SpaceX Submits FAA Mishap Report, Falcon 9 Set For Return To Flight

SpaceX has submitted its mishap report to the Federal Aviation Administration (FAA) regarding the Falcon 9 launch anomaly that occurred on July 11, 2024.

This report follows a thorough investigation by SpaceX's team, under the supervision of the FAA, with the support of NASA, which identified the probable cause of the incident and the necessary corrective actions to ensure the success of future missions.

During post-flight data reviews, it was confirmed that Falcon 9’s first stage booster performed nominally through its ascent, stage separation, and a successful droneship landing. However, during the first burn of Falcon 9’s second stage engine, a liquid oxygen leak was detected within the insulation around the upper stage engine.

THE ISSUE

The investigation revealed that the leak was caused by a crack in a sense line for a pressure sensor connected to the vehicle’s oxygen system. This crack developed due to fatigue from high engine vibration and looseness in the clamp that normally secures the line.

Despite this issue, the second stage engine continued to operate through its first burn and successfully entered the intended elliptical parking orbit after engine shutdown.

The mission plan included a second burn of the upper stage engine to circularize the orbit before satellite deployment. Unfortunately, the liquid oxygen leak caused excessive cooling of engine components, particularly those involved in delivering ignition fluid to the engine. This led to a hard start rather than a controlled burn, damaging the engine hardware and causing the upper stage to lose attitude control.

Despite this setback, the second stage still managed to deploy the Starlink satellites and complete stage passivation, which involves venting stored energy on the stage—a standard procedure for every Falcon mission.

After deployment, the Starlink team contacted 10 of the satellites to issue early burn commands to raise their altitude. However, the satellites were in a high-drag environment with a very low perigee of only 135 km above Earth. Consequently, all 20 Starlink satellites from this launch re-entered the Earth's atmosphere.

By design, Starlink satellites fully demise upon reentry, posing no threat to public safety, and no debris has been reported following the successful deorbit of these satellites.

THE SOLUTION

In response to the incident, SpaceX engineering teams conducted a comprehensive review of all SpaceX vehicles and ground systems to ensure a safe return to flight. For near-term Falcon launches, the failed sense line and sensor on the second stage engine will be removed.

The sensor, not critical to the flight safety system, can be substituted with alternate sensors already present on the engine. This design change has undergone rigorous testing at SpaceX’s rocket development facility in McGregor, Texas, with enhanced qualification analysis overseen by the FAA and the SpaceX investigation team.

Additionally, an inspection and replacement of sense lines and clamps across the active booster fleet have been carried out proactively in select locations.

"Safety and reliability are at the core of SpaceX’s operations...It would not have been possible to achieve our current cadence without this focus, and thanks to the pace we’ve been able to launch, we’re able to gather unprecedented levels of flight data and are poised to rapidly return to flight, safely and with increased reliability. Our missions are of critical importance – safely carrying astronauts, customer payloads, and thousands of Starlink satellites to orbit – and they rely on the Falcon family of rockets being one of the most reliable in the world. We thank the FAA and our customers for their ongoing work and support." - SpaceX

SpaceX is committed to implementing the lessons learned from this incident to improve the reliability and safety of future missions, ensuring that the Falcon 9 continues to be a dependable vehicle for space exploration and satellite deployment.

Watch the first Falcon 9 launch in weeks, targeting no earlier than this Saturday LIVE on TLP

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