The latest prototype of SpaceX’s Starship launch vehicle — Starship SN10 — took off from the company’s South Texas test site and flew to an altitude of more than 30,000 feet Wednesday, then descended to a controlled vertical landing after two previous test vehicles crashed at touchdown. Minutes later, the 16-story test rocket exploded in a fireball, but the test flight appeared to be a major step forward in the early stages of the Starship program.
The 164-foot-tall (50-meter) Starship prototype lifted off from SpaceX’s test site at Boca Chica, Texas, at 5:14 p.m. CST (6:14 p.m. EST; 2314 GMT) powered by three methane-oxygen Raptor engines generating more than a million pounds of thrust. An earlier launch attempt Wednesday ended in a last-second abort.
The three Raptor engines shut down sequentially as the Starship soared to an altitude of around 32,800 feet, or 10,000 meters, then the final engine shut down to allow the rocket to begin its descent.
The Starship tipped over to a horizontal orientation for a “belly flop” descent, using two forward and two aft flaps to control its flight. Finally, seconds before reaching the ground, the three Raptor engines reignited and flipped the rocket back vertical. Two of the engines shut down seconds later, as planned, and a single throttleable Raptor engine put the rocket into a near-hover as it gently touched down on the landing pad adjacent to the launch site at Boca Chica around 6 minutes, 20 seconds, after takeoff.
A hard landing on an otherwise-successful Dec. 9 Starship test flight was caused by low pressure from header tanks feeding the vehicle’s Raptor engines for the critical burn just before touchdown, and one of the Raptor engines failed to reignite for the landing burn on a test flight Feb. 2.
The Starship SN10 vehicle launched itself again — unintentionally — a few minutes after landing when a huge fireball catapulted the rocket back into the air. Wreckage fell back onto the landing pad.
Despite the explosion, the Starship SN10 test flight appeared to be a major achievement for SpaceX’s Starship test flight program.
“Third time’s the charm as the saying goes,” said John Insprucker, a veteran SpaceX engineer who provided commentary on SpaceX’s webcast of the test flight. “We’ve had a successful soft touchdown on the landing pad, capping a beautiful test flight of Starship 10.”
Insprucker said “a key point of today’s test flight was to gather the data on controlling the vehicle while re-entering, and we were successful in doing so. We had a nominal ascent, we had the maneuver to place Starship horizontal when we reached 10 kilometers, right on time. And then during the sub-sonic entry, it appeared we had good control of the vehicle using the front and aft flaps.”
“As we approached the landing pad, we successfully lit the three Raptor engines to perform that flip maneuver, and then we shut down two of them and landed on the single engine as planned,” Insprucker said. “A beautiful soft landing of Starship on the landing pad at Boca Chica.
The Starship program is SpaceX’s next-generation heavy-lift rocket, and is designed to ferry people and cargo to deep space destinations such as the moon and Mars, according to Elon Musk, SpaceX’s founder and CEO. SpaceX is expanding a rocket manufacturing and test facility at the Boca Chica site. Musk tweeted Tuesday he plans to “create” a city named Starbase, Texas, at the location just north of the U.S.-Mexico border.
“Starship SN10 landed in one piece!” Musk tweeted after Wednesday’s test flight.
“RIP SN10, honorable discharge,” he tweeted after the explosion.
Starship SN10 exploded a few minutes after landing at Boca Chica, Texas.
— Spaceflight Now (@SpaceflightNow) March 3, 2021
Musk and SpaceX did not immediately provide details on what caused the post-landing explosion.
SpaceX is focusing, for now, on testing the 164-foot-tall (50-meter) upper stage of the huge new rocket rocket, which measures around 30 feet (9 meters) wide, about one-and-a-half times the diameter of a Boeing 747 jumbo jet.
That portion of the vehicle is known simply as Starship, while a powerful booster yet to be built is called Super Heavy. The Starship and Super Heavy are both designed for vertical takeoffs and landings, with the Super Heavy detaching a few minutes after liftoff to return to Earth, and the Starship continuing into orbit.
The entire vehicle will stand nearly 400 feet, or about 120 meters, tall and carry more than 100 metric tons, or 220,000 pounds, of cargo to low Earth orbit, more than any rocket in the world. With life support systems and in-space refueling, the Starship could carry heavy cargo and people beyond Earth orbit. SpaceX is of of three industrial teams with a NASA contract to design and refine concepts for a human-rated lunar lander for the space agency’s Artemis moon program.
The Starship team in Texas has “steadily increased the test launch cadence over the course of the program, and have delivered some of the most exciting test flights many of us have seen in a long time,” Insprucker said at the conclusion of SpaceX’s webcast Wednesday.
“A controlled aerodynamic descent with body flaps and vertical landing capability, combined with in-space refilling, are critical to landing Starship at destinations across the solar system where prepared surfaces or runways do not exist, and returning to Earth,” SpaceX said. “This capability will enable a fully reusable transportation system designed to carry both crew and cargo on long-duration, interplanetary flights and help humanity return to the moon, and travel to Mars and beyond.”
The orbital version of the Starship vehicle will have six Raptor engines and a heat shield to survive re-entry back into the atmosphere. The Super Heavy booster will be powered by 28 Raptor engines.
While SpaceX has made much-publicized progress with Starship test flights in Texas, and is building the first prototype for the Super Heavy booster, development of life support systems and orbital refueling technology for long-duration Starship flights into deep space is still in the nascent stages.
“The Texas team has several more sub-orbital test vehicles in build, with No. 11 ready to roll out to the pad in the very near future,” Insprucker said. “It’s an inspiring time for the future of human spaceflight. Thanks for joining us today and we hope you’ll join us for the next test flight of Starship 11.”
SpaceX is developing the Starship to help achieve the company’s ambition of creating a human settlement on Mars.
One of the first customers for the Starship program is Japanese entrepreneur Yusaku Maezawa, who plans to invite eight members of the public on a Starship flight around the moon and back to Earth. His mission, known as dearMoon, would be the first privately-funded human mission beyond Earth orbit, and carry the passengers farther from Earth than any humans in history.
Maezawa announced Tuesday he is requesting applications from the public to join the dearMoon flight, which he said will have 10 to 12 people on-board in total. The mission aims to blast off in 2023.
“I’m highly confident that we will have reached orbit many times with Starship before 2023, and that it will be safe enough for human transport by 2023,” Musk said. “It’s looking very promising.”
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