SpaceX Falcon 9 second stage engine suffers catastrophic in-flight failure during Starlink launch

SpaceX has launched another batch of Starlink California’s internet satellites lifted off Thursday, but the engine powering the rocket’s second stage suffered a catastrophic failure or even an explosion during an attempt to perform a final “burn” to raise the low point of the orbit, the company’s founder said. Elon Musk published early Friday on X.

Elon Musk called the anomaly “RUD,” a tongue-in-cheek acronym that stands for “rapid, unscheduled disassembly.”

“The upper stage restart to raise perigee resulted in an engine RUD for reasons currently unknown,” he said on X. “The team is reviewing the data tonight to understand the root cause. The Starlink satellites have been deployed, but the perigee (lowest orbital point) may be too low for them to raise the orbit. We will know more in a few hours.”

SpaceX later said that flight controllers had made contact with five of the 20 Starlinks launched Thursday “and were attempting to lift them into orbit using their ion thrusters.”

Musk added that the Starlink team was busy “updating the satellite’s software to run the ion thrusters at their equivalent of warp 9. Unlike a Star Trek episode, this probably won’t work, but it’s worth a try. The satellites’ thrusters need to raise their orbit faster than atmospheric drag pulls them down, or they burn up.”

The malfunction could impact plans to launch entrepreneur Jared Isaacman and three crew members later this month aboard a Falcon 9 for a commercial flight that is set to include the first spacewalks by non-government astronauts. It could also impact NASA’s plans to launch a new crew to the International Space Station aboard a SpaceX Crew Dragon capsule around Aug. 19.

Given SpaceX’s high flight rate and ability to launch its own payloads (Starlinks), the company may be able to recover fairly quickly. But that remains to be seen.

The Falcon 9, whose first stage was making its 19th flight, lifted off from Pad 4E at Vandenberg Space Force Base northwest of Los Angeles at 10:35 p.m. EDT, climbing through thick fog on a southerly trajectory. Two and a half minutes later, the first stage dropped off and flew to a successful drone ship landing while the second stage continued its ascent toward space.

Starlink launches require two firings of the second stage’s Merlin vacuum engine. The first firing completed on schedule, about eight and a half minutes after liftoff.

Live video from onboard cameras showed spectacular images of the second stage’s first “burn,” with the engine nozzle glowing against the dark backdrop of space. The cameras also showed unusual accumulations of ice on the side of the rocket, as well as a steady stream of cold clumps breaking off and vaporizing in the engine’s fiery but transparent exhaust.

Ice buildup on rockets is not unusual, but the amount seen during Thursday’s launch was much greater than that seen during previous flights, likely indicating a problem of some kind.

But in accordance with SpaceX’s policy regarding Starlink launches, the live video and comments posted on the X social media platform ended after the second stage 1 engine was confirmed to have shut down, approximately eight minutes and 40 seconds after liftoff.

The company typically releases confirmation of payload deployment after a final one-second burn of the second stage engine to raise the low point of orbit. That burn occurs about 45 minutes after the first burn is complete, followed by payload deployment about seven minutes later, or about 59 minutes after launch. But no such confirmation has been posted on X. Musk’s tweet came at 12:35 a.m.

The Falcon 9 rocket is one of the most reliable in the world. Thursday’s launch was SpaceX’s 69th Falcon 9 flight this year and 354th since the rocket’s debut in 2010. Before the latest launch, SpaceX had completed 344 consecutive successful Falcon 9 flights after the company’s only flight failure in 2015.

Before Thursday’s flight, SpaceX had launched 6,720 Starlinks on 181 Falcon 9 flights, about 6,200 of which were presumed operational, according to Jonathan McDowell, an astrophysicist and space statistician. Losing a batch of Starlinks wouldn’t be a major setback for SpaceX, but it would undoubtedly interrupt the company’s rapid launch streak.

Company officials said earlier this year that they hoped to launch more than 140 flights this year. Find out more in the video below from the SpaceX Starlink launch in January: