This morning, was set to make its biggest test yet: Liftoff from the company’s Starbase launch site in Texas, with reentry and splashdown in Hawaii. At first, things were going well—the rocket did manage to leave its launchpad in Boca Chica. Then, things went sour quickly, culminating in a massive midair explosion.

After launch, a readout on marked a number of engine failures on the rocket. Starship’s first stage, called the Super Heavy Booster, uses an arrangement of 33 SpaceX Raptor engines—three of which failed at or before launch. During the rocket’s brief flight, two more engines burnt out, bringing the total to five.

Minutes into the flight, Starship began to rotate in the air, falling into a spin. Commentators on SpaceX’s stream said that, by this point, the Starship flight could no longer be considered a “nominal situation.” They also stated that the Super Heavy booster should have separated by this point in the flight.

Then, three minutes and 59 seconds into the flight, Starship detonated into a ball of flame. Commentators on postulated that the rocket may have been intentionally scrubbed, using an “automated flight termination system,” but SpaceX commentators described the situation as “rapid unscheduled disassembly.” It’s not clear if that quip meant that the automated termination system did engage, or if something worse happened within the Starship system.

As a test flight, this was still a success for SpaceX. The Starship system hadn’t before cleared its launch pad under the power of the Super Heavy booster, and the data SpaceX gained from the flight is likely irreplaceable. Still, they likely would’ve preferred if it hadn’t blown up.