Earlier this month, SpaceX launched its Starship megarocket for the fifth time. It was a momentous occasion, one made even more remarkable when the rocket’s reusable booster returned to the liftoff site and was caught by the mechanical arms of the launch tower. Little did anyone know, though, that this incredible achievement was a mere second away from becoming a disaster.
A successful recapture: How Starship was overshadowed by its booster on Flight 5
To date, Starship is the largest and most powerful rocket in existence. Although it stands at a height of 165 feet, the behemothic spacecraft is somewhat overshadowed by the presence of its first-stage booster, known as “Super Heavy,” which itself reaches a height of 230 feet. Powered by 33 Raptor engines, Super Heavy is designed to elevate Starship to greater altitudes for its entry into space.
On Sunday, October 13, SpaceX launched its fifth Starship test flight from the company’s Starbase site in Boca Chica, Texas. Approximately seven minutes after liftoff, Super Heavy separated itself from the spacecraft, turned around, and returned in the direction of the launchpad.
Spectators watched in awe as Super Heavy’s landing burn activated, decelerating it to a steady hover as it descended. The launch tower’s massive “chopstick” arms then caught and secured the booster in place, causing even more of a joyous uproar from the crowd.
It was a miracle that SpaceX narrowly avoided a huge catastrophe
Nearly two weeks after the historic feat, SpaceX founder and CEO Elon Musk revealed that the catch landing was not as smooth as it appeared.
Taking to X on Friday, October 25, Musk shared a three-minute clip from his livestream session of “Diablo IV.” Of interest, however, is the audio, in which he’s heard having a candid conversation with three unidentified SpaceX engineers about the issues they encountered while catching Super Booster during Flight 5.
“We had a misconfigured spin gas abort that didn’t have quite the right ramp-up time for bringing up spin pressure,” explained one engineer. “And we were one second away from that tripping and telling the rocket to abort and try to crash into the ground next to the tower instead of [landing at] the tower—like, erroneously tell a healthy rocket to not try that catch.”
A second engineer remarked that there were talks of delaying the test flight due to the amount of “aborts and commit criteria” that would have resulted in the booster failing even if all systems were functioning normally.
Crisis averted despite major structural failure of Super Heavy
Frighteningly, an abort scenario was almost realized when the chine, a cover that protects the vertical structure on Super Heavy, came off in the midst of the booster’s descent. This could have easily jeopardized the tower catch as well.
“This cover that ripped off was right on top of a bunch of the single-point failure valves that must work during the landing burn,” another engineer revealed. “Thankfully, none of those or the harnessing got damaged, but we ripped this chine cover off over some really critical equipment right as the landing burn was starting.”
The same engineer added that they “have a plan to address” this issue in preparation for Starship’s upcoming sixth test flight.
For all intents and purposes, the team at SpaceX is fully committed to improving Super Heavy’s capabilities and preventing catastrophes on the journey towards deep-space exploration. Granted, thorough checks and rigorous testing will be needed to ensure the functionality of both the booster and Starship. Nevertheless, the return and successful catch of Super Heavy represents a significant step forward in space technology.