On July 11, 2024, SpaceX’s Falcon 9 rocket experienced a significant anomaly during a mission to deploy 20 Starlink satellites. This incident led to the grounding of all Falcon 9 rockets by the Federal Aviation Administration (FAA). A similar grounding occurred in August 2024 and most recently in late September 2024. After investigation was completed and corrective measures in place, FAA cleared SpaceX to resume the launches. This report delves into the details of the anomaly, the subsequent grounding, the FAA’s findings, and the solutions implemented by SpaceX to return the Falcon 9 to service.

The Anomaly and FAA

In July 2024, the Falcon 9 rocket launched from Vandenberg Space Force Base in California, carrying a payload of 20 Starlink satellites. The launch initially went ahead as planned, with a successful first stage separation. However, during the second stage of the flight, the rocket’s upper stage engine did not ignite. This failure was attributed to a crack in a “sense line” for a pressure sensor, leading to a liquid oxygen leak [1] [2].

On August 2024 mission, the Falcon 9 booster B1062 experienced a failure during its landing attempt on the drone ship “A Shortfall of Gravitas.” The booster tipped over and exploded upon landing, ending a streak of 267 successful landings. The exact cause of the failure is still under investigation, but it was noted that a green flash was seen around the Merlin engines before the explosion.

During the September 2024 Crew-9 mission, the Falcon 9’s second stage experienced an “off-nominal deorbit burn,” causing it to land outside the designated safety zone in the Pacific Ocean. The deorbit burn is designed to target the re-entry of the upper stage to dispose it of over an unpopulated region of the ocean. The exact cause is still under investigation.

The FAA swiftly responded to these incidents by grounding all Falcon 9 rockets. This decision was made to ensure public safety and to allow for a comprehensive investigation into the cause of the failure. The FAA said that the rockets would remain grounded until SpaceX could demonstrate that the issue had been resolved and that future launches would not pose a risk [2]. The agency announced that it would be involved in every step of the investigation, working closely with SpaceX to identify the exact cause of the failure and to implement corrective measures [2].

Before the July 2024 launch, the rocket had enjoyed a remarkable string of 344 successful flights since its last major failure in 2015 [2]. SpaceX’s strong track record and its ability to quickly address technical issues were seen as positive indicators and the company was able to resume launches in a matter of weeks [1].

SpaceX’s Investigation, Findings and Solution
SpaceX immediately began an internal investigation to determine the root cause of the anomaly. Preliminary findings suggested that the failure was due to a liquid oxygen leak caused by a crack in a pressure sensor line [1]. This leak led to the buildup of ice near the engine, which ultimately caused the engine to fail during the second stage of the flight [2].

They found that the crack in the sense line was due to a loose clamp and the strain from engine vibration [3]. To address this, SpaceX removed the failed sense line and sensor on the second stage engine for near-term Falcon 9 launches. This design change was tested at their rocket development facility in McGregor, Texas, ensuring that the new configuration would prevent similar issues in future launches.

FAA Clearance and Return to Service

FAA cleared SpaceX to resume Falcon 9 launches, stating that no public safety issues were involved in the anomalies. The FAA’s decision allowed the Falcon 9 to return to flight operations while the overall investigation remained open, provided all other license requirements were met [3].

SpaceX’s rapid response and implementation of corrective measures were key factors in the quick turnaround. The company’s strong track record and focus on safety and reliability were also highlighted as reasons for the expedited clearance [3].

Impact on SpaceX and Implications for Aerospace Industry

The grounding of the Falcon 9 rockets had immediate and far-reaching implications for SpaceX. Several high-profile missions were put on hold, including the crewed Polaris Dawn mission and a NASA mission to resupply the International Space Station (ISS) [2]. The delay of these missions not only affected SpaceX’s schedule but also had a ripple effect on its partners and customers.

The grounding of the Falcon 9 rockets highlighted the inherent risks and challenges associated with space exploration and satellite deployment. It served as a reminder that even the most reliable and well-tested systems can experience failures. This incident underscored the importance of rigorous testing, continuous monitoring, and prompt corrective actions to ensure the safety and success of space missions.

For the aerospace industry, the grounding of the Falcon 9 rockets was a sobering event. It prompted other companies and regulatory bodies to re-evaluate their own safety protocols and contingency plans. The incident also sparked discussions about the need for greater transparency and collaboration between private companies and regulatory agencies to enhance the overall safety and reliability of space missions.