SpaceX launches Super Heavy-Starship rocket on third test flight

The huge SpaceX Super heavy spaceship The rocket, the most powerful ever built, lifted off on its third test flight Thursday morning, successfully propelling the unmanned upper stage into space on a suborbital jump toward a fiery reentry over the Indian Ocean.

Dramatic live video from a camera mounted on one of the Starship’s fins showed the red glow of reentry heating as the spacecraft fell back into the lower atmosphere, becoming increasingly intense until it was enveloped in a bright ball of fire. The insulating tiles in the belly of the Starship experienced temperatures exceeding 2,500 degrees.

Telemetry stopped flowing at an altitude of about 40 miles, indicating that Starship disintegrated before it could make a rocket-powered descent to a destructive splashdown in the Indian Ocean. But getting from launch to space and then deep enough in the atmosphere to experience maximum warming was a major achievement.

“Today has been a phenomenal day,” said one SpaceX commentator.

The test flight began at 9:25 a.m. EDT when the giant rocket’s 33 Raptor engines, swallowing 40,000 pounds of liquid oxygen and methane propellants per second, roared to life with a ground-shaking roar.

A moment later, the 394-foot-tall rocket began to ascend skyward, shooting through billowing clouds of dust and vapor generated by the fiery exhaust of the propellant that vaporized torrents of water that sprayed upward at the base of the rocket. platform to alleviate the impact of engine ignition.

Gently accelerating, burning propellants and losing weight, the Super Heavy-Starship arced eastward over the Gulf of Mexico, putting on a spectacular spectacle for thousands of area residents, tourists and a crowd of journalists watching from the launch site. and the near south. Padre Island, a few miles north.

The 33 Raptors appeared to fire normally, propelling the rocket beyond the region of maximum aerodynamic stress as it accelerated to the speed of sound and exited the dense lower atmosphere.

Two minutes and 42 seconds after liftoff, the Raptors began shutting down as planned, followed seconds later by the ignition of all six Starship upper stage engines while the booster was still connected, a recent modification known as “startup.” hot scene”. A moment later, the Super Heavy and Starship stages separated cleanly.

As Starship continued its ascent into space, the booster rotated and began returning to shore for its descent to landing. Most of the fall back to Earth went smoothly and her engines were fired as necessary to slow her down.

But as it approached the Gulf and passed through low cloud covers, the Super Heavy began to oscillate in wide arcs as it struggled to maintain its orientation. At that point, the spacecraft’s camera views were lost and the booster went into a “hard splashdown” without a planned engine ignition, known as a landing burn.

Meanwhile, the Starship appeared to make a flawless ascent into space. Her Raptors shut down eight and a half minutes after she lifted off and the spacecraft beamed back spectacular views of space and the edge of the Earth as flight controllers carried out a series of tests. Re-entry began about 40 minutes later.

Problems with previous test flights

Two previous test flights ended in spectacular self-destruct conflagrations. the firstlast April, after multiple shutdowns of Super Heavy engines and a malfunction of the stage separation and the secondin November, just before Starship had begun a planned orbit around the planet for a splashdown in the Pacific Ocean north of Hawaii.

SpaceX engineers modified multiple systems in the wake of the failures, including work to strengthen the rocket’s self-destruct system, improve engine performance and protect the pad with a high-powered water deluge system that also dampens acoustic impact. of the engine ignition. .

The company also implemented the “hot staging” technique in which the Starship’s six Raptor engines are fired while the stage is still attached to the Super Heavy booster. Hot staging, used for decades by Russian Soyuz rockets, helps ensure a more efficient stage separation sequence.

“Starship’s second flight test achieved a number of important milestones and provided invaluable data to continue to rapidly develop Starship,” SpaceX said on its website. “This rapid iterative development approach has been the foundation for all of SpaceX’s major innovative advancements.”

For its third test flight, the primary objectives were more or less the same: propel the Starship into space for a suborbital test flight and high-speed re-entry and perform controlled landings by both stages, the Super Heavy in the Gulf. of Mexico and the Starship in the Indian Ocean.

