The rocket lifted off at 4:22am Eastern Standard Time on 12 February from Cape Canaveral Space Force Station in Cape Canaveral, carrying the USSF-87 mission for the United States Space Force’s Space Systems Command.
During the initial phase of the launch, engineers detected an unexpected performance issue with one of the rocket’s four solid rocket boosters. Despite the anomaly, United Launch Alliance (ULA) confirmed the launch vehicle’s main booster and upper stage performed as intended and successfully placed the spacecraft directly into geosynchronous orbit.
ULA vice-president for Atlas and Vulcan programs, Gary Wentz, said the company and its government partners were examining flight data and imagery to determine what occurred.
“Early in the flight, the team observed a significant performance anomaly on one of the four solid rocket motors,” Wentz said. “Despite that observation, the Vulcan booster and Centaur upper stage performed nominally and delivered the spacecraft directly to geosynchronous orbit.”
He said a joint government and contractor team is reviewing technical data and imagery while establishing a recovery effort to collect any debris from the affected booster.
“We will conduct a thorough investigation, identify the root cause and implement any corrective actions required before the next Vulcan mission,” Wentz said.
The primary payload aboard the USSF-87 mission is part of the Geosynchronous Space Situational Awareness Program (GSSAP), a satellite system built by Northrop Grumman.
Operating in near-geosynchronous orbit, the GSSAP satellites act as dedicated sensors for the Space Surveillance Network used by United States Space Command. The spacecraft are designed to monitor other satellites operating in the same orbital region, effectively providing a “neighbourhood watch” capability in geostationary orbit.
By improving the accuracy of satellite tracking in the increasingly crowded geosynchronous environment, the system allows space operators to more rapidly warn other spacecraft operators if objects are predicted to approach dangerously close to one another.
The data gathered by GSSAP enhances orbital prediction models and supports safer operations for all nations with satellites operating in geostationary orbit, including improved collision-avoidance planning.
In addition to the primary surveillance spacecraft, the USSF-87 mission also carries several research, development and training payloads.
These systems will allow Space Force personnel known as Guardians to refine tactics, techniques and procedures for precise on-orbit manoeuvres. The experimental payloads will also test technologies designed to improve the resilience and protection of satellites operating in geosynchronous orbit.
The mission marks the second flight of the Vulcan rocket since it achieved certification under the National Security Space Launch program, which authorises the vehicle to carry critical US national security payloads.
The Vulcan Centaur family is intended to replace ULA’s long-serving Atlas V and Delta IV launch vehicles, continuing their role in placing sensitive defence and intelligence satellites into orbit for the US government, including missions for the National Reconnaissance Office.
Since its formation in 2006, ULA has launched more than 100 national security missions for the Space Force and the NRO, building its reputation on the reliability of the Atlas V, Delta II and Delta IV rocket families. That legacy now continues with the next-generation Vulcan rocket, which the company said is purpose-built to support future US defence and intelligence space missions.