May 27 (UPI) — The Federal Aviation Administration on Wednesday ordered SpaceX to investigate why a booster for its Starship rocket system failed during a test flight Friday, grounding the megarocket for a time.

The FAA declared the incident a “mishap” that involved the Super Heavy first-stage booster as it separated from the main ship and returned to the Gulf of Mexico after launch. The booster was supposed to perform a sustained burn to a controlled landing in the gulf, but a possible engine failure meant it fell back to Earth instead in a “hard splashdown,” SpaceX said in its launch report. The FAA said there were no reports of public injury or damage to public property from the mishap.

“The FAA will oversee the SpaceX-led investigation, be involved in every step in the process, and approve SpaceX’s final report, including any corrective actions,” the agency statement said.

“A mishap investigation is designed to enhance public safety, determine the root cause of the event, and identify corrective actions to avoid it from happening again,” the statement continued. “A return to flight of the Starship-Super Heavy vehicle is based on the FAA determining that any system, process, or procedure related to the mishap does not effect public safety.”

This means that another launch is less likely before the company’s planned initial public offering in June, TechCrunch reported.

The Starship system has two parts: the Super Heavy booster and the spacecraft itself, also called Starship. This was the first launch of the third version of the system, which is the first capable of deep-space flight. Plans call for Starship to carry Artemis 4 astronauts to the surface of the moon in a mission set for late 2028.

The Starship portion of the overall system did make it to space during this test launch, although it also lost one of its Raptor 3 vacuum engines there. Overall, this and other portions of the launch, including deployment of satellites and simulators, were considered a success.