An investigation is underway after a rare inflight failure caused SpaceX's Falcon 9 rocket to be grounded.

• On Thursday evening, SpaceX's Falcon 9 rocket experienced a rare midflight failure while carrying Starlink satellites.
• Elon Musk confirmed that the upper second stage of the rocket failed to reignite its engine as planned and was destroyed.
• The Federal Aviation Administration has not yet approved SpaceX's investigation of the incident, which is why Falcon 9 remains grounded, according to a confirmation from CNBC.

The Falcon 9 rocket of SpaceX is currently grounded due to an inflight failure, which is a rare occurrence for the company's primary vehicle.

On Thursday evening, the "Starlink Group 9-3" mission, which originated from California's Vandenberg Space Force Base, launched with 20 satellites destined for low Earth orbit.

The rocket's first stage functioned as intended and landed safely, but the upper second stage failed to restart its engine and was destroyed, as confirmed by SpaceX CEO Elon Musk.

The upper stage restart to increase perigee resulted in an engine RUD, which is currently unknown, according to Musk's social media post.

The Federal Aviation Administration has confirmed that SpaceX's investigation of the incident with Falcon 9 is ongoing and the rocket remains grounded until the investigation is complete.

SpaceX's final report, including any corrective actions, must be approved by the FAA, who will be involved in every step of the investigation process, according to a statement from the agency to CNBC.

In 2024, SpaceX launched a Falcon 9 rocket every two to three days, making it the 69th launch of the year. However, an investigation may delay upcoming launches, including two crewed missions: Polaris Dawn and Crew-9.

Despite the second stage engine failure, SpaceX successfully deployed 20 Starlink satellites. However, the company noted that the satellites are in a "lower than intended orbit." As of early Friday morning, SpaceX has made contact with five of the satellites and is attempting to use their onboard thrusters to climb higher in orbit to avoid burning up in the atmosphere.

"Musk wrote that they are updating satellite software to operate ion thrusters at their equivalent of warp 9, although "this may not work, but it's worth a try.""

Since its inflight failure in June 2015, during the NASA cargo mission CRS-7, Falcon 9 has been on an unrivaled run of success for nearly a decade, with over 300 consecutive successful orbital launches.

Over 280 times, SpaceX's Falcon 9 has successfully landed more than 300 missions to orbit.