SpaceX's Ninth Starship Test Flight Delivers Mixed Results

Scientific American

28-05-2025

In its ninth test flight, SpaceX 's launch vehicle Starship once again reached space, surpassing problems that prematurely ended its two previous test launches. But as with those ill-fated preceding flights, in this one, Starship still failed to reach the ground intact. Instead the vehicle spun out of control and disintegrated during atmospheric reentry.
Although each Starship test thus far has succeeded in demonstrating powerful new technical advances that are crucial for the program's further progress, this marks the third flight in a row in which the titanic vehicle suffered a 'rapid unscheduled disassembly' that sent fiery debris cascading down to Earth. All that effort, it's hoped, will prove worthwhile if or when Starship enters regular operations because SpaceX aims to make the vehicle, by far, the largest and most capable fully reusable spacecraft ever flown.
In the latest test, around 50 minutes after launch, SpaceX confirmed that Starship met its demise. At first, everything in the vehicle's flight appeared to be going well. Starship —a 40-story-tall 'stack' that is composed of a giant, 33-engine Super Heavy booster and a 171-foot-long spacecraft powered by six additional engines—lifted off as planned from SpaceX's launch site in Starbase, Tex., at 7:37 P.M. EDT on Tuesday. But cheers were somewhat subdued until about 10 minutes after launch—when operators officially determined that the spacecraft's trajectory was nominal, taking it on a ballistic suborbital path through outer space.
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'Ship engine cutoff—three most beautiful words in the English language,' declared Dan Huot, a communications manager at SpaceX, during the company's livestream of the flight test near the launch site. Around him, sighs of relief could be heard as SpaceX employees began to ascertain that the day's flight would not be a repeat of the previous two, each of which had resulted in the vehicle exploding over the Atlantic Ocean less than 10 minutes after launch.
Around 18 minutes after Tuesday's launch, however, issues began to emerge. First, operators decided not to deploy Starlink satellite demonstrations as planned because of a stuck payload door. Then, about a half an hour after launch, SpaceX mission control reported that suspected propellant leaks were driving the vehicle into a spin, which doomed it to burn up in the atmosphere during reentry—raining debris over the Indian Ocean.
'We're not going to get all of that reentry data that we're still really looking forward to,' Huot admitted in the livestream. 'This is a new generation of ship that ... we're really trying to put through the wringer, as there's a whole lot we still need to learn.'
Meanwhile, although the Starship vehicle itself showed improved performance, the Super Heavy booster that helped it reach space ran into problems of its own. Moments after firing its engines to come in for a landing in the Atlantic Ocean, the booster instead broke apart. This wasn't entirely unexpected; in keeping with SpaceX's 'test to failure' approach, the Super Heavy had attempted to reenter in a different, potentially fuel-saving orientation that subjected the booster to more intense aerodynamic forces. Despite its unplanned disassembly, the booster did mark a significant milestone for SpaceX: for the first time, it flew with a nearly full suite of flight-proven engines that were previously used during Starship's seventh test.
And the booster remains a marvelous demonstration of SpaceX's innovation; a Super Heavy previously made spaceflight history when it became the first rocket ever to be caught in midair with two mechanical arms. In the new launch, the Super Heavy was able to do its intended jobs of bringing Starship to space and testing new reentry techniques, explained Jessie Anderson, SpaceX's senior manufacturing engineering manager, during the flight's livestream.
'There's always a chance we don't reach every objective that we set for ourselves,' Anderson added, 'but success comes from what we learn on days like today.'
On X, former NASA deputy administrator Lori Garver praised SpaceX's transparency but noted these were 'not the results we were hoping for.' Garver was instrumental in forging the space agency's partnership with SpaceX, which helped spark the company's unprecedented dominance of commercial launch services upon which NASA now heavily relies.
Starship is the prized cornerstone of SpaceX's ambitious plan to build human settlements on Mars and is also slated to ferry crews to the lunar surface in a couple of years for NASA's Artemis III mission. Given the high stakes for the vehicle, its test program's mixed results are disappointing, to say the least. Notably, the previous two attempts, Flights 7 and 8, each ended with two spectacular explosions over the Atlantic Ocean. For Flight 8 in particular, the engines shut down unexpectedly minutes after launch, causing the spacecraft to essentially fall apart and self-destruct in midair. SpaceX received some public backlash after the spacecraft debris, which the company claimed would pose minimal risks, led to multiple midflight diversions for passenger airplanes that were under threat.
Nevertheless, SpaceX appeared stalwart and even optimistic about Flights 7 and 8, calling the latter's mishap an ' energetic event ' that occurred because of hardware complications. Last week the company said both explosions had a ' distinctly different ' cause. And in a press release that followed the launch of Flight 9, it noted that Flight 8 greatly informed the upgrades and modifications to Starship for the latest test.
'Developmental testing by definition is unpredictable,' SpaceX said in a prelaunch press release for Flight 9. 'But by putting hardware in a flight environment as frequently as possible, we're able to quickly learn and execute design changes as we seek to bring Starship online as a fully and rapidly reusable vehicle.'
What does Starship's questionable status mean for SpaceX's long-touted goal of ' making life multiplanetary '? If anything, it suggests the company's projections for the vehicle's regular, routine operation have been and remain unrealistically optimistic.
Last year SpaceX founder Elon Musk stated in a social media post that the company plans to launch 'about five' uncrewed Starships to Mars in two years. In another post shortly after Flight 9's mixed results, he touted the vehicle's partial success and predicted that the next few flights would occur at a fast pace of about one per month. Whether or not such haste is feasible, it would certainly be desirable, given the pressure SpaceX faces to deliver on its lofty promises.