A United Launch Alliance (ULA) Vulcan rocket successfully launched on March 15, 2024, carrying classified payloads for the Space Force, despite experiencing a nozzle issue with one of its solid-fuel boosters. The rocket lifted off from Cape Canaveral Space Force Station at 09:22 UTC, generating an impressive 2.9 million pounds of thrust from its dual methane-fueled Blue Origin BE-4 engines and four Northrop Grumman GEM 63XL boosters.
The initial phase of the ascent appeared to proceed smoothly; however, approximately 20 seconds after liftoff, one of the strap-on boosters showed signs of distress. ULA reported what seemed to be a burn-through at or near the nozzle, resulting in a visible jet of flame emanating from the booster. The company stated in a post on X, “We had an observation early during flight on one of the four solid rocket motors. The team is currently reviewing the data.” Despite this complication, the Vulcan’s core stage, upper stage, and spacecraft continued to perform normally.
Shortly before the boosters were detached, tracking cameras indicated an unusual rolling motion of the rocket around its long axis. While it remains unclear if this was directly linked to the nozzle failure, the motion stabilized after the boosters were released. As is customary with classified military missions, ULA ceased its launch broadcast shortly after the ignition of the second-stage engine, with no further updates expected until the completion of the 10-hour mission.
This launch marked the fourth overall flight of ULA’s Vulcan rocket, which is designed to replace the Atlas 5 and Delta 4 launch systems. The Vulcan is significant for its all-American components, moving away from reliance on Russian-built engines. ULA has conducted two certification flights in 2024, aimed at qualifying the Vulcan for national security payloads. The previous certification flight faced a nozzle failure, prompting a comprehensive investigation and subsequent corrective measures. The Vulcan’s third flight in 2025 successfully deployed its first Space Force payload.
ULA officials indicated a busy launch schedule for 2024, with plans for over 20 flights, including 16 to 18 Vulcan missions and a couple of Atlas 5 launches, utilizing facilities on both U.S. coasts. It remains uncertain if the booster nozzle issue will affect this timeline.
The primary payload of Thursday’s launch was a Geosynchronous Space Situational Awareness Program (GSSAP) satellite, constructed by Northrop Grumman. This satellite is designed to monitor other satellites’ movements in a geosynchronous orbit, approximately 22,300 miles above the equator. At this altitude, satellites remain in sync with Earth’s rotation, appearing stationary from the ground. The GSSAP satellites enhance the ability to detect and analyze disturbances affecting space systems in this critical orbit.
Gary Wentz, ULA’s Vice President for the Atlas and Vulcan programs, noted the significance of this mission, stating, “This is the type of mission that the team actually designed this launch vehicle to support. It’s significant payloads to very complex orbits, multi-manifested national security space, direct-to-geo. So this is tailor-fit for that mission.”
Before the launch, ULA management declined to confirm the number of GSSAP satellites aboard the Vulcan. Additionally, the rocket’s nose cone housed an ESPAStar spacecraft, a deployable platform capable of accommodating multiple payloads. All payloads launched during this mission were classified.
As the mission progressed, ULA emphasized its commitment to advancing capabilities for complex space operations while ensuring the reliability of its launch systems. The challenges faced during this latest flight will be thoroughly analyzed to maintain the integrity of future missions.
