One of the reasons SpaceX didn’t attempt an orbital flight this week is because it failed one of Starship’s test goals in its last launch, when the spacecraft had to ignite one of its six Raptor engines for a brief burn in space. The spacecraft skipped burn after the Raptor engine shut down prematurely during the launch sequence.
The rest of the ship’s flight went according to plan, culminating in a splashdown in the Indian Ocean. It was the first flight of SpaceX’s Starship V3, debuting its new, more powerful Raptor engines. But officials need confidence in the Raptor engine’s ability to reignite in the airless vacuum of space before it can begin an orbital flight. In a worst-case scenario, a failed Raptor engine burnout could throw the Starship into orbit, sending the giant stainless steel vehicle into an uncontrolled re-entry, endangering public safety.
The flight plan for this week’s mission includes an unfulfilled Raptor restart goal in May. In an update posted on its website over the weekend, SpaceX did not address what caused the Raptor engine to shut down prematurely on Flight 12.
“The vehicle was able to demonstrate its propulsion capability and reach the planned suborbital trajectory,” the company wrote on its website. “A number of hardware and operational modifications have been made to address the interrelated causes with additional reliability improvements planned for future versions of the Raptor engine.”
Another aborted mission on Starship’s last flight was the bounce of the rocket’s Super Heavy booster, or first stage, which lost moments of control as it separated from the ship or upper stage moments after liftoff. SpaceX was designed to fly the booster from a launch base in South Texas from a low-range landing in the Gulf of Mexico.
“During stage separation on Flight 12, slight differences in engine actuation onboard caused the booster directional drift to be off by about 90 degrees,” SpaceX writes. “The startup sequence has been modified to be more robust to timing variability and more reliably convert to any given direction to improve overall performance.
