Dec 11, 2020

So, it Turns Out SpaceX is Pretty Good At Rocketing

As the Sun sank toward the South Texas horizon, a fantastical-looking spaceship rose into the reddening sky.

It was, in a word, epic.

Powered by three Raptor rocket engines, SpaceX's 50-meter-tall Starship vehicle climbed out over the Gulf of Mexico. After a couple of minutes, one by one, the Raptor engines blinked off by design. It was not immediately clear how high Starship reached, but the craft appeared to come close to the 12.5km ceiling on the flight test.

At this apogee, Starship faced what may have been its most critical test—using reaction control thrusters to perform was has become known as a "belly flop" so the vehicle can return to Earth at an angle of attack of about 70 degrees. This maneuver is critical for a Starship returning from orbit, both to bleed off velocity as well as ensure its reusability without a massive heat shield. Starship nailed this move, smooth as soft butter.

As the shiny spaceship neared the ground, it then successfully reoriented itself to a vertical position to prepare for a landing. And it almost succeeded. Alas, pressure in the Starship header tanks, located in the upper part of the vehicle, was not high enough. Effectively, this deprived the Raptor engines of the thrust they needed to slow down enough. So Starship crashed into the landing pad and created a fiery spectacle.

See the fate of SN8.

Nothing as mundane as header-tank pressure could deter the enthusiasm of SpaceX founder and chief engineer Elon Musk, who shared this cause of the crash on Twitter. "We got all the data we needed!" he wrote. "Congrats SpaceX team hell yeah!!" There will undoubtedly be partying in South Texas and Hawthorne, California, tonight.

Musk's enthusiasm, and that of his team of engineers and technicians, should not be dampened. This was one heck of a test-flight that addressed a number of unknowns about Starship, which is the upper stage of SpaceX's new launch system and may one day land humans on the Moon, Mars, and beyond.

The methane-fueled Raptor engines had never been tested like this in flight, and they appeared to perform exceptionally well during the rocket's ascent. The vehicle was also able to switch seamlessly from its main fuel tanks near the base of the vehicle to the smaller header fuel tanks. Perhaps most impressively, the unprecedented belly flop maneuver and demonstration of Starship's aerodynamics bode extremely well for the company's plans to reuse the vehicle.

And SpaceX did it all out in the open for the world to see. Over the last year, Musk has built a factory beneath tents near Boca Chica Beach in South Texas. All of the tests have been done in plain view. Along the way, SpaceX has failed and succeeded but, ultimately, made rapid progress. Only 15 months have passed since SpaceX was scrambling to complete an initial prototype called "Mark 1." The vehicle that ended its brief career in flames on Wednesday was "Serial Number 8," or SN8.

Already, SN9 is essentially complete. In the coming days, Musk and his engineers will assess the data from Wednesday's flight and clean up the landing site—it does not appear as though significant damage was done to the extensive farm of fuel tanks and ground systems near the launch and landing pad. Very soon, Musk et al. will roll SN9 to the second launch site in South Texas and run this experiment again. This may happen within weeks. Beyond SN9, SpaceX has a half-dozen more Starship prototypes in the works. They are going to fly, and fly a lot, in the coming months.

The timing of all this is good for SpaceX. This month, SpaceX—along with teams led by Blue Origin and Dynetics—is submitting proposals to develop a Human Landing System for NASA's Artemis Program to land humans on the Moon. The space agency will select one, or at most two, companies to proceed with a development contract worth billions of dollars.

On Wednesday, Blue Origin released a video that highlighted the full-scale mockup it has delivered to Johnson Space Center of its lander. Meanwhile, a few hundred kilometers south of Houston, SpaceX launched its lander—a real rocket, real engines, and a real flight.

It was something to behold.

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