along its long axis shortly before the boosters were jettisoned. The cause of this unexpected motion remains unclear; it could be linked to the thrust from the damaged nozzle or another issue entirely. Notably, the unusual movement ceased after the boosters were discarded.
Following standard protocol for classified military missions, ULA concluded its launch broadcast shortly after the ignition of the second stage engine. Updates on the mission are not anticipated until its completion, which is expected to last around 10 hours.
This launch marked the fourth overall flight for ULA’s Vulcan, a heavy-lift rocket designed to replace the Atlas 5 and Delta 4 launch vehicles. The Vulcan’s prior missions included two certification flights in 2024 to validate the rocket’s capability for high-value national security payloads. A nozzle failure during the second certification flight had previously prompted a detailed investigation and subsequent corrective measures. The third flight in 2025 successfully deployed the rocket’s first Space Force payload.
Before the launch, ULA officials announced plans for over 20 flights in 2024, including two to four Atlas 5 missions and 16 to 18 Vulcan launches utilizing facilities on both coasts. The impact of the recent nozzle failure on this schedule remains uncertain.
The primary payload for Thursday’s mission was a Geosynchronous Space Situational Awareness Program (GSSAP) satellite constructed by Northrop Grumman. This satellite is intended to monitor the behavior and movement of other satellites in geosynchronous orbit, which is approximately 22,300 miles above the equator. At this altitude, satellites maintain a fixed position relative to the Earth, making it a preferred orbit for various civilian and military applications.
According to Gary Wentz, ULA Vice President of Atlas and Vulcan Programs, the GSSAP satellites enhance the United States’ ability to detect and evaluate disturbances in space systems. Prior to this launch, ULA successfully deployed six GSSAP surveillance stations in pairs during missions in 2014, 2016, and 2022.
In addition to the GSSAP satellite, the Vulcan’s nose cone housed an ESPAStar spacecraft, a solar-powered platform capable of supporting a mix of hosted and separable payloads. All payloads launched during this mission were classified.
This mission is significant as it represents the longest flight yet for a ULA rocket, lasting approximately 10 hours and targeting multiple points in near-geosynchronous orbit. “This is the type of mission that the team actually designed this launch vehicle to support,” Wentz commented. “It’s significant payloads to very complex orbits, multi-manifested national security space, direct-to-geo. So this is tailor-fit for that mission.”
The United Launch Alliance is a joint venture between Boeing and Lockheed Martin, with both companies holding equal stakes in the enterprise.
