Launch Interruption
SpaceX has initiated a temporary halt to its Falcon 9 launch schedule subsequent to an issue that surfaced with the rocket's upper stage at the conclusion
of a mission on February 2nd. This particular Falcon 9 rocket had successfully ascended from Vandenberg Space Force Base in California at 10:47 AM Eastern time. The upper stage performed its primary function, deploying a payload of 25 Starlink satellites into low Earth orbit approximately 62 minutes post-liftoff. This deployment was facilitated by two activations of the stage's solitary Merlin engine. However, about nine hours after the launch concluded, SpaceX reported that the upper stage encountered an "off-nominal condition" as it prepared for a final engine burn intended to deorbit the stage. While the company offered no further details regarding the specific nature of this condition, it did confirm that the stage had functioned flawlessly up to that point, including the successful deployment of its satellite cargo. Following the anomaly, the vehicle executed its programmed safety protocol, described by the company as a normal procedure to 'passivate' the stage. This passivation process typically involves releasing any remaining propellants and discharging onboard batteries to neutralize stored energy, thereby preventing potential breakup events.
Root Cause Analysis
The immediate aftermath of the Falcon 9 upper stage anomaly has seen SpaceX's engineering teams deeply engaged in a thorough data review. The company has stated that its primary objective is to meticulously examine all available information from the recent flight to pinpoint the exact root cause of the "off-nominal condition." This intensive investigation is a critical precursor to defining and implementing appropriate corrective actions. Until this process is fully completed and the findings are satisfactory, SpaceX has made the decision to temporarily suspend all Falcon 9 launches. The duration of this pause has not been specified by the company, leaving some uncertainty regarding the timeline for returning to flight. Looking at the current manifest, the next scheduled Falcon 9 launch was slated for February 5th from Florida, a mission that had been originally planned for February 3rd, indicating a potential adjustment to the launch cadence.
Past Incidents
This recent upper stage issue is not the first time SpaceX has faced challenges with this critical component of the Falcon 9. In September 2024, the Crew-9 mission experienced a significant problem during the upper stage's deorbit burn, leading to an unintended reentry trajectory that placed the stage outside its designated recovery zone in the South Pacific Ocean. That incident necessitated a pause in most Falcon 9 launches for approximately two weeks, pending an acceptance of the company's investigation findings by the Federal Aviation Administration. Another notable occurrence took place in February 2025, when a Falcon 9 upper stage failed to execute its deorbit burn altogether. SpaceX attributed this failure to a propellant leak, and the stage subsequently underwent an uncontrolled reentry over Europe, with some fragments reportedly landing in Poland. Interestingly, this particular event did not result in an extended hiatus for Falcon 9 operations. Furthermore, in July 2024, a Falcon 9 upper stage suffered a complete mission failure when its engine was unable to restart, leaving the stage and its Starlink payloads stranded in a critically low orbit. SpaceX managed to resume launches just 15 days later, following an investigation that identified a liquid oxygen leak as the cause of that failure. Spaceflight analyst Jonathan McDowell observed on February 2nd that the low perigee of the stage suggested an imminent reentry.
