Running two days late, SpaceX launched its huge Super Heavy-Starship rocket Tuesday, chalking up what appeared to be a remarkably successful test flight in the wake of three back-to-back failures earlier this year.
While re-entry heating damaged a protective “skirt” around the the engine bay of the upper stage Starship, along with partially melting a control flap near its hinge, the vehicle remained under control throughout and made it all the way to a powered splashdown in the Indian Ocean as planned.
“Splashdown confirmed! Congratulations to the entire SpaceX team on an exciting tenth flight test of Starship!” SpaceX said in a post on X.
Earlier, the Super Heavy first stage also performed as planned, boosting the Starship out of the lower atmosphere, then flying itself back toward the Texas Gulf Coast for an off shore splashdown.
In a test, one of the engines used during a powered descent was deliberately shut down, but the booster compensated and the rocket, falling tail first, dropped into the Gulf as planned.
SpaceX workers in Texas and California cheered and applauded major milestones throughout the one-hour six-minute test flight, expressing their obvious elation after three catastrophic failures in a row leading up to Tuesday’s 10th test flight
The mission began when the Super Heavy’s 33 methane-fueled Raptor engines flashed to life with a ground-shaking roar and a rush of flaming exhaust at 7:30 p.m. ET, majestically pushing the 40-story-tall rocket away from SpaceX’s Starbase facility on the Texas Gulf Coast.
A launch try Sunday was called off because of trouble with ground equipment and a second attempt Monday was blocked by cloudy weather.
But it was clear sailing Tuesday as the rocket, the most powerful ever built, put on a spectacular show accelerating toward space atop some 16 million pounds of thrust — more than twice the power of NASA’s Space Launch System moon rocket and the agency’s legendary Saturn 5.
Given the Super Heavy-Starship’s uneven track record to date, concern has been growing that a moon lander variant of the Starship being built for NASA may not be perfected in time for a planned 2027 landing and possibly not before the Chinese plant their own flag on the moon at the end of the decade.
The success of Tuesday’s flight will not ease those concerns — a multitude of technical hurdles remain — but it was no doubt a shot in the arm for company founder Elon Musk and the SpaceX workforce.
The initial stages of the test flight went smoothly. One of the booster’s 33 engines shut down prematurely, but the 230-foot-tall Super Heavysuccessfully propelled the Starship upper stage out of the lower atmosphere. It then separated, flipped around and flew itself to a splashdown off the Texas Gulf Coast as planned.
The stage is designed to fly itself back to its launch gantry for a mid-air capture by giant mechanical arms, a feat pulled off three times during earlier testing.
But for Tuesday’s flight, the booster targeted the Gulf while flight controllers monitored how it performed when an engine used for landing were deliberately shut down to simulate a failure. The stage appeared to compensate as required.
The Starship upper stage, meanwhile, flew into a sub-orbital trajectory as planned, a milestone the three previous test flights failed to achieve.
Over the next 38 minutes or so, the Starship successfully deployed eight Starlink satellite simulators to test the Pez-like deployment mechanism and briefly re-ignited of one of the rocket’s six Raptor engines to verify it’s ability to restart in space.
Then, during re-entry into the lower atmosphere, new heat shield tiles were put to the test while cameras and other sensors monitored how the extreme temperatures of re-entry affected various structures.
A protective skirt around the base of the engine compartment appeared to break apart as the heating intensified and at least one flap, used to control the Starship’s orientation in the atmosphere, partially melted near a hinge connecting it to the fuselage.
But it appeared to work normally throughout, flipping back and forth on command as the flight computer executed a series of tests.
Like the Super Heavy booster, the Starship is designed to fly itself back to a launch gantry for mid-air capture. But SpaceX has not yet attempted a return-to-launch-site with a Starship, and the rocket instead descended to an on-target splashdown in the Indian Ocean.
The company positioned a camera buoy in the area before launch and it captured fleeting views of big rocket, its skin blistered as expected during re-entry, falling tail first to “landing.” It then broke up and exploded, but that was expected with a water landing.
A successful test flight was critical to SpaceX, which wants to work the bugs out as soon as possible and get the rocket flying on operational missions to launch scores of Starlinks and other satellites and eventually to carry settlers and equipment to Mars.
The test flights also are critical to NASA, which is counting on a modified version of the Starship to carry two astronauts to the moon’s surface as early as 2027.
Because the rocket if fully reusable, the moon lander will use all of its propellant just reaching low-Earth orbit. To send it to the moon, SpaceX will need to launch 10-to-20 Superheavy-tanker flights to re-fill the lander’s tanks with the needed propellant.
It also will need to somehow counteract the natural warming of the liquid oxygen and methane fuel that otherwise will cause the propellants to “boil off,” turning into a gas that must be vented overboard.
No orbit-class rockets have ever demonstrated the sort of rapid-fire launch cadence that will be required or carried out the autonomous transfer of thousands of gallons of cryogenic propellants from one rocket to another in the weightless environment of space amid extreme temperature swings.
A single launch failure almost certainly would result in cancellation of a moon mission while an investigation ran its course. And an explosive failure in low-Earth orbit would result in a huge cloud of dangerous debris.
Safely landing on the moon with a 16-story-tall rocket presents its own challenges, not least of which is the possibility of uneven terrain or loosely packed soil that could result in a tip over. And the astronauts will have to ride an external platform down to the surface 100 feet or so below the upper crew section.
Most observers believe SpaceX will eventually overcome those hurdles. The question is, can the company do it in time for a 2027 moon landing? Or if not, will the rocket be ready to carry astronauts to the moon before the Chinese plant their own flag on the surface by the end of the decade?
CBS News interviewed multiple current and former NASA and contractor managers and engineers in recent weeks who unanimously agreed a landing in 2027 could not be safely carried out with the current HLS architecture.
And not one of them said they believed NASA could get there before the Chinese without a drastic change of course.
“I think the folks you’ve talked to are accurate. We are not going to go ahead and get a crewed Starship to the moon by 2030, under any circumstances,” said a senior engineer who worked on the Artemis program.
“That doesn’t mean they’ll never get there. That doesn’t mean the architecture couldn’t work. But it’s just too big of a technical leap to accomplish in the short time that we’ve got.”
source: spaceflightnow.com