SpaceX Starship test vehicle explodes moments after test-firing

A full-size prototype of SpaceX’s Starship violently exploded in South Texas moments after a test-firing of its Raptor engine Friday, dealing a setback to the company’s next-generation reusable rocket program.

The fiery explosion at SpaceX’s test site at Boca Chica, just east of Brownsville near the U.S.-Mexico border, occurred at 1:49 p.m. CDT (2:49 p.m. EDT; 1849 GMT) Friday, around two minutes after a brief firing of a Raptor engine mounted to the base of the Starship vehicle.

SpaceX typically evacuates the area around the test site for engine hotfires, and there were no reports of injuries Friday.

A cloud of vapors suddenly appeared around the bottom of the Starship vehicle — made of stainless steel — moments after the Raptor engine appeared to complete a normal test-firing that lasted a few seconds. Vapors were also visible streaming from vents higher up on the Starship vehicle before the explosion.

The Starship was loaded with cryogenic methane and liquid oxygen propellants for Friday’s test.

The fire appeared to originate near the base of the rocket, and the Starship was nearly instantaneously engulfed in a fireball. Multiple live webcams aimed at the Starship showed debris from the rocket falling around the test stand, which also appeared to sustain damage.

The explosion occurred one day before a separate SpaceX team at the Kennedy Space Center in Florida plans a second launch attempt for the company’s first spaceflight with humans aboard a Falcon 9 rocket and Crew Dragon spacecraft. An earlier try was scrubbed Wednesday due to bad weather.

The Starship is SpaceX’s next-generation spaceship. The company intends for the Starship and its booster rocket, called the Super Heavy, to eventually replace the Falcon 9 and Dragon vehicles.

The loss of another Starship vehicle Friday marked the fourth time a Starship test vehicle destroyed during ground testing in a little more than six months.

An initial Starship prototype ruptured during cryogenic pressure testing at Boca Chica last November, less than two months after SpaceX founder Elon Musk hosted a presentation at the South Texas test site provide an update on the company’s Starship plans.

Speaking to reporters and space fans last September, Musk suggested the first Starship prototype could perform a high-altitude atmospheric test flight before the end of 2019.

But SpaceX has since refined the Starship design and introduced improved manufacturing techniques to address structural deficiencies.

A second Starship test rocket crumpled during another pressure test in early March, and a third one collapsed during a similar cryogenic loading test April 3. Friday’s accident was the first Starship mishap to occur in conjunction with a Raptor engine test.

But SpaceX quickly moved on to the next Starship prototype as part of the company’s fast-paced iterative development process. Additional Starships are already in production for the next stage of testing at Boca Chica for the next stage of testing.

The fourth full-size Starship vehicle, which was destroyed Friday, passed the cryogenic pressure test milestone April 26. SpaceX then installed a Raptor engine on the bottom of the vehicle and conducted a test-firing May 5, then performed a series of additional hotfire tests throughout May leading up to Friday’s Raptor test-firing.

The tests were leading up to a hop test of the Starship vehicle as soon as next week. A temporary flight restriction closing airspace over the Boca Chica test site to an altitude of 26,000 feet (7,900 meters) was in place for Monday, June 1, suggesting SpaceX might attempt a low-altitude test flight of the Starship on that date.

The Federal Aviation Administration issued a launch license Thursday for SpaceX to conduct suborbital test flights of the Starship prototype at Boca Chica, clearing a major regulatory hurdle before the company proceeds into the next phase of flight testing with a full-size Starship vehicle. A sub-scale Starship prototype flew last August on a hop to an altitude of 500 feet (150 meters), then translated to a nearby landing pad, where it descended vertically and touched down.

The Starship is one of two components of SpaceX’s next-generation reusable launch system, which the company says will be the most powerful rocket ever built. Future Starship vehicles will be joined with a Super Heavy booster, which SpaceX is also developing, to loft massive payloads into Earth orbit, to the moon, Mars and other deep space destinations.

The privately-developed Starship vehicle stands around 164 feet (50 meters) tall with its nose cone installed. The nose cone, which includes aerodynamic fins, was not on the rocket for Wednesday’s test. The vehicle measures around 30 feet (9 meters) in diameter, about one-and-a-half times the diameter of a Boeing 747 jumbo jet.

Combined with the Super Heavy first stage, the entire stack will stand around 387 feet (118 meters) tall. The Super Heavy will be powered by more than 30 Raptor engines, according to SpaceX.

An operational Starship could haul more than 100 metric tons, or 220,000 pounds, of cargo to low Earth orbit, SpaceX said.

“Starship has the capability to transport satellites, payloads, crew, and cargo to a variety of orbits and Earth, lunar, or Martian landing sites,” SpaceX wrote in a Starship user’s guide released earlier this year.

NASA awarded SpaceX a $135 million contract April 30 to advance steps to demonstrate the feasibility of using a Starship variant to land astronauts on the moon as part of the space agency’s Artemis program. NASA also awarded lunar lander contracts to industrial teams led by Blue Origin and Dynetics.

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