The Starship SN10 spacecraft touched down successfully after a high-altitude test flight on March 3, a major milestone for the company and its crewed Mars ambitions. But the vehicle didn’t manage to hold itself together, exploding about eight minutes after landing.
Starship SN10 consists of two elements: a 165-foot-tall (50 meters) spacecraft called Starship and a giant rocket known as Super Heavy, both of which are designed to be fully and rapidly reusable. Both will be powered by SpaceX’s next-generation Raptor engine, six for Starship SN10 and about 30 for Super Heavy, Musk has said.
SpaceX is iterating toward the final Starship SN10 spacecraft via a series of increasingly complex prototypes. For example, the first Starships to get off the ground were single-engine vehicles that flew about 500 feet (150 m) high. SN8, SN9 and Starship SN10 all sported three Raptors, as well as forward and rear flaps for aerodynamic control, so they flew much higher.
Starship SN10 put those flaps to use today as it soared through the South Texas skies. The vehicle performed a number of precise in-flight maneuvers, including a sustained hover at the 6.2-mile maximum altitude, a horizontal descent and a dramatic “landing flip” to get itself vertical in time for touchdown.
Starship SN10 then transferred propellant from the main tanks to the header tanks, before flipping itself for the “belly flop” reentry maneuver – which gives it a controlled descent through the air with the rocket’s four flaps. Then, in the final moments of descent, SpaceX flipped the rocket and returned it to a vertical orientation, firing the Raptor engines to slow itself down for the landing.
SpaceX aimed to launch the prototype as high as 10 kilometers, or about 32,800 feet altitude. There were no passengers onboard the rocket, as it is a development vehicle and flies autonomously.
Like SN8 and SN9, the goal of the Starship SN10 flight was not necessarily to reach the maximum altitude, but rather to test several key parts of the Starship SN10 system. SpaceX fired all three engines for liftoff and then shut them down one at a time in sequence as the rocket neared the top of the flight’s intended altitude.
SpaceX is developing Starship SN10 to get people and payloads to the moon, Mars and other distant destinations, and to fly any other missions the company requires. Indeed, SpaceX plans to eventually phase out its other flight hardware — the Falcon 9 and Falcon Heavy rockets and Dragon cargo and crew capsules — and let Starship shoulder the entire load, company founder and CEO Elon Musk has said.
Musk believes that Starship’s combination of rapid reusability and power, the system will be able to loft more than 110 tons (100 metric tons) to low Earth orbit, according to its SpaceX specifications page — is the breakthrough that will make ambitious feats such as Mars settlement economically feasible.
Musk remains “highly confident” that Starship SN10 “will be safe enough for human transport by 2023″ – an ambitious goal given the company began the rocket’s development and testing in earnest in early 2019. He also revealed that other methods of recovering Starship safely had also been considered, beyond using rockets and complex artificial intelligence systems to self-land the ship.
The tests take place in a nearly deserted area leased by SpaceX in South Texas near the border with Mexico and Gulf of Mexico – the area is vast and empty enough that an accident or explosion would not likely cause damage or fatalities.
It was the first time a Starship SN10 prototype had landed after a major flight test, however the third time one of these tests ended in the Mars-bound craft exploding. A combination of low thrust propellent, a heavy impact and crushed landing legs resulted in Starship SN10’s fiery demise, the technology billionaire tweeted on Tuesday.
SpaceX finally appeared to make a soft landing of the latest prototype for its next-generation Starship SN10 rocket. But several minutes later, Starship SN10, as the third prototype to make a high-altitude test flight was known, made an unplanned second flight after it exploded on the landing pad. A close look at the landing of Starship SN10 reveals it came in a little hot and fast. It even appeared to bounce slightly upon touching down.
But that wasn’t the end of the story. Some flames were visible near Starship SN10’s base shortly after landing, and that was a sign of things to come: the vehicle exploded on the landing pad at about 6:30 p.m. EST (2330 GMT), rising up and crashing down again in a huge fireball.
This time the destruction was delayed, rather than a crash landing. The prototype appeared to be steadying itself as planned, before bursting into flames around eight minutes after arriving on the landing pad.
Musk went on to explain that the helium ingestion was probably the result of a pressurization system that had been added to the methane header tank to fix a problem that occurred in a previous starship prototype, Starship SN10.
“If autogenous pressurization had been used, CH4 bubbles would most likely have reverted to liquid,” he said. “Helium in header was used to prevent ullage collapse from slosh, which happened in prior flight. My fault for approving. Sounded good at the time.”
The test, however, was still hailed as a success as Starship SN10 landed and remained in one piece significantly longer than two earlier prototypes that exploded on impact.
Starship SN10 is one of two “Manhattan Projects” that SpaceX is simultaneously developing, with the other being its Starlink satellite internet program. Musk has previously estimated that it will cost about $5 billion to fully develop Starship SN10, although SpaceX has not disclosed how much it has spent on the program to date.
SpaceX already has an operational Starship SN10 flight targeted to launch that year — the “dearMoon” mission booked by Japanese billionaire Yusaku Maezawa. Maezawa is looking for crewmembers to join him on that six-day journey around the moon.