Rocket Failures: Starship's Explosion

Ethan Wong

April 21, 2023, updated for November 18th flight

Starship was a highly anticipated rocket that launched on April 20th, 2023, and left everyone in shock as it exploded. Despite having 33 methane-powered raptor engines–giving the rocket a substantial amount more thrust than the Saturn V–it never reached space and was seen as both a huge let-down to SpaceX and the public, but also room for multiple improvements. 

Because Starship is intended to travel to Mars and back to Earth in the future, Elon Musk and SpaceX have worked on launching their rocket without the need for flame diverters, as they wouldn’t be able to create a launch pad for the rocket on Mars like they would from Earth. Consequently, many observers and SpaceX engineers noted that the removal of a flame diverter caused a lot of concrete debris to be thrown up at the rocket during the launch, which could explain why 3 of the raptor engines failed during the launch. 

One of the main objectives for the launch was to test Starship’s stage separation while traveling in the air. However, the Starship Super Heavy Booster (second stage) failed to disconnect from the first stage and the rocket started to spin around after reaching its apex height, signaling a loss of control. Because all of the propellant in the second stage of the rocket was still present due to the failed stage separation, the rocket had unequal weight in the upper half while falling horizontally (concentrated on one side essentially), causing the entire structure to be compromised and create an explosion. 

On November 18th, 2023, Starship took off on its second flight from Texas with an intended day trip around the globe, landing near the islands of Hawaii in the Pacific Ocean. Although the flight failed (with explosions again), this second attempt has demonstrated large improvements from its maiden flight, such as the consistency of its 33 Raptor engines on its first stage, the safety of the launch pad, and the absence of flying debris, as well as a successful stage separation which didn’t even happen the first time. 

Let’s work this backward. Before the launch, SpaceX installed a water deluge system for Starship’s launch to prevent concrete debris from damaging the Raptor engines on takeoff, which was a fatal blow to its first flight. The water deluge system has two key components: the base, and water (of course). A steel plate was added to the base of the launchpad so concrete debris wouldn’t form, yet this still posed a threat, as the engines could tear through the steel and cause steel debris to attack itself. Because of this, there are several holes in the steel plate where water will shoot out during takeoff. This pressurized water will protect the steel base and make it reusable for every launch, while also being vaporized by the flames of the rocket. While there is still an absence of a flame diverter, the system worked brilliantly during takeoff and none of the engines were damaged.

On its maiden flight, Starship had already lost more than 5 of its Raptor engines, one of the main causes of its demise. However, the new launch pad enabled the rocket to escape the ground with 33 healthy engines that all worked consistently until stage separation. 

At T-2:48 minutes into the launch, all but 3 Raptor engines were cut off from the first stage and the second stage engines ignited. The booster successfully disconnected from the Starship upper stage; while the upper stage continued to ascend the atmosphere without any visible problems, the super heavy booster experienced its first problem having to deal with the engines, causing it to explode after 3 minutes into the flight (the lower stage did flip successfully, however). As pointed out by Youtuber Scott Manley, around 8 minutes into the flight, the flight profile of SpaceX’s stream suddenly showed a drastic decrease in liquid oxygen (LOX) levels in its tank compared to the methane (CH4) being burned. At this time, all the Raptor engines went out and the stage exploded. Manley mentions that a loss of LOX could have resulted from a leak but was probably a factor in the explosion. 

Ultimately, this second launch of Starship was a huge redemption for its previous attempt and has showcased that SpaceX is getting closer and closer to making it safe for humans. However, there still lie many challenges that Starship has to face to be eligible to safely escort humans to Mars, even if it performs well on Earth.