SpaceX pioneered technology that allows the company to recover and reuse smaller Falcon 9 boosters. But no spacecraft has ever attempted to descend through the atmosphere from space, subjecting the insulating plates of its belly to temperatures exceeding 2,500 degrees.

While both stages are designed to be completely reusable, there were no recovery plans for the third test flight. The flight plan called for both stages to attempt rocket-powered descents mimicking actual landing procedures and both were expected to break up and sink upon impact into the ocean. As it turned out, none of the stages went that far. But it was close.

In any case, during the Starship’s progress toward the entrance, flight controllers tested a payload door that will be used on future flights to launch Starlink satellites.

Most importantly for NASA, the rocket successfully transferred cryogenic propellants from one tank to another in the weightless environment of space and performed the first restart of a Raptor engine outside the atmosphere.

The propellant transfer test and the Raptor restart are critical milestones for NASA, which is paying billions to SpaceX to build a Starship variant to serve as the Human Landing System, or HLS, for the NASA’s Artemis lunar program. agency.

The HLS will require automated refueling in Earth orbit by multiple Super Heavy-Starship tankers before restarting its engines to head to the moon and await the arrival of astronauts who will use the spacecraft to transport them to and from the moon. surface.

Up to 10 refueling flights will be required for an HLS flight to the Moon.

The largest rocket ever built

While clearly a challenge, the fully reusable Super Heavy-Starship, known collectively simply as “Starship”, is a potential game-changer, a potentially revolutionary step aimed at increasing payload weight in orbit while reducing enormously the cost.

It is the largest rocket ever built, standing 39 stories tall, measuring 29.5 feet wide and generating more than 16 million pounds of thrust with its SpaceX-designed Raptor engines, twice the power of the Space Launch System moon rocket. NASA and the agency’s legendary Saturn 5. .

The Super Heavy first stage alone is 23 stories tall, while the Starship upper stage, designed to carry cargo, passengers or both, rises another 164 feet and is equipped with six Raptor engines of its own.

The Super Heavy is designed to fly back to its launch pad, either at Boca Chica or the Kennedy Space Center in Florida, after boosting Starship’s upper stage out of the lower atmosphere and then descending to land, captured by two huge robotic arms on the launch gantry.

The spacecraft are designed to fly themselves to land anywhere landing pads are available, as well as on the Moon and, eventually, Mars.

SpaceX launched the Super Heavy-Starship on its maiden flight on April 20, but the rocket suffered multiple engine failures or shutdowns. The rest continued firing after the planned stop time and the first and second stages failed to separate normally. The self-destruct system activated, but it took longer than expected to activate.

Visibly falling, the rocket exploded four minutes after takeoff. The maximum altitude was 24 miles.

On its second test flight on November 18, the Super Heavy booster operated normally, the hot preparation procedure worked as planned and the Starship upper stage separated normally to continue the ascent into space with the power of its six Raptor engines.

Meanwhile, the Super Heavy turned as expected and began flying back toward the Texas coast to splash down. But moments after spinning, the rocket exploded in a shower of debris. The Starship stage flew into space as planned, but just before or during engine shutdown, it also exploded.

Getting the Super Heavy-Starship to fly regularly is essential to NASA’s Artemis lunar program. NASA awarded SpaceX a $2.9 billion contract in 2021 to develop a variant of the Starship upper stage to transport astronauts from lunar orbit to the surface and back. Artemis crews will travel to and from the moon using Orion capsules built by Lockheed Martin.

NASA’s contract requires an unpiloted lunar landing test flight before astronauts make an actual landing attempt. Those responsible for Artemis point to the end of 2026 for the first lunar landing with astronauts on board.

But that will depend on SpaceX launching enough Super Heavy-Starship flights to demonstrate reliability. While SpaceX’s philosophy is to fly frequently, learn from mistakes and fly again, NASA will need a long series of successful flights before the agency considers it safe to take astronauts on board.