Elon Musk’s SpaceX Starship: breaking-down the breakdown

This article originally appeared in the June'23 magazine issue of Electronic Specifier Design – see ES's Magazine Archives for more featured publications.

Elon Musk’s SpaceX Starship, a 50m tall spacecraft designed for crew and cargo missions that sits atop the massive 70m tall Super Heavy Rocket, was launched on 20th April 2023 from the SpaceX spaceport, Starbase, in Boca Chica, Texas. The giant rocket successfully launched and reached maximum dynamic pressure conditions (max q) before eventually terminating after a failure to complete first stage separation.

The launch was an overwhelming success for its first flight, despite the initial launch being postponed due to technical faults, the rocket’s eventual termination, and Musk’s early concerns, in which he stated: “It’s a very risky flight. It’s the first launch of a very complicated, gigantic rocket… there’s a million ways this rocket could fail.” But overall, Musk was optimistic about the launch, deeming it an overall success: “Obviously not a complete success, but still nonetheless successful.” He added that the goal of the test was “to learn a lot, and we learned a lot.” Musk continued by teasing more test flights in 2023.

A timeline of the launch

As the clock ticked over to 8:33am CDT (14:33pm BST), all 33 of the raptor engines fired up, and at T+6 seconds, Starship had lift-off. The launch quickly deviated from its intended path, evident as the rocket began gaining altitude. Credit should be given to SpaceX, who displayed informative graphics on its webcast throughout the launch, highlighting vehicle speed, altitude, propellant levels, and engine status – showing in real-time what was going wrong. At T+15 seconds, the graphics revealed that three of the Raptor engines were not operational as expected – two adjacent engines in the outer ring and one central engine capable of gimballing for attitude control. These three engines were never engaged as the rocket fired up, deemed too risky to ignite in the final stages.

As the flight progressed, additional Raptor engines shut down, resulting in at least six engines being out of service at various stages. There was also debris observed near the booster’s base around T+30 seconds, accompanied by some visible flaring in the plume. Despite these factors, the rocket continued to accelerate and make its ascent, powered by the remaining Raptor engines and the increasingly enthusiastic cheers of the SpaceX employees at the company’s headquarters in Hawthorne, California, overpowering the webcast commentary.

The vehicle pushed through max q and continued its flight still. However, around two and a half minutes into the flight, the vehicle began a slow tumble. Initially, the webcast commentators speculated that this may have been a part of the stage separation process, as per SpaceX’s pre-launch timeline, which indicated Starships’s separation from Super Heavy at T+2:52.

Despite the anticipation, expected stage separation did not occur, and the slow tumble persisted, albeit with the vehicle remaining structurally sound. As the cheers at Hawthorne subsided, and the time reached T+3:45, SpaceX’s John Insprucker acknowledged on the webcast: “We should have had separation by now. Obviously, this does not appear to be a normal situation.”

Shortly thereafter, just before the T+4-minute mark, the vehicle erupted into a white cloud with a faint hint of a fireball. SpaceX later confirmed that the flight termination systems on both Super

Heavy and Starship had been triggered. The inaugural integrated flight of Starship and Super Heavy fell significantly short of the planned splashdown near Hawaii. However, cheers still resurged around Hawthorne. Siva Bharadvaj, another host of the SpaceX webcast, explained: “Everyone here is absolutely pumped to clear the pad and make it this far into the test flight.”

Concerns over the pad

Whilst the spectacle of the launch was in the skies above, the picture on the ground wasn’t so pretty. Upon their ignition, the Raptor engines generated substantial clouds of dust and sand which engulfed the launch pad entirely. In the process, it is likely that the engines also picked up fragments from the pad itself. SpaceX released a video which shows material falling into the waters of the Gulf of Mexico as the rocket ascended, likely consisting of sizable chunks of pad material, rocks, or other debris dislodged by the rocket’s intense exhaust plume. Once the dust had settled, a large crater was seen in the place of the rocket, dug out from the massive forces generated by the thrust of the rocket.

Photographers, who had set up their cameras to capture the monumental launch and were able to retrieve what they could two days later, noted extensive damage to the launch mount and the nearby water tank farm. Unlike traditional launch complexes, there was no flame trench or similar system in place to redirect the massive plumes generated by the rocket’s exhaust during lift-off.

Figure 1 - Starship on the Starbase launchpad, Boca Chica, Texas. Credit: SpaceX Flickr

Musk was seemingly rather nonchalant about the damage to the pad despite previously mentioning that: “[His] top hope is please, may fate smile upon us and we clear the launch pad before anything goes wrong,” continuing to say how “it would probably take us several months to rebuild the launch pad.” In a tweet the day after the launch, he stated: “Three months ago, we started building a massive water-cooled, steel plate to go under the launch mount.” Unfortunately, it was not completed in time, but SpaceX continued with the launch regardless, anticipating that the concrete would erode instead of fracturing.

Other reservations

In addition, SpaceX might have to confront the environmental consequences arising from the launch. Local residents of Port Isabel, situated near South Padre Island, witnessed the descent of fine-grained debris, likely sand, onto their town, carried in by the rocket’s exhaust plume. There were also isolated incidents reported surrounding broken windows in the vicinity. The Federal Aviation Administration (FAA), responsible for granting SpaceX its launch license, will investigate these matters as part of its oversight during the investigation into the launch incident.

What’s next?

Looking ahead, SpaceX has no plans to halt progress, charging headfirst into its next launch utilising the new findings of the first. The company has already filed for a permit with the Federal Communications Commission (FCC) requesting authorisation for a second test flight as soon as 15th June 2023, but anytime until 15th December 2023 in the longer run.

The planned mission would once again lift off from Starbase in Boca Chica, Texas, and would include the Super Heavy Booster returning to the Gulf of Mexico after separation and achieving touchdown at approximately T+8:25. The Starship meanwhile will enter orbit before finally landing in the Pacific Ocean northwest of the Hawaiian island of Kauai, estimated to be around 90 minutes following its launch.

However, the launch is contingent upon receiving regulatory approval from the FAA, who are (as previously mentioned) conducting ongoing environmental assessments of the Starship’s launch operations. Although the FAA has not provided a specific timeline for the completion of the assessment, the public who could be affected by the launch will have an opportunity to provide feedback on the draft assessment. Based on this assessment, the FAA will determine whether a more comprehensive environmental impact statement is necessary.