SpaceX’s Starship rocket launches from Starbase during its second test flight in Boca Chica, Texas, on November 18, 2023.Photograph: TIMOTHY A. CLARY/Getty Images
By Ramin Skibba,
Published by Wired, 21 November 2023
A second Starship test flight advanced a bit farther than the first, with the rocket reaching the edge of space but blowing up soon after. Industry experts say it’s still a step forward.
If founder Elon Musk’s vision comes to pass, later this decade SpaceX’s Starship could transport astronauts and private passengers to the moon—and perhaps a decade or two later, to Mars. Last weekend’s second near-orbital test flight of the huge rocket fared better than the first one on April 20, surviving stage separation and crossing the edge of space before it self-destructed about 10 minutes after liftoff.
Saturday’s flight test got off to a promising start. The rocket blasted off smoothly, without hurtling chunks of debris from the launch pad, as had happened during the April launch. SpaceX listed several other technical milestones in an update posted today on the company’s website: Among them, that all 33 Raptor engines worked. (At least six hadn’t worked properly during the April test flight.) Starship then successfully separated from the Super Heavy booster—again an improvement over April, when the stack failed to separate and began to tumble. “This was the first time this technique has been done successfully with a vehicle of this size,” SpaceX officials wrote in their post.
But, this time, after stage separation, the booster detonated over the Gulf of Mexico rather than making a controlled landing. Then near the end of the second-stage burn but before engine cut off, an unknown issue triggered the Starship spacecraft’s automated termination system, exploding it. SpaceX mission control announced it had lost contact with the rocket. (In today’s update, the company did not address what caused the rocket to self-destruct or what caused the lost signal, and it has not responded to WIRED’s requests for comment.) Still, even that was an advance: During the April flight, there was a delay between the termination system’s activation and the actual explosion. This time, the self-destruct system worked correctly. According to the company’s post, the vehicle reached an altitude of about 150 kilometers, “becoming the first Starship to reach outer space and nearly completing its full-duration burn.”
The rocket didn’t last long into its intended 90-minute round-the-world journey, but space industry watchers hailed the flight as a leap forward. “I thought it was fantastic partial success, and really good progress forward. It got some milestones accomplished that needed to happen,” says Laura Forczyk, an Atlanta-based space industry consultant. “Not only SpaceX but also NASA, which is SpaceX’s most important customer, was pleased with the results,” she added, referring to NASA chief Bill Nelson’s praise on social media following the launch. “Spaceflight is a bold adventure demanding a can-do spirit and daring innovation. Today’s test is an opportunity to learn—then fly again. Together @NASA and @SpaceX will return humanity to the Moon, Mars & beyond,” he posted on X.
NASA has tapped SpaceX for its first two moon landings, big contracts worth more than $4 billion for the Artemis 3 and 4 missions. These will involve bringing astronauts to the moon’s surface in 2026 and 2028, more than a half century after the last lunar visitors.
“With a test like this, success comes from what we learn, and today’s test will help us improve Starship’s reliability as SpaceX seeks to make life multiplanetary,” SpaceX officials posted shortly after the launch on X.
Now the question is, what happens next?
Since Starship blew up, the US Federal Aviation Administration is required to oversee SpaceX’s “mishap investigation” to make sure the launch and explosion haven’t created environmental or safety concerns. Immediately following the test, the agency released a brief statement: “The anomaly resulted in a loss of the vehicle. No injuries or public property damage have been reported. The FAA will oversee the SpaceX-led mishap investigation to ensure SpaceX complies with its FAA-approved mishap investigation plan and other regulatory requirements.”
After the April test flight, a similar investigation took almost five months and resulted in the FAA issuing a list of 63 issues SpaceX had to address before Starship could fly again. That included redesigning vehicle hardware to prevent leaks and fires, redesigning the launch pad to increase its robustness, and testing safety systems. The new launch infrastructure then necessitated a review by the US Fish and Wildlife Service to study potential effects on the habitats of threatened or endangered species in the area, which include birds and sea turtles. Finally, the FAA granted the launch license for the second Starship flight—only days before the November 18 launch.
According to the FAA, following the investigation, SpaceX’s subsequent application for a new launch license will involve reviewing environmental concerns, which could include assessing whether a new water-cooled flame deflector system worked as it was supposed to. The system flushes hundreds of gallons of water through steel plates to limit debris and noise pollution without releasing water contaminated with metals. “Just inspected the Starship launch pad and it is in great condition! No refurbishment needed to the water-cooled steel plate for next launch,” Musk wrote on X on November 19, posting photos that showed leftover water on the launchpad.
Next steps for the company will likely include figuring out the cause of Starship’s lost signal, continuing to prepare the spacecraft for reentry, descent, and splashdown, and ensuring the launch infrastructure works as planned, Forczyk says.
This time, SpaceX successfully implemented hot-stage separation, which is also used by Russian Soyuz rockets. In hot-staging, the booster throttles down its engines and the upper stage begins igniting its engines just before, not after, breaking away. That gives the upper stage an extra boost—and thereby a small extra payload capacity—while reducing the complexity of stage separation. But the exhaust from the upper stage needs to escape while it’s still attached to the booster, and engine fire from Starship could damage the booster as well. SpaceX said on its website that Starship successfully executed hot-staging, with the upper stage’s six Raptor engines firing right before it disconnected.
These test flights demonstrate how SpaceX’s development style differs from NASA’s, Forczyk says: While NASA tested every component to perfection before its Space Launch System and Orion spacecraft could launch—with federal agencies, Congress, and the White House looking over the agency’s shoulder—SpaceX improves by launching over and over again, seeking to do better with each effort.
Phil Metzger, a planetary scientist at the University of Central Florida who studies space economics, agrees. “SpaceX follows a development process where they test before they have all the problems solved, and that results in failures. They sometimes get criticized for it, but it’s a proven method that ends up being cheaper and faster,” he says.
Before it can launch again, SpaceX will need another launch license from the FAA, which it can’t get until it completes its current joint mishap investigation. The time between the first and second Starship flights took seven months, thanks to the previous investigation, and SpaceX’s hardware redesigns and launchpad reconstruction—but the third could come sooner. “I think the FAA will have fewer concerns this time, because there was no pad breakage and the explosion happened at a much higher altitude. I think they will give SpaceX a faster green light this time,” says Niloofar Kamran, an aerospace engineer at Cornell College.
However, an ongoing lawsuit by environmental organizations and local groups near the Boca Chica, Texas, launch site could delay the Starship program if it results in the FAA having to complete a new environmental impact statement, a more rigorous and time-consuming review.
SpaceX appears to be targeting early 2024 for its third test flight, based on the company’s filing with the Federal Communications Commission. Musk also wrote on X that the Starship flight hardware would be ready in three to four weeks. Once again, the goal will be to fly almost completely around the world, reenter the atmosphere, and splash down near Hawaii.
SpaceX will need at least a few successful test flights—including an uncrewed lunar landing—before it can put people on board. While returning from Earth orbit is one thing, safely bringing back astronauts from the moon is another. A lunar voyage involves faster reentry speeds and requires a spacecraft that can handle hotter temperatures.
Each Artemis mission will actually require SpaceX to launch many Starships: The plan will be to loft almost 20 of them, each carrying fuel, to fill a propellant depot in Earth orbit. A modified lander version of the spacecraft would then use the depot to fill its tanks and head to its lunar landing spot.
While SpaceX made some progress between the first and second test flights, the Starship engineers have their work cut out for them to make the rocket safe for crewed flights with NASA and private partners. “With each test flight, they are going to have greater standards for themselves, because they really need to move quickly,” Forczyk says.
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