This means SpaceX will have to pause any further Starship test launches until the investigation is completed and the results are submitted to the FAA for approval, diminishing the chance that another will occur before the company’s anticipated IPO in mid-June.

SpaceX did not immediately respond to a request for comment.

“After a thorough assessment of the operation, the FAA has determined the May 22 SpaceX Starship Flight 12 launch resulted in a mishap. The mishap involved the Super Heavy booster as it flew back to the Gulf of America after stage separation. There are no reports of public injury or damage to public property,” the FAA wrote. “The FAA will oversee the SpaceX-led investigation, be involved in every step of the process, and approve SpaceX’s final report, including any corrective actions. ”

The problem with the Starship booster occurred a few minutes into the flight, which was the first launch of SpaceX’s upgraded version of its super heavy rocket system. The first “V3” Starship made it through the point of maximum dynamic pressure and into space, where the booster was supposed to separate from the ship and return to the Gulf for a simulated landing in the water.

The booster did separate from the ship. But it immediately experienced an apparent engine failure — or a possible series of engine failures — when it tried to perform the sustained burn that is meant to propel the booster back toward SpaceX’s launch site in South Texas. This led to the booster tumbling down towards the Gulf before most likely exploding on impact.

SpaceX made a plethora of changes to how Starship works in this third version, with the intention of making the rocket far more reliable than it was in the previous 11 test flights. That included tweaks to the design of the booster, the inclusion of all-new third-generation Raptor engines, and upgrades to the Starship vehicle itself.

Starship experienced its own failure after the booster separated, as it lost one of its six raptor engines. This contributed to SpaceX abandoning one of its testing goals for the flight, which was to do another sustained burn in orbit with Starship.

SpaceX expects its rockets to fail in various ways during this development process, though the goal is to ultimately create a vehicle like the Falcon 9 that becomes not only reliable, but incredibly reusable. Making reusable rockets is crucial to lowering the costs associated with sending heavy payloads to space. As it detailed in its IPO filing, SpaceX is thoroughly reliant on Starship becoming reliable and reusable in order to continue growing its Starlink service, which is by far the company’s biggest revenue generator and currently its only profitable business.

The FAA has ordered SpaceX to perform multiple mishap investigations during the development of Starship. The federal agency also ordered SpaceX rival Blue Origin to perform them as that company develops its own heavy-lift rocket, New Glenn.

Just last week, the FAA cleared New Glenn to fly again. Blue Origin is expected to perform the fourth New Glenn launch attempt in the next month or so.